[ttml11] Regenerate ED.
authorGlenn Adams <glenn@skynav.com>
Tue, 09 Jul 2013 14:40:16 -0600
changeset 429 f2ae6b048445
parent 428 9e3f6c1d5cd9
child 430 3912ba9d9c4a
[ttml11] Regenerate ED.
ttml11/spec/ttml11.html
--- a/ttml11/spec/ttml11.html	Tue Jul 09 14:39:28 2013 -0600
+++ b/ttml11/spec/ttml11.html	Tue Jul 09 14:40:16 2013 -0600
@@ -1,7 +1,6 @@
-<?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE html
-  PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
-<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-us" lang="en-us"><head><meta http-equiv="Content-Type" content="application/xhtml+xml; charset=utf-8"/><title>Timed Text Markup Language (TTML) 1.1 -- (Editors' copy)</title><style type="text/css">
+  PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<html lang="en-us"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"><title>Timed Text Markup Language (TTML) 1.1 -- (Editor's copy)</title><style type="text/css">
 code           { font-family: monospace; }
 
 div.constraint,
@@ -50,10 +49,26 @@
 table.syntax th { border: 0px solid black; text-align: left }
 table.syntax td { border: 0px solid black }
 table.syntax div { background-color: #ffffc8 }
+table.semantics { border: 0px solid black; width: 85%; border-collapse: collapse }
+table.semantics caption { font-weight: bold; text-align: left; padding-bottom: 0.5em }
+table.semantics th { border: 0px solid black; text-align: left }
+table.semantics td {
+  border-left: 0px solid black;
+  border-right: 0px solid black;
+  border-top: 4px double #d3d3d3;
+  border-bottom: 4px double #d3d3d3;
+  background-color: #ccffcc
+}
+table.semantics code.formulae {
+  padding: 1em;
+  border: 1px dashed #005a9c;
+  line-height: 1.1em;
+  background-color: #fdfdfd;
+}
 table.example { border: 0px solid black; width: 85%; border-collapse: collapse }
 table.example caption { font-weight: bold; text-align: left; padding-bottom: 0.5em }
 table.example th { border: 0px solid black; text-align: left }
-table.example td { border: 0px solid black }
+table.example td { border: 0px solid black;  }
 table.example div { background-color: #c8ffff }
 table.example-images { text-align: center; border: 0px solid black; width: 85%; border-collapse: collapse }
 table.example-images caption { font-weight: bold; text-align: center; padding-bottom: 0.5em }
@@ -65,19 +80,15 @@
 .strong { font-weight: bold }
 .reqattr { font-weight: bold }
 .optattr { font-style: italic }
-
-.diff-add  { color: red; background-color: #99FF99; }
-.diff-del  { color: red; text-decoration: line-through; background-color: #99FF99; }
-.diff-chg  { background-color: #99FF99; }
-q.diff-off  {}
-</style><link rel="stylesheet" type="text/css" href="http://www.w3.org/StyleSheets/TR/W3C-ED.css"/></head><body>Last Modified: $Date$<div id="revisions"/><div class="head">
-<h1><a name="title" id="title"/>Timed Text Markup Language (TTML) 1.1</h1>
-<h2><a name="w3c-doctype" id="w3c-doctype"/>Editors' copy $Date$ @@ @@@@ @@@@</h2><dl><dt>This version:</dt><dd>
+</style><link rel="stylesheet" type="text/css" href="http://www.w3.org/StyleSheets/TR/W3C-ED.css"></head><body>Last Modified: $Date: 2013/07/09 20:39:28 $<div id="revisions"></div><div class="head">
+<h1><a id="title"></a>Timed Text Markup Language (TTML) 1.1</h1>
+<h2><a id="w3c-doctype"></a>Editors' copy $Date: 2013/07/09 20:39:28 $ @@ @@@@ @@@@</h2><dl><dt>This version:</dt><dd>
 <a href="ttml11.html">ttml11.html</a>
 </dd><dt>Latest version:</dt><dd><a href="http://dvcs.w3.org/hg/ttml/raw-file/tip/ttml11/spec/ttml11.html?content-type=text/html;charset=utf-8">http://dvcs.w3.org/hg/ttml/raw-file/tip/ttml11/spec/ttml11.html?content-type=text/html;charset=utf-8</a></dd><dt>Previous version:</dt><dd>
 <a href="http://www.w3.org/TR/2010/REC-ttaf1-dfxp-20101118/">http://www.w3.org/TR/2010/REC-ttaf1-dfxp-20101118/</a>
-</dd><dt>Editor:</dt><dd>Glenn Adams, Cox Communications, Inc.</dd><dt>Contributing Authors:</dt><dd>Mike Dolan, Invited Expert</dd><dd>Geoff Freed, WGBH National Center for Accessible Media</dd><dd>Sean Hayes, Microsoft</dd><dd>Erik Hodge, RealNetworks</dd><dd>David Kirby, British Broadcasting Corporation (BBC)</dd><dd>Thierry Michel, W3C</dd><dd>Dave Singer, Apple Computer</dd></dl><p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © @@@@ <a href="http://www.w3.org/"><acronym title="World Wide Web Consortium">W3C</acronym></a><sup>®</sup> (<a href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute of Technology">MIT</acronym></a>, <a href="http://www.ercim.eu/"><acronym title="European Research Consortium for Informatics and Mathematics">ERCIM</acronym></a>, <a href="http://www.keio.ac.jp/">Keio</a>, <a href="http://ev.buaa.edu.cn/">Beihang</a>), All Rights Reserved. W3C <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document use</a> rules apply.</p></div><hr/><div>
-<h2><a name="abstract" id="abstract"/>Abstract</h2><p>This document specifies the Timed Text Markup Language (TTML) in terms of a
+</dd><dt>Editor:</dt><dd>Glenn Adams, Cox Communications, Inc.</dd><dt>Contributing Authors:</dt><dd>Mike Dolan, Invited Expert</dd><dd>Geoff Freed, WGBH National Center for Accessible Media</dd><dd>Sean Hayes, Microsoft</dd><dd>Erik Hodge, RealNetworks</dd><dd>David Kirby, British Broadcasting Corporation (BBC)</dd><dd>Thierry Michel, W3C</dd><dd>Dave Singer, Apple Computer</dd></dl><p>Please refer to the <a href="https://dvcs.w3.org/hg/ttml/raw-file/default/ttml10/spec/ttml-issues.html">errata</a> for this document, which may
+      include normative corrections.</p><p>See also <a href="http://www.w3.org/2003/03/Translations/byTechnology?technology=ttml11"><strong>translations</strong></a>.</p><p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a>&nbsp;©&nbsp;@@@@&nbsp;<a href="http://www.w3.org/"><acronym title="World Wide Web Consortium">W3C</acronym></a><sup>®</sup> (<a href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute of Technology">MIT</acronym></a>, <a href="http://www.ercim.eu/"><acronym title="European Research Consortium for Informatics and Mathematics">ERCIM</acronym></a>, <a href="http://www.keio.ac.jp/">Keio</a>, <a href="http://ev.buaa.edu.cn/">Beihang</a>), All Rights Reserved. W3C <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document use</a> rules apply.</p></div><hr><div>
+<h2><a id="abstract"></a>Abstract</h2><p>This document specifies the Timed Text Markup Language (TTML) in terms of a
 vocabulary and semantics thereof.</p><p>The Timed Text Markup Language is a content type that represents
 timed text media for the purpose of interchange among authoring
 systems. Timed text is textual information that is intrinsically or
@@ -85,373 +96,352 @@
 for the purpose of transcoding or exchanging timed text information
 among legacy distribution content formats presently in use for
 subtitling and captioning functions.</p><p>In addition to being used for interchange among legacy distribution content
-formats, TTML content may be used directly as a distribution format,
-for example, providing a standard content format to reference from a <code>&lt;text&gt;</code> or 
-<code>&lt;textstream&gt;</code> media object element in a <a href="#smil21">[SMIL 2.1]</a> document.</p></div><div><h2><a name="status" id="status"/>Status of this Document</h2><p><strong>This document is an editor's copy that has no official standing.</strong></p><p/></div><div class="toc">
-<h2><a name="contents" id="contents"/>Table of Contents</h2><p class="toc">1 <a href="#intro">Introduction</a><br/>
-    1.1 <a href="#model">System Model</a><br/>
-    1.2 <a href="#example">Document Example</a><br/>
-2 <a href="#definitions">Definitions</a><br/>
-    2.1 <a href="#acronyms">Acronyms</a><br/>
-    2.2 <a href="#terms">Terminology</a><br/>
-    2.3 <a href="#conventions">Documentation Conventions</a><br/>
-3 <a href="#conformance">Conformance</a><br/>
-    3.1 <a href="#conformance-content">Content Conformance</a><br/>
-    3.2 <a href="#conformance-processor">Processor Conformance</a><br/>
-        3.2.1 <a href="#conformance-generic-processor">Generic Processor Conformance</a><br/>
-        3.2.2 <a href="#conformance-transformation-processor">Transformation Processor Conformance</a><br/>
-        3.2.3 <a href="#conformance-presentation-processor">Presentation Processor Conformance</a><br/>
-    3.3 <a href="#claims">Claims</a><br/>
-4 <a href="#doctypes">Document Types</a><br/>
-    4.1 <a href="#dfxp-content-doctype">DFXP Content</a><br/>
-5 <a href="#vocabulary">Vocabulary</a><br/>
-    5.1 <a href="#vocabulary-namespaces">Namespaces</a><br/>
-    5.2 <a href="#vocabulary-profiles">Profiles</a><br/>
-    5.3 <a href="#vocabulary-overview">Catalog</a><br/>
-        5.3.1 <a href="#core-vocabulary-overview">Core Catalog</a><br/>
-        5.3.2 <a href="#extension-vocabulary-overview">Extension Catalog</a><br/>
-6 <a href="#parameters">Parameters</a><br/>
-    6.1 <a href="#parameter-element-vocabulary">Parameter Element Vocabulary</a><br/>
-        6.1.1 <a href="#parameter-vocabulary-profile">ttp:profile</a><br/>
-        6.1.2 <a href="#parameter-vocabulary-features">ttp:features</a><br/>
-        6.1.3 <a href="#parameter-vocabulary-feature">ttp:feature</a><br/>
-        6.1.4 <a href="#parameter-vocabulary-extensions">ttp:extensions</a><br/>
-        6.1.5 <a href="#parameter-vocabulary-extension">ttp:extension</a><br/>
-    6.2 <a href="#parameter-attribute-vocabulary">Parameter Attribute Vocabulary</a><br/>
-        6.2.1 <a href="#parameter-attribute-cellResolution">ttp:cellResolution</a><br/>
-        6.2.2 <a href="#parameter-attribute-clockMode">ttp:clockMode</a><br/>
-        6.2.3 <a href="#parameter-attribute-dropMode">ttp:dropMode</a><br/>
-        6.2.4 <a href="#parameter-attribute-frameRate">ttp:frameRate</a><br/>
-        6.2.5 <a href="#parameter-attribute-frameRateMultiplier">ttp:frameRateMultiplier</a><br/>
-        6.2.6 <a href="#parameter-attribute-markerMode">ttp:markerMode</a><br/>
-        6.2.7 <a href="#parameter-attribute-pixelAspectRatio">ttp:pixelAspectRatio</a><br/>
-        6.2.8 <a href="#parameter-attribute-profile">ttp:profile</a><br/>
-        6.2.9 <a href="#parameter-attribute-subFrameRate">ttp:subFrameRate</a><br/>
-        6.2.10 <a href="#parameter-attribute-tickRate">ttp:tickRate</a><br/>
-        6.2.11 <a href="#parameter-attribute-timeBase">ttp:timeBase</a><br/>
-7 <a href="#content">Content</a><br/>
-    7.1 <a href="#content-element-vocabulary">Content Element Vocabulary</a><br/>
-        7.1.1 <a href="#document-structure-vocabulary-tt">tt</a><br/>
-        7.1.2 <a href="#document-structure-vocabulary-head">head</a><br/>
-        7.1.3 <a href="#document-structure-vocabulary-body">body</a><br/>
-        7.1.4 <a href="#content-vocabulary-div">div</a><br/>
-        7.1.5 <a href="#content-vocabulary-p">p</a><br/>
-        7.1.6 <a href="#content-vocabulary-span">span</a><br/>
-        7.1.7 <a href="#content-vocabulary-br">br</a><br/>
-    7.2 <a href="#content-attribute-vocabulary">Content Attribute Vocabulary</a><br/>
-        7.2.1 <a href="#content-attribute-id">xml:id</a><br/>
-        7.2.2 <a href="#content-attribute-lang">xml:lang</a><br/>
-        7.2.3 <a href="#content-attribute-space">xml:space</a><br/>
-8 <a href="#styling">Styling</a><br/>
-    8.1 <a href="#styling-element-vocabulary">Styling Element Vocabulary</a><br/>
-        8.1.1 <a href="#styling-vocabulary-styling">styling</a><br/>
-        8.1.2 <a href="#styling-vocabulary-style">style</a><br/>
-    8.2 <a href="#styling-attribute-vocabulary">Styling Attribute Vocabulary</a><br/>
-        8.2.1 <a href="#style-attribute-style">style</a><br/>
-        8.2.2 <a href="#style-attribute-backgroundColor">tts:backgroundColor</a><br/>
-        8.2.3 <a href="#style-attribute-color">tts:color</a><br/>
-        8.2.4 <a href="#style-attribute-direction">tts:direction</a><br/>
-        8.2.5 <a href="#style-attribute-display">tts:display</a><br/>
-        8.2.6 <a href="#style-attribute-displayAlign">tts:displayAlign</a><br/>
-        8.2.7 <a href="#style-attribute-extent">tts:extent</a><br/>
-        8.2.8 <a href="#style-attribute-fontFamily">tts:fontFamily</a><br/>
-        8.2.9 <a href="#style-attribute-fontSize">tts:fontSize</a><br/>
-        8.2.10 <a href="#style-attribute-fontStyle">tts:fontStyle</a><br/>
-        8.2.11 <a href="#style-attribute-fontWeight">tts:fontWeight</a><br/>
-        8.2.12 <a href="#style-attribute-lineHeight">tts:lineHeight</a><br/>
-        8.2.13 <a href="#style-attribute-opacity">tts:opacity</a><br/>
-        8.2.14 <a href="#style-attribute-origin">tts:origin</a><br/>
-        8.2.15 <a href="#style-attribute-overflow">tts:overflow</a><br/>
-        8.2.16 <a href="#style-attribute-padding">tts:padding</a><br/>
-        8.2.17 <a href="#style-attribute-showBackground">tts:showBackground</a><br/>
-        8.2.18 <a href="#style-attribute-textAlign">tts:textAlign</a><br/>
-        8.2.19 <a href="#style-attribute-textDecoration">tts:textDecoration</a><br/>
-        8.2.20 <a href="#style-attribute-textOutline">tts:textOutline</a><br/>
-        8.2.21 <a href="#style-attribute-unicodeBidi">tts:unicodeBidi</a><br/>
-        8.2.22 <a href="#style-attribute-visibility">tts:visibility</a><br/>
-        8.2.23 <a href="#style-attribute-wrapOption">tts:wrapOption</a><br/>
-        8.2.24 <a href="#style-attribute-writingMode">tts:writingMode</a><br/>
-        8.2.25 <a href="#style-attribute-zIndex">tts:zIndex</a><br/>
-    8.3 <a href="#styling-style-value-expressions">Style Value Expressions</a><br/>
-        8.3.1 <a href="#style-value-alpha">&lt;alpha&gt;</a><br/>
-        8.3.2 <a href="#style-value-color">&lt;color&gt;</a><br/>
-        8.3.3 <a href="#style-value-digit">&lt;digit&gt;</a><br/>
-        8.3.4 <a href="#style-value-duration">&lt;duration&gt;</a><br/>
-        8.3.5 <a href="#style-value-familyName">&lt;familyName&gt;</a><br/>
-        8.3.6 <a href="#style-value-genericFamilyName">&lt;genericFamilyName&gt;</a><br/>
-        8.3.7 <a href="#style-value-hexDigit">&lt;hexDigit&gt;</a><br/>
-        8.3.8 <a href="#style-value-integer">&lt;integer&gt;</a><br/>
-        8.3.9 <a href="#style-value-length">&lt;length&gt;</a><br/>
-        8.3.10 <a href="#style-value-namedColor">&lt;namedColor&gt;</a><br/>
-        8.3.11 <a href="#style-value-quotedString">&lt;quotedString&gt;</a><br/>
-        8.3.12 <a href="#style-value-string">&lt;string&gt;</a><br/>
-    8.4 <a href="#semantics-style-resolution">Style Resolution</a><br/>
-        8.4.1 <a href="#semantics-style-association">Style Association</a><br/>
-            8.4.1.1 <a href="#semantics-style-association-inline">Inline Styling</a><br/>
-            8.4.1.2 <a href="#semantics-style-association-referential">Referential Styling</a><br/>
-            8.4.1.3 <a href="#semantics-style-association-chained-referential">Chained Referential Styling</a><br/>
-            8.4.1.4 <a href="#semantics-style-association-nested">Nested Styling</a><br/>
-        8.4.2 <a href="#semantics-style-inheritance">Style Inheritance</a><br/>
-            8.4.2.1 <a href="#semantics-style-inheritance-content">Content Style Inheritance</a><br/>
-            8.4.2.2 <a href="#semantics-style-inheritance-region">Region Style Inheritance</a><br/>
-        8.4.3 <a href="#semantics-style-resolution-value-categories">Style Resolution Value Categories</a><br/>
-            8.4.3.1 <a href="#semantics-style-resolved-value-category-specified">Specified Values</a><br/>
-            8.4.3.2 <a href="#semantics-style-resolved-value-category-computed">Computed Values</a><br/>
-            8.4.3.3 <a href="#semantics-style-resolved-value-category-actual">Actual Values</a><br/>
-        8.4.4 <a href="#semantics-style-resolution-processing">Style Resolution Processing</a><br/>
-            8.4.4.1 <a href="#semantics-style-resolution-processing-definitions">Conceptual Definitions</a><br/>
-            8.4.4.2 <a href="#semantics-style-resolution-processing-sss">Specified Style Set Processing</a><br/>
-            8.4.4.3 <a href="#semantics-style-resolution-processing-css">Computed Style Set Processing</a><br/>
-            8.4.4.4 <a href="#semantics-style-resolution-process-overall">Style Resolution Process</a><br/>
-9 <a href="#layout">Layout</a><br/>
-    9.1 <a href="#layout-element-vocabulary">Layout Element Vocabulary</a><br/>
-        9.1.1 <a href="#layout-vocabulary-layout">layout</a><br/>
-        9.1.2 <a href="#layout-vocabulary-region">region</a><br/>
-    9.2 <a href="#layout-attribute-vocabulary">Layout Attribute Vocabulary</a><br/>
-        9.2.1 <a href="#layout-attribute-region">region</a><br/>
-    9.3 <a href="#semantics-region-layout">Region Layout and Presentation</a><br/>
-        9.3.1 <a href="#semantics-default-region">Default Region</a><br/>
-        9.3.2 <a href="#semantics-region-layout-step-1">Intermediate Synchronic Document Construction</a><br/>
-        9.3.3 <a href="#semantics-region-layout-step-2">Synchronic Flow Processing</a><br/>
-        9.3.4 <a href="#semantics-region-layout-example">Elaborated Example (Informative)</a><br/>
-    9.4 <a href="#semantics-line-layout">Line Layout</a><br/>
-10 <a href="#timing">Timing</a><br/>
-    10.1 <a href="#timing-element-vocabulary">Timing Element Vocabulary</a><br/>
-    10.2 <a href="#timing-attribute-vocabulary">Timing Attribute Vocabulary</a><br/>
-        10.2.1 <a href="#timing-attribute-begin">begin</a><br/>
-        10.2.2 <a href="#timing-attribute-end">end</a><br/>
-        10.2.3 <a href="#timing-attribute-dur">dur</a><br/>
-        10.2.4 <a href="#timing-attribute-timeContainer">timeContainer</a><br/>
-    10.3 <a href="#timing-time-value-expressions">Time Value Expressions</a><br/>
-        10.3.1 <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a><br/>
-    10.4 <a href="#timing-time-intervals">Time Intervals</a><br/>
-11 <a href="#animation">Animation</a><br/>
-    11.1 <a href="#animation-element-vocabulary">Animation Element Vocabulary</a><br/>
-        11.1.1 <a href="#animation-vocabulary-set">set</a><br/>
-    11.2 <a href="#animation-attribute-vocabulary">Animation Attribute Vocabulary</a><br/>
-12 <a href="#metadata">Metadata</a><br/>
-    12.1 <a href="#metadata-element-vocabulary">Metadata Element Vocabulary</a><br/>
-        12.1.1 <a href="#metadata-vocabulary-metadata">metadata</a><br/>
-        12.1.2 <a href="#metadata-vocabulary-title">ttm:title</a><br/>
-        12.1.3 <a href="#metadata-vocabulary-desc">ttm:desc</a><br/>
-        12.1.4 <a href="#metadata-vocabulary-copyright">ttm:copyright</a><br/>
-        12.1.5 <a href="#metadata-vocabulary-agent">ttm:agent</a><br/>
-        12.1.6 <a href="#metadata-vocabulary-name">ttm:name</a><br/>
-        12.1.7 <a href="#metadata-vocabulary-actor">ttm:actor</a><br/>
-    12.2 <a href="#metadata-attribute-vocabulary">Metadata Attribute Vocabulary</a><br/>
-        12.2.1 <a href="#metadata-attribute-agent">ttm:agent</a><br/>
-        12.2.2 <a href="#metadata-attribute-role">ttm:role</a><br/>
+formats, TTML Content may be used directly as a distribution format,
+for example, providing a standard content format to reference from a <code>&lt;track&gt;</code>
+element in an HTML5 document, or a <code>&lt;text&gt;</code> or 
+<code>&lt;textstream&gt;</code> media element in a <a href="#smil21">[SMIL 2.1]</a> document.</p></div><div>
+<h2><a id="status"></a>Status of this Document</h2><p><strong>This document is an editor's copy that has
+        no official standing.</strong></p><p></p></div><div class="toc">
+<h2><a id="contents"></a>Table of Contents</h2><p class="toc">1 <a href="#intro">Introduction</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;1.1 <a href="#model">System Model</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;1.2 <a href="#example">Document Example</a><br>
+2 <a href="#definitions">Definitions</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;2.1 <a href="#acronyms">Acronyms</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;2.2 <a href="#terms">Terminology</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;2.3 <a href="#conventions">Documentation Conventions</a><br>
+3 <a href="#conformance">Conformance</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;3.1 <a href="#conformance-content">Content Conformance</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;3.2 <a href="#conformance-processor">Processor Conformance</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3.2.1 <a href="#conformance-generic-processor">Generic Processor Conformance</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3.2.2 <a href="#conformance-transformation-processor">Transformation Processor Conformance</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3.2.3 <a href="#conformance-presentation-processor">Presentation Processor Conformance</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;3.3 <a href="#claims">Claims</a><br>
+4 <a href="#doctypes">Document Types</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;4.1 <a href="#ttml-content-doctype">TTML Content</a><br>
+5 <a href="#vocabulary">Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;5.1 <a href="#vocabulary-namespaces">Namespaces</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;5.2 <a href="#vocabulary-profiles">Profiles</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;5.3 <a href="#vocabulary-overview">Catalog</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;5.3.1 <a href="#core-vocabulary-overview">Core Catalog</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;5.3.2 <a href="#extension-vocabulary-overview">Extension Catalog</a><br>
+6 <a href="#parameters">Parameters</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;6.1 <a href="#parameter-element-vocabulary">Parameter Element Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.1.1 <a href="#parameter-vocabulary-profile">ttp:profile</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.1.2 <a href="#parameter-vocabulary-features">ttp:features</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.1.3 <a href="#parameter-vocabulary-feature">ttp:feature</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.1.4 <a href="#parameter-vocabulary-extensions">ttp:extensions</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.1.5 <a href="#parameter-vocabulary-extension">ttp:extension</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;6.2 <a href="#parameter-attribute-vocabulary">Parameter Attribute Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.1 <a href="#parameter-attribute-cellResolution">ttp:cellResolution</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.2 <a href="#parameter-attribute-clockMode">ttp:clockMode</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.3 <a href="#parameter-attribute-dropMode">ttp:dropMode</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.4 <a href="#parameter-attribute-frameRate">ttp:frameRate</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.5 <a href="#parameter-attribute-frameRateMultiplier">ttp:frameRateMultiplier</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.6 <a href="#parameter-attribute-markerMode">ttp:markerMode</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.7 <a href="#parameter-attribute-pixelAspectRatio">ttp:pixelAspectRatio</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.8 <a href="#parameter-attribute-profile">ttp:profile</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.9 <a href="#parameter-attribute-subFrameRate">ttp:subFrameRate</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.10 <a href="#parameter-attribute-tickRate">ttp:tickRate</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.11 <a href="#parameter-attribute-timeBase">ttp:timeBase</a><br>
+7 <a href="#content">Content</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;7.1 <a href="#content-element-vocabulary">Content Element Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.1.1 <a href="#document-structure-vocabulary-tt">tt</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.1.2 <a href="#document-structure-vocabulary-head">head</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.1.3 <a href="#document-structure-vocabulary-body">body</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.1.4 <a href="#content-vocabulary-div">div</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.1.5 <a href="#content-vocabulary-p">p</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.1.6 <a href="#content-vocabulary-span">span</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.1.7 <a href="#content-vocabulary-br">br</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;7.2 <a href="#content-attribute-vocabulary">Content Attribute Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.2.1 <a href="#content-attribute-id">xml:id</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.2.2 <a href="#content-attribute-lang">xml:lang</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7.2.3 <a href="#content-attribute-space">xml:space</a><br>
+8 <a href="#styling">Styling</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;8.1 <a href="#styling-element-vocabulary">Styling Element Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.1.1 <a href="#styling-vocabulary-styling">styling</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.1.2 <a href="#styling-vocabulary-style">style</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;8.2 <a href="#styling-attribute-vocabulary">Styling Attribute Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.1 <a href="#style-attribute-style">style</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.2 <a href="#style-attribute-backgroundColor">tts:backgroundColor</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.3 <a href="#style-attribute-color">tts:color</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.4 <a href="#style-attribute-direction">tts:direction</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.5 <a href="#style-attribute-display">tts:display</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.6 <a href="#style-attribute-displayAlign">tts:displayAlign</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.7 <a href="#style-attribute-extent">tts:extent</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.8 <a href="#style-attribute-fontFamily">tts:fontFamily</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.9 <a href="#style-attribute-fontSize">tts:fontSize</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.10 <a href="#style-attribute-fontStyle">tts:fontStyle</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.11 <a href="#style-attribute-fontWeight">tts:fontWeight</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.12 <a href="#style-attribute-lineHeight">tts:lineHeight</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.13 <a href="#style-attribute-opacity">tts:opacity</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.14 <a href="#style-attribute-origin">tts:origin</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.15 <a href="#style-attribute-overflow">tts:overflow</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.16 <a href="#style-attribute-padding">tts:padding</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.17 <a href="#style-attribute-showBackground">tts:showBackground</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.18 <a href="#style-attribute-textAlign">tts:textAlign</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.19 <a href="#style-attribute-textDecoration">tts:textDecoration</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.20 <a href="#style-attribute-textOutline">tts:textOutline</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.21 <a href="#style-attribute-unicodeBidi">tts:unicodeBidi</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.22 <a href="#style-attribute-visibility">tts:visibility</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.23 <a href="#style-attribute-wrapOption">tts:wrapOption</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.24 <a href="#style-attribute-writingMode">tts:writingMode</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.25 <a href="#style-attribute-zIndex">tts:zIndex</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;8.3 <a href="#styling-style-value-expressions">Style Value Expressions</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.1 <a href="#style-value-alpha">&lt;alpha&gt;</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.2 <a href="#style-value-color">&lt;color&gt;</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.3 <a href="#style-value-digit">&lt;digit&gt;</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.4 <a href="#style-value-duration">Deleted</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.5 <a href="#style-value-familyName">&lt;familyName&gt;</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.6 <a href="#style-value-genericFamilyName">&lt;genericFamilyName&gt;</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.7 <a href="#style-value-hexDigit">&lt;hexDigit&gt;</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.8 <a href="#style-value-integer">&lt;integer&gt;</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.9 <a href="#style-value-length">&lt;length&gt;</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.10 <a href="#style-value-namedColor">&lt;namedColor&gt;</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.11 <a href="#style-value-quotedString">Deleted</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.3.12 <a href="#style-value-string">Deleted</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;8.4 <a href="#semantics-style-resolution">Style Resolution</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.1 <a href="#semantics-style-association">Style Association</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.1.1 <a href="#semantics-style-association-inline">Inline Styling</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.1.2 <a href="#semantics-style-association-referential">Referential Styling</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.1.3 <a href="#semantics-style-association-chained-referential">Chained Referential Styling</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.1.4 <a href="#semantics-style-association-nested">Nested Styling</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.2 <a href="#semantics-style-inheritance">Style Inheritance</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.2.1 <a href="#semantics-style-inheritance-content">Content Style Inheritance</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.2.2 <a href="#semantics-style-inheritance-region">Region Style Inheritance</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.3 <a href="#semantics-style-resolution-value-categories">Style Resolution Value Categories</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.3.1 <a href="#semantics-style-resolved-value-category-specified">Specified Values</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.3.2 <a href="#semantics-style-resolved-value-category-computed">Computed Values</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.3.3 <a href="#semantics-style-resolved-value-category-actual">Actual Values</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.4 <a href="#semantics-style-resolution-processing">Style Resolution Processing</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.4.1 <a href="#semantics-style-resolution-processing-definitions">Conceptual Definitions</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.4.2 <a href="#semantics-style-resolution-processing-sss">Specified Style Set Processing</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.4.3 <a href="#semantics-style-resolution-processing-css">Computed Style Set Processing</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.4.4.4 <a href="#semantics-style-resolution-process-overall">Style Resolution Process</a><br>
+9 <a href="#layout">Layout</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;9.1 <a href="#layout-element-vocabulary">Layout Element Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9.1.1 <a href="#layout-vocabulary-layout">layout</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9.1.2 <a href="#layout-vocabulary-region">region</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;9.2 <a href="#layout-attribute-vocabulary">Layout Attribute Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9.2.1 <a href="#layout-attribute-region">region</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;9.3 <a href="#semantics-region-layout">Region Layout and Presentation</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9.3.1 <a href="#semantics-default-region">Default Region</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9.3.2 <a href="#semantics-region-layout-step-1">Intermediate Synchronic Document Construction</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9.3.3 <a href="#semantics-region-layout-step-2">Synchronic Flow Processing</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9.3.4 <a href="#semantics-region-layout-example">Elaborated Example (Informative)</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;9.4 <a href="#semantics-line-layout">Line Layout</a><br>
+10 <a href="#timing">Timing</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;10.1 <a href="#timing-element-vocabulary">Timing Element Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;10.2 <a href="#timing-attribute-vocabulary">Timing Attribute Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;10.2.1 <a href="#timing-attribute-begin">begin</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;10.2.2 <a href="#timing-attribute-end">end</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;10.2.3 <a href="#timing-attribute-dur">dur</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;10.2.4 <a href="#timing-attribute-timeContainer">timeContainer</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;10.3 <a href="#timing-time-value-expressions">Time Value Expressions</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;10.3.1 <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;10.4 <a href="#timing-time-intervals">Time Intervals</a><br>
+11 <a href="#animation">Animation</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;11.1 <a href="#animation-element-vocabulary">Animation Element Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;11.1.1 <a href="#animation-vocabulary-set">set</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;11.2 <a href="#animation-attribute-vocabulary">Animation Attribute Vocabulary</a><br>
+12 <a href="#metadata">Metadata</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;12.1 <a href="#metadata-element-vocabulary">Metadata Element Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12.1.1 <a href="#metadata-vocabulary-metadata">metadata</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12.1.2 <a href="#metadata-vocabulary-title">ttm:title</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12.1.3 <a href="#metadata-vocabulary-desc">ttm:desc</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12.1.4 <a href="#metadata-vocabulary-copyright">ttm:copyright</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12.1.5 <a href="#metadata-vocabulary-agent">ttm:agent</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12.1.6 <a href="#metadata-vocabulary-name">ttm:name</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12.1.7 <a href="#metadata-vocabulary-actor">ttm:actor</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;12.2 <a href="#metadata-attribute-vocabulary">Metadata Attribute Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12.2.1 <a href="#metadata-attribute-agent">ttm:agent</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12.2.2 <a href="#metadata-attribute-role">ttm:role</a><br>
 </p>
-<h3><a name="appendices" id="appendices"/>Appendices</h3><p class="toc">A <a href="#reduced-infoset">Reduced XML Infoset</a><br/>
-    A.1 <a href="#reduced-infoset-document">Document Information Item</a><br/>
-    A.2 <a href="#reduced-infoset-element">Element Information Item</a><br/>
-    A.3 <a href="#reduced-infoset-attribute">Attribute Information Item</a><br/>
-    A.4 <a href="#reduced-infoset-character">Character Information Item</a><br/>
-B <a href="#schemas">Schemas</a><br/>
-    B.1 <a href="#dfxp-schema-rnc">Relax NG Schema</a><br/>
-        B.1.1 <a href="#rnc-dfxp-driver-schema">Driver</a><br/>
-        B.1.2 <a href="#rnc-dfxp-modules">Modules</a><br/>
-            B.1.2.1 <a href="#rnc-dfxp-animation-module">Animation Module</a><br/>
-            B.1.2.2 <a href="#rnc-dfxp-classes-module">Classes Module</a><br/>
-            B.1.2.3 <a href="#rnc-dfxp-content-module">Content Module</a><br/>
-            B.1.2.4 <a href="#rnc-dfxp-core-attribs-module">Core Attributes Module</a><br/>
-            B.1.2.5 <a href="#rnc-dfxp-datatypes-module">Data Types Module</a><br/>
-            B.1.2.6 <a href="#rnc-dfxp-document-module">Document Module</a><br/>
-            B.1.2.7 <a href="#rnc-dfxp-head-module">Header Module</a><br/>
-            B.1.2.8 <a href="#rnc-dfxp-layout-module">Layout Module</a><br/>
-            B.1.2.9 <a href="#rnc-dfxp-metadata-module">Metadata Module</a><br/>
-            B.1.2.10 <a href="#rnc-dfxp-metadata-items-module">Metadata Items Module</a><br/>
-            B.1.2.11 <a href="#rnc-dfxp-metadata-attribs-module">Metadata Attributes Module</a><br/>
-            B.1.2.12 <a href="#rnc-dfxp-parameters-module">Parameters Module</a><br/>
-            B.1.2.13 <a href="#rnc-dfxp-parameter-items-module">Parameter Items Module</a><br/>
-            B.1.2.14 <a href="#rnc-dfxp-parameter-attribs-module">Parameter Attributes Module</a><br/>
-            B.1.2.15 <a href="#rnc-dfxp-styling-attribs-module">Styling Attributes Module</a><br/>
-            B.1.2.16 <a href="#rnc-dfxp-styling-module">Styling Module</a><br/>
-            B.1.2.17 <a href="#rnc-dfxp-timing-attribs-module">Timing Attributes Module</a><br/>
-    B.2 <a href="#dfxp-schema-xsd">XML Schema Definition (XSD) Schema</a><br/>
-        B.2.1 <a href="#xsd-dfxp-driver-schema">Driver</a><br/>
-        B.2.2 <a href="#xsd-dfxp-modules">Modules</a><br/>
-            B.2.2.1 <a href="#xsd-dfxp-animation-module">Animation Module</a><br/>
-            B.2.2.2 <a href="#xsd-dfxp-content-module">Content Module</a><br/>
-            B.2.2.3 <a href="#xsd-dfxp-core-attribs-module">Core Attributes Module</a><br/>
-            B.2.2.4 <a href="#xsd-dfxp-datatypes-module">Data Types Module</a><br/>
-            B.2.2.5 <a href="#xsd-dfxp-document-module">Document Module</a><br/>
-            B.2.2.6 <a href="#xsd-dfxp-head-module">Header Module</a><br/>
-            B.2.2.7 <a href="#xsd-dfxp-layout-module">Layout Module</a><br/>
-            B.2.2.8 <a href="#xsd-dfxp-metadata-module">Metadata Module</a><br/>
-            B.2.2.9 <a href="#xsd-dfxp-metadata-items-module">Metadata Items Module</a><br/>
-            B.2.2.10 <a href="#xsd-dfxp-metadata-attribs-module">Metadata Attributes Module</a><br/>
-            B.2.2.11 <a href="#xsd-dfxp-parameters-module">Parameters Module</a><br/>
-            B.2.2.12 <a href="#xsd-dfxp-parameter-items-module">Parameter Items Module</a><br/>
-            B.2.2.13 <a href="#xsd-dfxp-parameter-attribs-module">Parameter Attributes Module</a><br/>
-            B.2.2.14 <a href="#xsd-dfxp-styling-attribs-module">Styling Attributes Module</a><br/>
-            B.2.2.15 <a href="#xsd-dfxp-styling-module">Styling Module</a><br/>
-            B.2.2.16 <a href="#xsd-dfxp-timing-attribs-module">Timing Attributes Module</a><br/>
-            B.2.2.17 <a href="#xsd-dfxp-xml-attrs-module">XML Attributes Module</a><br/>
-C <a href="#media-type-registration">Media Type Registration</a><br/>
-D <a href="#features">Features</a><br/>
-    D.1 <a href="#feature-designations">Feature Designations</a><br/>
-        D.1.1 <a href="#feature-animation">#animation</a><br/>
-        D.1.2 <a href="#feature-backgroundColor">#backgroundColor</a><br/>
-        D.1.3 <a href="#feature-backgroundColor-block">#backgroundColor-block</a><br/>
-        D.1.4 <a href="#feature-backgroundColor-inline">#backgroundColor-inline</a><br/>
-        D.1.5 <a href="#feature-backgroundColor-region">#backgroundColor-region</a><br/>
-        D.1.6 <a href="#feature-bidi">#bidi</a><br/>
-        D.1.7 <a href="#feature-cellResolution">#cellResolution</a><br/>
-        D.1.8 <a href="#feature-clockMode">#clockMode</a><br/>
-        D.1.9 <a href="#feature-clockMode-gps">#clockMode-gps</a><br/>
-        D.1.10 <a href="#feature-clockMode-local">#clockMode-local</a><br/>
-        D.1.11 <a href="#feature-clockMode-utc">#clockMode-utc</a><br/>
-        D.1.12 <a href="#feature-color">#color</a><br/>
-        D.1.13 <a href="#feature-content">#content</a><br/>
-        D.1.14 <a href="#feature-core">#core</a><br/>
-        D.1.15 <a href="#feature-direction">#direction</a><br/>
-        D.1.16 <a href="#feature-display">#display</a><br/>
-        D.1.17 <a href="#feature-display-block">#display-block</a><br/>
-        D.1.18 <a href="#feature-display-inline">#display-inline</a><br/>
-        D.1.19 <a href="#feature-display-region">#display-region</a><br/>
-        D.1.20 <a href="#feature-displayAlign">#displayAlign</a><br/>
-        D.1.21 <a href="#feature-dropMode">#dropMode</a><br/>
-        D.1.22 <a href="#feature-dropMode-dropNTSC">#dropMode-dropNTSC</a><br/>
-        D.1.23 <a href="#feature-dropMode-dropPAL">#dropMode-dropPAL</a><br/>
-        D.1.24 <a href="#feature-dropMode-nonDrop">#dropMode-nonDrop</a><br/>
-        D.1.25 <a href="#feature-extent">#extent</a><br/>
-        D.1.26 <a href="#feature-extent-region">#extent-region</a><br/>
-        D.1.27 <a href="#feature-extent-root">#extent-root</a><br/>
-        D.1.28 <a href="#feature-fontFamily">#fontFamily</a><br/>
-        D.1.29 <a href="#feature-fontFamily-generic">#fontFamily-generic</a><br/>
-        D.1.30 <a href="#feature-fontFamily-non-generic">#fontFamily-non-generic</a><br/>
-        D.1.31 <a href="#feature-fontSize">#fontSize</a><br/>
-        D.1.32 <a href="#feature-fontSize-anamorphic">#fontSize-anamorphic</a><br/>
-        D.1.33 <a href="#feature-fontSize-isomorphic">#fontSize-isomorphic</a><br/>
-        D.1.34 <a href="#feature-fontStyle">#fontStyle</a><br/>
-        D.1.35 <a href="#feature-fontStyle-italic">#fontStyle-italic</a><br/>
-        D.1.36 <a href="#feature-fontStyle-oblique">#fontStyle-oblique</a><br/>
-        D.1.37 <a href="#feature-fontWeight">#fontWeight</a><br/>
-        D.1.38 <a href="#feature-fontWeight-bold">#fontWeight-bold</a><br/>
-        D.1.39 <a href="#feature-frameRate">#frameRate</a><br/>
-        D.1.40 <a href="#feature-frameRateMultiplier">#frameRateMultiplier</a><br/>
-        D.1.41 <a href="#feature-layout">#layout</a><br/>
-        D.1.42 <a href="#feature-length">#length</a><br/>
-        D.1.43 <a href="#feature-length-cell">#length-cell</a><br/>
-        D.1.44 <a href="#feature-length-em">#length-em</a><br/>
-        D.1.45 <a href="#feature-length-integer">#length-integer</a><br/>
-        D.1.46 <a href="#feature-length-negative">#length-negative</a><br/>
-        D.1.47 <a href="#feature-length-percentage">#length-percentage</a><br/>
-        D.1.48 <a href="#feature-length-pixel">#length-pixel</a><br/>
-        D.1.49 <a href="#feature-length-positive">#length-positive</a><br/>
-        D.1.50 <a href="#feature-length-real">#length-real</a><br/>
-        D.1.51 <a href="#feature-lineBreak-uax14">#lineBreak-uax14</a><br/>
-        D.1.52 <a href="#feature-lineHeight">#lineHeight</a><br/>
-        D.1.53 <a href="#feature-markerMode">#markerMode</a><br/>
-        D.1.54 <a href="#feature-markerMode-continuous">#markerMode-continuous</a><br/>
-        D.1.55 <a href="#feature-markerMode-discontinuous">#markerMode-discontinuous</a><br/>
-        D.1.56 <a href="#feature-metadata">#metadata</a><br/>
-        D.1.57 <a href="#feature-nested-div">#nested-div</a><br/>
-        D.1.58 <a href="#feature-nested-span">#nested-span</a><br/>
-        D.1.59 <a href="#feature-opacity">#opacity</a><br/>
-        D.1.60 <a href="#feature-origin">#origin</a><br/>
-        D.1.61 <a href="#feature-overflow">#overflow</a><br/>
-        D.1.62 <a href="#feature-overflow-visible">#overflow-visible</a><br/>
-        D.1.63 <a href="#feature-padding">#padding</a><br/>
-        D.1.64 <a href="#feature-padding-1">#padding-1</a><br/>
-        D.1.65 <a href="#feature-padding-2">#padding-2</a><br/>
-        D.1.66 <a href="#feature-padding-3">#padding-3</a><br/>
-        D.1.67 <a href="#feature-padding-4">#padding-4</a><br/>
-        D.1.68 <a href="#feature-pixelAspectRatio">#pixelAspectRatio</a><br/>
-        D.1.69 <a href="#feature-presentation">#presentation</a><br/>
-        D.1.70 <a href="#feature-profile">#profile</a><br/>
-        D.1.71 <a href="#feature-showBackground">#showBackground</a><br/>
-        D.1.72 <a href="#feature-structure">#structure</a><br/>
-        D.1.73 <a href="#feature-styling">#styling</a><br/>
-        D.1.74 <a href="#feature-styling-chained">#styling-chained</a><br/>
-        D.1.75 <a href="#feature-styling-inheritance-content">#styling-inheritance-content</a><br/>
-        D.1.76 <a href="#feature-styling-inheritance-region">#styling-inheritance-region</a><br/>
-        D.1.77 <a href="#feature-styling-inline">#styling-inline</a><br/>
-        D.1.78 <a href="#feature-styling-nested">#styling-nested</a><br/>
-        D.1.79 <a href="#feature-styling-referential">#styling-referential</a><br/>
-        D.1.80 <a href="#feature-subFrameRate">#subFrameRate</a><br/>
-        D.1.81 <a href="#feature-textAlign">#textAlign</a><br/>
-        D.1.82 <a href="#feature-textAlign-absolute">#textAlign-absolute</a><br/>
-        D.1.83 <a href="#feature-textAlign-relative">#textAlign-relative</a><br/>
-        D.1.84 <a href="#feature-textDecoration">#textDecoration</a><br/>
-        D.1.85 <a href="#feature-textDecoration-over">#textDecoration-over</a><br/>
-        D.1.86 <a href="#feature-textDecoration-through">#textDecoration-through</a><br/>
-        D.1.87 <a href="#feature-textDecoration-under">#textDecoration-under</a><br/>
-        D.1.88 <a href="#feature-textOutline">#textOutline</a><br/>
-        D.1.89 <a href="#feature-textOutline-blurred">#textOutline-blurred</a><br/>
-        D.1.90 <a href="#feature-textOutline-unblurred">#textOutline-unblurred</a><br/>
-        D.1.91 <a href="#feature-tickRate">#tickRate</a><br/>
-        D.1.92 <a href="#feature-timeBase-clock">#timeBase-clock</a><br/>
-        D.1.93 <a href="#feature-timeBase-media">#timeBase-media</a><br/>
-        D.1.94 <a href="#feature-timeBase-smpte">#timeBase-smpte</a><br/>
-        D.1.95 <a href="#feature-timeContainer">#timeContainer</a><br/>
-        D.1.96 <a href="#feature-time-clock">#time-clock</a><br/>
-        D.1.97 <a href="#feature-time-clock-with-frames">#time-clock-with-frames</a><br/>
-        D.1.98 <a href="#feature-time-offset">#time-offset</a><br/>
-        D.1.99 <a href="#feature-time-offset-with-frames">#time-offset-with-frames</a><br/>
-        D.1.100 <a href="#feature-time-offset-with-ticks">#time-offset-with-ticks</a><br/>
-        D.1.101 <a href="#feature-timing">#timing</a><br/>
-        D.1.102 <a href="#feature-transformation">#transformation</a><br/>
-        D.1.103 <a href="#feature-unicodeBidi">#unicodeBidi</a><br/>
-        D.1.104 <a href="#feature-visibility">#visibility</a><br/>
-        D.1.105 <a href="#feature-visibility-block">#visibility-block</a><br/>
-        D.1.106 <a href="#feature-visibility-inline">#visibility-inline</a><br/>
-        D.1.107 <a href="#feature-visibility-region">#visibility-region</a><br/>
-        D.1.108 <a href="#feature-wrapOption">#wrapOption</a><br/>
-        D.1.109 <a href="#feature-writingMode">#writingMode</a><br/>
-        D.1.110 <a href="#feature-writingMode-vertical">#writingMode-vertical</a><br/>
-        D.1.111 <a href="#feature-writingMode-horizontal">#writingMode-horizontal</a><br/>
-        D.1.112 <a href="#feature-writingMode-horizontal-lr">#writingMode-horizontal-lr</a><br/>
-        D.1.113 <a href="#feature-writingMode-horizontal-rl">#writingMode-horizontal-rl</a><br/>
-        D.1.114 <a href="#feature-zIndex">#zIndex</a><br/>
-    D.2 <a href="#feature-support">Feature Support</a><br/>
-E <a href="#extensions">Extensions</a><br/>
-    E.1 <a href="#extension-designations">Extension Designations</a><br/>
-F <a href="#profiles">Profiles</a><br/>
-    F.1 <a href="#profile-dfxp-transformation">DFXP Transformation Profile</a><br/>
-    F.2 <a href="#profile-dfxp-presentation">DFXP Presentation Profile</a><br/>
-    F.3 <a href="#profile-dfxp-full">DFXP Full Profile</a><br/>
-G <a href="#references">References</a><br/>
-H <a href="#other-references">Other References</a> (Non-Normative)<br/>
-I <a href="#requirements">Requirements</a> (Non-Normative)<br/>
-J <a href="#derivation">Vocabulary Derivation</a> (Non-Normative)<br/>
-    J.1 <a href="#d3e17042">Element Derivation</a><br/>
-    J.2 <a href="#d3e17521">Attribute Derivation</a><br/>
-K <a href="#qa">QA Framework Compliance</a> (Non-Normative)<br/>
-    K.1 <a href="#d3e18389">Requirements</a><br/>
-    K.2 <a href="#d3e18553">Guidelines</a><br/>
-L <a href="#streaming">Streaming TTML Content</a> (Non-Normative)<br/>
-M <a href="#acknowledgments">Acknowledgments</a> (Non-Normative)<br/>
-</p></div><hr/><div class="body"><div class="div1">
-<h2><a name="intro" id="intro"/>1 Introduction</h2><p><em>Unless specified otherwise, this section and its sub-sections are non-normative.</em></p><p>The Timed Text Markup Language (TTML) 1.0
+<h3><a id="appendices"></a>Appendices</h3><p class="toc">A <a href="#reduced-infoset">Reduced XML Infoset</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;A.1 <a href="#reduced-infoset-document">Document Information Item</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;A.2 <a href="#reduced-infoset-element">Element Information Item</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;A.3 <a href="#reduced-infoset-attribute">Attribute Information Item</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;A.4 <a href="#reduced-infoset-character">Character Information Item</a><br>
+B <a href="#schemas">Schemas</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;B.1 <a href="#ttml-schema-rnc">Relax NG Compact (RNC) Schema</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;B.2 <a href="#ttml-schema-xsd">XML Schema Definition (XSD) Schema</a><br>
+C <a href="#media-types-registration">Media Type Registration</a><br>
+D <a href="#features">Features</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;D.1 <a href="#feature-designations">Feature Designations</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.1 <a href="#feature-animation">#animation</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.2 <a href="#feature-backgroundColor">#backgroundColor</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.3 <a href="#feature-backgroundColor-block">#backgroundColor-block</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.4 <a href="#feature-backgroundColor-inline">#backgroundColor-inline</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.5 <a href="#feature-backgroundColor-region">#backgroundColor-region</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.6 <a href="#feature-bidi">#bidi</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.7 <a href="#feature-cellResolution">#cellResolution</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.8 <a href="#feature-clockMode">#clockMode</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.9 <a href="#feature-clockMode-gps">#clockMode-gps</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.10 <a href="#feature-clockMode-local">#clockMode-local</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.11 <a href="#feature-clockMode-utc">#clockMode-utc</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.12 <a href="#feature-color">#color</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.13 <a href="#feature-content">#content</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.14 <a href="#feature-core">#core</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.15 <a href="#feature-direction">#direction</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.16 <a href="#feature-display">#display</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.17 <a href="#feature-display-block">#display-block</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.18 <a href="#feature-display-inline">#display-inline</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.19 <a href="#feature-display-region">#display-region</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.20 <a href="#feature-displayAlign">#displayAlign</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.21 <a href="#feature-dropMode">#dropMode</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.22 <a href="#feature-dropMode-dropNTSC">#dropMode-dropNTSC</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.23 <a href="#feature-dropMode-dropPAL">#dropMode-dropPAL</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.24 <a href="#feature-dropMode-nonDrop">#dropMode-nonDrop</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.25 <a href="#feature-extent">#extent</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.26 <a href="#feature-extent-region">#extent-region</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.27 <a href="#feature-extent-root">#extent-root</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.28 <a href="#feature-fontFamily">#fontFamily</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.29 <a href="#feature-fontFamily-generic">#fontFamily-generic</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.30 <a href="#feature-fontFamily-non-generic">#fontFamily-non-generic</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.31 <a href="#feature-fontSize">#fontSize</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.32 <a href="#feature-fontSize-anamorphic">#fontSize-anamorphic</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.33 <a href="#feature-fontSize-isomorphic">#fontSize-isomorphic</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.34 <a href="#feature-fontStyle">#fontStyle</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.35 <a href="#feature-fontStyle-italic">#fontStyle-italic</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.36 <a href="#feature-fontStyle-oblique">#fontStyle-oblique</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.37 <a href="#feature-fontWeight">#fontWeight</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.38 <a href="#feature-fontWeight-bold">#fontWeight-bold</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.39 <a href="#feature-frameRate">#frameRate</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.40 <a href="#feature-frameRateMultiplier">#frameRateMultiplier</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.41 <a href="#feature-layout">#layout</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.42 <a href="#feature-length">#length</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.43 <a href="#feature-length-cell">#length-cell</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.44 <a href="#feature-length-em">#length-em</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.45 <a href="#feature-length-integer">#length-integer</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.46 <a href="#feature-length-negative">#length-negative</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.47 <a href="#feature-length-percentage">#length-percentage</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.48 <a href="#feature-length-pixel">#length-pixel</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.49 <a href="#feature-length-positive">#length-positive</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.50 <a href="#feature-length-real">#length-real</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.51 <a href="#feature-lineBreak-uax14">#lineBreak-uax14</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.52 <a href="#feature-lineHeight">#lineHeight</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.53 <a href="#feature-markerMode">#markerMode</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.54 <a href="#feature-markerMode-continuous">#markerMode-continuous</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.55 <a href="#feature-markerMode-discontinuous">#markerMode-discontinuous</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.56 <a href="#feature-metadata">#metadata</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.57 <a href="#feature-nested-div">#nested-div</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.58 <a href="#feature-nested-span">#nested-span</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.59 <a href="#feature-opacity">#opacity</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.60 <a href="#feature-origin">#origin</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.61 <a href="#feature-overflow">#overflow</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.62 <a href="#feature-overflow-visible">#overflow-visible</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.63 <a href="#feature-padding">#padding</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.64 <a href="#feature-padding-1">#padding-1</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.65 <a href="#feature-padding-2">#padding-2</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.66 <a href="#feature-padding-3">#padding-3</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.67 <a href="#feature-padding-4">#padding-4</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.68 <a href="#feature-pixelAspectRatio">#pixelAspectRatio</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.69 <a href="#feature-presentation">#presentation</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.70 <a href="#feature-profile">#profile</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.71 <a href="#feature-showBackground">#showBackground</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.72 <a href="#feature-structure">#structure</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.73 <a href="#feature-styling">#styling</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.74 <a href="#feature-styling-chained">#styling-chained</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.75 <a href="#feature-styling-inheritance-content">#styling-inheritance-content</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.76 <a href="#feature-styling-inheritance-region">#styling-inheritance-region</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.77 <a href="#feature-styling-inline">#styling-inline</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.78 <a href="#feature-styling-nested">#styling-nested</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.79 <a href="#feature-styling-referential">#styling-referential</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.80 <a href="#feature-subFrameRate">#subFrameRate</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.81 <a href="#feature-textAlign">#textAlign</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.82 <a href="#feature-textAlign-absolute">#textAlign-absolute</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.83 <a href="#feature-textAlign-relative">#textAlign-relative</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.84 <a href="#feature-textDecoration">#textDecoration</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.85 <a href="#feature-textDecoration-over">#textDecoration-over</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.86 <a href="#feature-textDecoration-through">#textDecoration-through</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.87 <a href="#feature-textDecoration-under">#textDecoration-under</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.88 <a href="#feature-textOutline">#textOutline</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.89 <a href="#feature-textOutline-blurred">#textOutline-blurred</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.90 <a href="#feature-textOutline-unblurred">#textOutline-unblurred</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.91 <a href="#feature-tickRate">#tickRate</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.92 <a href="#feature-timeBase-clock">#timeBase-clock</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.93 <a href="#feature-timeBase-media">#timeBase-media</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.94 <a href="#feature-timeBase-smpte">#timeBase-smpte</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.95 <a href="#feature-timeContainer">#timeContainer</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.96 <a href="#feature-time-clock">#time-clock</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.97 <a href="#feature-time-clock-with-frames">#time-clock-with-frames</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.98 <a href="#feature-time-offset">#time-offset</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.99 <a href="#feature-time-offset-with-frames">#time-offset-with-frames</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.100 <a href="#feature-time-offset-with-ticks">#time-offset-with-ticks</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.101 <a href="#feature-timing">#timing</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.102 <a href="#feature-transformation">#transformation</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.103 <a href="#feature-unicodeBidi">#unicodeBidi</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.104 <a href="#feature-visibility">#visibility</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.105 <a href="#feature-visibility-block">#visibility-block</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.106 <a href="#feature-visibility-inline">#visibility-inline</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.107 <a href="#feature-visibility-region">#visibility-region</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.108 <a href="#feature-wrapOption">#wrapOption</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.109 <a href="#feature-writingMode">#writingMode</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.110 <a href="#feature-writingMode-vertical">#writingMode-vertical</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.111 <a href="#feature-writingMode-horizontal">#writingMode-horizontal</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.112 <a href="#feature-writingMode-horizontal-lr">#writingMode-horizontal-lr</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.113 <a href="#feature-writingMode-horizontal-rl">#writingMode-horizontal-rl</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.1.114 <a href="#feature-zIndex">#zIndex</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;D.2 <a href="#feature-support">Feature Support</a><br>
+E <a href="#extensions">Extensions</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;E.1 <a href="#extension-designations">Extension Designations</a><br>
+F <a href="#profiles">Profiles</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;F.1 <a href="#profile-dfxp-transformation">DFXP Transformation Profile</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;F.2 <a href="#profile-dfxp-presentation">DFXP Presentation Profile</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;F.3 <a href="#profile-dfxp-full">DFXP Full Profile</a><br>
+G <a href="#references">References</a><br>
+H <a href="#other-references">Other References</a> (Non-Normative)<br>
+I <a href="#requirements">Requirements</a> (Non-Normative)<br>
+J <a href="#derivation">Vocabulary Derivation</a> (Non-Normative)<br>
+&nbsp;&nbsp;&nbsp;&nbsp;J.1 <a href="#d3e18582">Element Derivation</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;J.2 <a href="#d3e19061">Attribute Derivation</a><br>
+K <a href="#qa">QA Framework Compliance</a> (Non-Normative)<br>
+&nbsp;&nbsp;&nbsp;&nbsp;K.1 <a href="#d3e19947">Requirements</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;K.2 <a href="#d3e20111">Guidelines</a><br>
+L <a href="#streaming">Streaming TTML Content</a> (Non-Normative)<br>
+M <a href="#concrete-encoding">Concrete Encoding</a> (Non-Normative)<br>
+N <a href="#time-expression-semantics">Time Expression Semantics</a> (Non-Normative)<br>
+&nbsp;&nbsp;&nbsp;&nbsp;N.1 <a href="#time-expression-semantics-clock">Clock Time Base</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;N.2 <a href="#time-expression-semantics-media">Media Time Base</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;N.3 <a href="#time-expression-semantics-smpte">SMPTE Time Base</a><br>
+O <a href="#common-styling">Common Caption Style Examples</a> (Non-Normative)<br>
+&nbsp;&nbsp;&nbsp;&nbsp;O.1 <a href="#pop-on-example">Pop-On Caption Example</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;O.2 <a href="#roll-up-example">Roll-Up Caption Example</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;O.3 <a href="#paint-on-example">Paint-On Caption Example</a><br>
+P <a href="#acknowledgments">Acknowledgments</a> (Non-Normative)<br>
+</p></div><hr><div class="body"><div class="div1">
+<h2><a id="intro"></a>1 Introduction</h2><p><em>Unless specified otherwise, this section and its sub-sections are non-normative.</em></p><p>The Timed Text Markup Language (TTML) 1.0
 provides a standardized representation of a particular subset of
 textual information with which stylistic, layout, and timing semantics are associated by
-an author or an authoring system for the purpose of interchange and potential presentation.</p><p>TTML is expressly designed to meet only a limited set of requirements
+an author or an authoring system for the purpose of interchange and processing.</p><p>TTML is expressly designed to meet only a limited set of requirements
 established by <a href="#ttaf1-req">[TTAF1-REQ]</a>, and summarized in <a href="#requirements"><b>I Requirements</b></a>. In particular, only those requirements which service the
 need of performing interchange with existing, legacy distribution systems are
 satisfied.</p><p>In addition to being used for interchange among legacy distribution content
-formats, TTML content may be used directly as a distribution format, providing, for
-example, a standard content format to reference from a <code>&lt;text&gt;</code> or 
-<code>&lt;textstream&gt;</code> media object element in a <a href="#smil21">[SMIL 2.1]</a> document. Certain properties of TTML support
-streamability of content, as described in <a href="#streaming"><b>L Streaming TTML Content</b></a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>While TTML was not expressly designed for direct (embedded) integration into a
-SMIL document instance, such integration is not precluded.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>In some contexts of use, it may be appropriate to employ
+formats, TTML Content may be used directly as a distribution format (as implied by
+the acronym DFXP), providing, for
+example, a standard content format to reference from a <code>&lt;track&gt;</code>
+element in an HTML5 document, or a <code>&lt;text&gt;</code> or 
+<code>&lt;textstream&gt;</code> media element in a <a href="#smil21">[SMIL 2.1]</a> document. Certain properties of TTML support
+streamability of content, as described in <a href="#streaming"><b>L Streaming TTML Content</b></a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>While TTML was not expressly designed for direct (embedded) integration into an
+HTML or a SMIL document instance, such integration is not precluded.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>In some contexts of use, it may be appropriate to employ
 animated content to depict sign language representations of the same content
-as expressed by a Timed Text document instance. This use case is not
+as expressed by a Timed Text <em>Document Instance</em>. This use case is not
 explicitly addressed by TTML mechanisms, but may be addressed by some
-external multimedia integration technology, such as SMIL.</p></div><div class="div2">
-<h3><a name="model" id="model"/>1.1 System Model</h3><p>Use of TTML is intended to function in a wider context of Timed Text
-Authoring and Distribution mechanisms that are based upon a system
-model, depicted in <a href="#model-graphic"><b>Figure 1 – System Model</b></a>, wherein the Timed Text Markup Language
+external multimedia integration technology, such as SMIL.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>In previous drafts of this specification, TTML was referred to as DFXP (Distribution
+Format Exchange Profile). This latter term is retained for historical reasons in
+certain contexts, such as profile names and designators, and the short name
+<code>ttaf1-dfxp</code> used in URLs to refer to this specification.</p></div><div class="div2">
+<h3><a id="model"></a>1.1 System Model</h3><p>Use of TTML is intended to function in a wider context of Timed Text
+Authoring and Distribution mechanisms that are based upon the system
+model depicted in <a href="#model-graphic"><b>Figure 1 – System Model</b></a>, wherein the Timed Text Markup Language
 serves as a bidirectional interchange format among a heterogeneous collection of
 authoring systems, and as a unidirectional interchange format to a
 heterogeneous collection of distribution formats after undergoing transcoding
 or compilation to the target distribution formats as required, and where one
-particular distribution format is TTML.</p><table summary="HTML Table" id="model-graphic" class="example-images"><caption>Figure 1 – System Model</caption><tbody><tr><td><img src="images/model.png" alt="System Model"/></td></tr></tbody></table></div><div class="div2">
-<h3><a name="example" id="example"/>1.2 Document Example</h3><p>A TTML document instance consists of a <code>tt</code> document element that contains
+particular distribution format is TTML (labeled as "DFXP" in the figure).</p><a id="model-graphic"></a><table class="example-images"><caption>Figure 1 – System Model</caption><tbody><tr><td><img src="images/model.png" alt="System Model"></td></tr></tbody></table></div><div class="div2">
+<h3><a id="example"></a>1.2 Document Example</h3><p>A TTML <em>Document Instance</em> consists of a <code>tt</code> document element that contains
 a header and a body, where the header specifies document level metadata, styling
 definitions and layout definitions, and the body specifies text content intermixed
-with references to style and layout information and inline timing information.</p><table summary="HTML Table" id="dfxp-example-document-structure" class="example"><caption>Example Fragment – TTML Document Structure</caption><tbody><tr><td>
+with references to style and layout information and inline styling and timing information.</p><a id="ttml-example-document-structure"></a><table class="example"><caption>Example Fragment – TTML Document Structure</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;tt xml:lang="" xmlns="http://www.w3.org/ns/ttml"&gt;
   &lt;head&gt;
@@ -464,7 +454,7 @@
 </pre></div>
 </td></tr></tbody></table><p>Document level metadata may specify a document title, description,
 and copyright information. In addition, arbitrary metadata drawn from
-other namespaces may be specified.</p><table summary="HTML Table" id="dfxp-example-metadata" class="example"><caption>Example Fragment – TTML Metadata</caption><tbody><tr><td>
+other namespaces may be specified.</p><a id="ttml-example-metadata"></a><table class="example"><caption>Example Fragment – TTML Metadata</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;metadata xmlns:ttm="http://www.w3.org/ns/ttml#metadata"&gt;
   &lt;ttm:title&gt;Timed Text TTML Example&lt;/ttm:title&gt;
@@ -472,8 +462,9 @@
 &lt;/metadata&gt;
 </pre></div>
 </td></tr></tbody></table><p>Styling information may be specified in the form of style specification
-definitions that are referenced by layout and content information.</p><p>In <a href="#dfxp-example-styling"><b>Example Fragment – TTML Styling</b></a>, four style sets of specifications
-are defined, with one set serving as a collection of default styles.</p><table summary="HTML Table" id="dfxp-example-styling" class="example"><caption>Example Fragment – TTML Styling</caption><tbody><tr><td>
+definitions that are referenced by layout and content information,
+specified inline with content information, or both.</p><p>In <a href="#ttml-example-styling"><b>Example Fragment – TTML Styling</b></a>, four style sets of specifications
+are defined, with one set serving as a collection of default styles.</p><a id="ttml-example-styling"></a><table class="example"><caption>Example Fragment – TTML Styling</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;styling xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
   &lt;!-- s1 specifies default color, font, and text alignment --&gt;
@@ -495,11 +486,12 @@
 is intended to be presented. A region definition may reference one or
 more sets of style specifications in order to permit content flowed in the
 region to inherit from these styles.
-In <a href="#dfxp-example-layout"><b>Example Fragment – TTML Layout</b></a>, the region definition makes
-reference to style specification <code>s1</code> which allows all content
-flowed into the region to inherit from the region's styles (in the case
+In <a href="#ttml-example-layout"><b>Example Fragment – TTML Layout</b></a>, the region definition makes
+reference to style specification <code>s1</code> augmented by specific inline
+styles which, together, allow content flowed into the region to inherit
+from the region's styles (in the case
 that a style is not already explicitly specified on content or inherited
-via the content hierarchy.)</p><table summary="HTML Table" id="dfxp-example-layout" class="example"><caption>Example Fragment – TTML Layout</caption><tbody><tr><td>
+via the content hierarchy.)</p><a id="ttml-example-layout"></a><table class="example"><caption>Example Fragment – TTML Layout</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;layout xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
   &lt;region xml:id="subtitleArea"
@@ -511,16 +503,16 @@
   /&gt;
 &lt;/layout&gt;  
 </pre></div>
-</td></tr></tbody></table><p>The content of a TTML document instance is expressed in its
+</td></tr></tbody></table><p>The content of a <em>Document Instance</em> is expressed in its
 body, which is organized in terms of block and inline text elements.
 The hierarchical organization of content elements serves a primary role in
 determining both spatial and temporal relationships. For example, in
-<a href="#dfxp-example-body"><b>Example Fragment – TTML Body</b></a>, each paragraph (<code>p</code> element)
+<a href="#ttml-example-body"><b>Example Fragment – TTML Body</b></a>, each paragraph (<code>p</code> element)
 is flowed into its target region in the specified lexical order; furthermore,
 the active time interval of each paragraph is timed in accordance to its
 parent or sibling according to the applicable time containment semantics —
-in this case, the division parent is interpreted as a parallel time
-container.</p><table summary="HTML Table" id="dfxp-example-body" class="example"><caption>Example Fragment – TTML Body</caption><tbody><tr><td>
+in this case, the division parent is interpreted (by default) as a parallel time
+container.</p><a id="ttml-example-body"></a><table class="example"><caption>Example Fragment – TTML Body</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;body region="subtitleArea"&gt;
   &lt;div&gt;
@@ -565,14 +557,14 @@
   &lt;/div&gt;    
 &lt;/body&gt;
 </pre></div>
-</td></tr></tbody></table><p>The first subtitle <a href="#dfxp-example-subtitle-1"><b>Subtitle 1 – Time Interval [0.76, 3.45)</b></a> is
+</td></tr></tbody></table><p>The first subtitle <a href="#ttml-example-subtitle-1"><b>Subtitle 1 – Time Interval [0.76, 3.45)</b></a> is
 presented during the time interval 0.76 to 3.45 seconds.
 This
 subtitle inherits its font family, font size,
 foreground color, and text alignment from the region into which it is
 presented. Since no region is explicitly specified on the paragraph,
 the nearest ancestor that specifies a region determines the
-region. Note also that content is presented
+targeted region. Note also that content is presented
 at the bottom (after edge) of the containing region due to the <code>tts:displayAlign="after"</code>
 being specified on the region definition.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The notation "[<em>X</em>,<em>Y</em>]" denotes a closed
 interval from <em>X</em> to <em>Y</em>, including
@@ -586,64 +578,111 @@
 "(<em>X</em>,<em>Y</em>)" denotes an open
 interval from <em>X</em> to <em>Y</em>, not including
 <em>X</em> or <em>Y</em>.
-</p></div><table summary="HTML Table" id="dfxp-example-subtitle-1" class="example-images"><caption>Subtitle 1 – Time Interval [0.76, 3.45)</caption><tbody><tr><td><img src="images/subtitle1.png" alt="Subtitle 1"/></td></tr></tbody></table><p>The second subtitle continues with the default style, except that it contains
+</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>In this example, the <code>p</code> element is used as a presentational
+element rather than as a semantic element, i.e., as a linguistic paragraph.
+It is up to an author to determine which TTML elements are used to convey
+the intended meaning. For instance, this example could be written to use
+timing on <code>span</code> elements in order to preserve the integrity of
+semantic paragraphs.</p></div><a id="ttml-example-subtitle-1"></a><table class="example-images"><caption>Subtitle 1 – Time Interval [0.76, 3.45)</caption><tbody><tr><td><img src="images/subtitle1.png" alt="Subtitle 1"></td></tr></tbody></table><p>The second subtitle continues with the default style, except that it contains
 two lines of text with an intervening author-specified line break. Note the effects of
 the use of <code>tts:textAlign="center"</code> to specify the paragraph's alignment
-in the inline progression direction.</p><table summary="HTML Table" id="dfxp-example-subtitle-2" class="example-images"><caption>Subtitle 2 – Time Interval [5.0, 10.0)</caption><tbody><tr><td><img src="images/subtitle2.png" alt="Subtitle 2"/></td></tr></tbody></table><p>The third subtitle continues, using a variant style which overrides the default style's
-foreground color with a different color.</p><table summary="HTML Table" id="dfxp-example-subtitle-3" class="example-images"><caption>Subtitle 3 – Time Interval [10.0, 16.0)</caption><tbody><tr><td><img src="images/subtitle3.png" alt="Subtitle 3"/></td></tr></tbody></table><p>The fourth subtitle reverts to the default style.</p><table summary="HTML Table" id="dfxp-example-subtitle-4" class="example-images"><caption>Subtitle 4 – Time Interval [17.2, 23.0)</caption><tbody><tr><td><img src="images/subtitle4.png" alt="Subtitle 4"/></td></tr></tbody></table><p>The fifth subtitle continues, again using a variant style which
-overrides the default style's foreground color with a different color.</p><table summary="HTML Table" id="dfxp-example-subtitle-5" class="example-images"><caption>Subtitle 5 – Time Interval [23.0, 27.0)</caption><tbody><tr><td><img src="images/subtitle5.png" alt="Subtitle 5"/></td></tr></tbody></table><p>During the next active time interval, two distinct subtitles are simultaneously active, with
-the paragraph expressing each subtitle using a different style that overrides color and paragraph
+in the inline progression direction.</p><a id="ttml-example-subtitle-2"></a><table class="example-images"><caption>Subtitle 2 – Time Interval [5.0, 10.0)</caption><tbody><tr><td><img src="images/subtitle2.png" alt="Subtitle 2"></td></tr></tbody></table><p>The third subtitle continues, using a variant style which overrides the default style's
+foreground color with a different color.</p><a id="ttml-example-subtitle-3"></a><table class="example-images"><caption>Subtitle 3 – Time Interval [10.0, 16.0)</caption><tbody><tr><td><img src="images/subtitle3.png" alt="Subtitle 3"></td></tr></tbody></table><p>The fourth subtitle reverts to the default style.</p><a id="ttml-example-subtitle-4"></a><table class="example-images"><caption>Subtitle 4 – Time Interval [17.2, 23.0)</caption><tbody><tr><td><img src="images/subtitle4.png" alt="Subtitle 4"></td></tr></tbody></table><p>The fifth subtitle continues, again using a variant style which
+overrides the default style's foreground color with a different color.</p><a id="ttml-example-subtitle-5"></a><table class="example-images"><caption>Subtitle 5 – Time Interval [23.0, 27.0)</caption><tbody><tr><td><img src="images/subtitle5.png" alt="Subtitle 5"></td></tr></tbody></table><p>During the next active time interval, two distinct subtitles are simultaneously active, with
+the paragraphs expressing each subtitle using different styles that override color and paragraph
 text alignment of the default style. Note that the flow order is determined by the lexical
-order of elements as they appear in the content hierarchy.</p><table summary="HTML Table" id="dfxp-example-subtitle-6" class="example-images"><caption>Subtitles 6a and 6b – Time Interval [28.0, 34.6)</caption><tbody><tr><td><img src="images/subtitle6.png" alt="Subtitles 6a and 6b"/></td></tr></tbody></table><p>The next subtitle is specified in a similar manner using
-a style override to give a paragraph right (end) justified in the
-inline progression direction.</p><table summary="HTML Table" id="dfxp-example-subtitle-7" class="example-images"><caption>Subtitle 7 – Time Interval [34.6, 45.0)</caption><tbody><tr><td><img src="images/subtitle7.png" alt="Subtitles 7a and 7b"/></td></tr></tbody></table><p>The eighth subtitle uses the same style override as the previous
+order of elements as they appear in the content hierarchy.</p><a id="ttml-example-subtitle-6"></a><table class="example-images"><caption>Subtitles 6a and 6b – Time Interval [28.0, 34.6)</caption><tbody><tr><td><img src="images/subtitle6.png" alt="Subtitles 6a and 6b"></td></tr></tbody></table><p>The next subtitle is specified in a similar manner using
+a style override to give the paragraph right (end) justification in the
+inline progression direction.</p><a id="ttml-example-subtitle-7"></a><table class="example-images"><caption>Subtitle 7 – Time Interval [34.6, 45.0)</caption><tbody><tr><td><img src="images/subtitle7.png" alt="Subtitles 7a and 7b"></td></tr></tbody></table><p>The eighth subtitle uses the same style override as the previous
 subtitle in order to maintain the right (end) justification of the
-paragraph.</p><table summary="HTML Table" id="dfxp-example-subtitle-8" class="example-images"><caption>Subtitle 8 – Time Interval [47.3, 49.0)</caption><tbody><tr><td><img src="images/subtitle8.png" alt="Subtitle 8"/></td></tr></tbody></table><p>During the final (ninth) active time interval, two distinct
+paragraph.</p><a id="ttml-example-subtitle-8"></a><table class="example-images"><caption>Subtitle 8 – Time Interval [47.3, 49.0)</caption><tbody><tr><td><img src="images/subtitle8.png" alt="Subtitle 8"></td></tr></tbody></table><p>During the final (ninth) active time interval, two distinct
 subtitles are again simultaneously active, but with a different
 style applied to the second paragraph to override the default color.
 Note that the flow order is determined by the lexical order of
-elements as they appear in the content hierarchy.</p><table summary="HTML Table" id="dfxp-example-subtitle-9" class="example-images"><caption>Subtitles 9a and 9b – Time Interval [53.5, 58.7)</caption><tbody><tr><td><img src="images/subtitle9.png" alt="Subtitles 9a and 9b"/></td></tr></tbody></table><p>The examples shown above demonstrate the primary types of information that may
+elements as they appear in the content hierarchy.</p><a id="ttml-example-subtitle-9"></a><table class="example-images"><caption>Subtitles 9a and 9b – Time Interval [53.5, 58.7)</caption><tbody><tr><td><img src="images/subtitle9.png" alt="Subtitles 9a and 9b"></td></tr></tbody></table><p>The examples shown above demonstrate the primary types of information that may
 be authored using TTML: metadata, styling, layout, timing, and content. In typical cases,
-styling and layout information are separately specified in a document instance. Content information
+styling and layout information are separately specified in a <em>Document Instance</em>. Content information
 is expressed in a hierarchical fashion that embodies the organization of both spatial (flow) and
 timing information. Content makes direct or indirect references to styling and layout information
 and may specify inline overrides to styling.</p></div></div><div class="div1">
-<h2><a name="definitions" id="definitions"/>2 Definitions</h2><div class="div2">
-<h3><a name="acronyms" id="acronyms"/>2.1 Acronyms</h3><table class="acronyms" summary="Glossary List"><tr><td class="label"><b>DFXP</b></td><td class="def"><p>Distribution Format Exchange Profile</p></td></tr><tr><td class="label"><b>TT</b></td><td class="def"><p>Timed Text</p></td></tr><tr><td class="label"><b>TTML</b></td><td class="def"><p>Timed Text Markup Language</p></td></tr><tr><td class="label"><b>TT AS</b></td><td class="def"><p>Timed Text Authoring System</p></td></tr><tr><td class="label"><b>TT AF</b></td><td class="def"><p>Timed Text Authoring Format</p></td></tr><tr><td class="label"><b>TT WG</b></td><td class="def"><p>Timed Text Working Group</p></td></tr></table></div><div class="div2">
-<h3><a name="terms" id="terms"/>2.2 Terminology</h3><dl><dt class="label">Abstract Document Instance</dt><dd><p>An instance of an abstract data set as represented by a
+<h2><a id="definitions"></a>2 Definitions</h2><div class="div2">
+<h3><a id="acronyms"></a>2.1 Acronyms</h3><table class="acronyms" summary="Glossary List"><tr><td class="label"><b>DFXP</b></td><td class="def"><p>Distribution Format Exchange Profile</p></td></tr><tr><td class="label"><b>TT</b></td><td class="def"><p>Timed Text</p></td></tr><tr><td class="label"><b>TTML</b></td><td class="def"><p>Timed Text Markup Language</p></td></tr><tr><td class="label"><b>TTAF</b></td><td class="def"><p>Timed Text Authoring Format</p></td></tr><tr><td class="label"><b>TTWG</b></td><td class="def"><p>Timed Text Working Group</p></td></tr></table></div><div class="div2">
+<h3><a id="terms"></a>2.2 Terminology</h3><dl><dt class="label">Abstract Document Instance</dt><dd><p>An instance of an abstract data set as represented by a
 <em>Reduced XML Infoset</em>.</p></dd><dt class="label">Abstract Document Type</dt><dd><p>A set of constraints that defines a class of <em>XML Information
-Set</em>s <a href="#infoset">[XML InfoSet]</a>.</p></dd><dt class="label">Attribute Information Item</dt><dd><p>Each specified or defaulted attribute  of an XML document corresponds with an attribute information
+Sets</em> <a href="#infoset">[XML InfoSet]</a>.</p></dd><dt class="label">Attribute Information Item</dt><dd><p>Each specified or defaulted attribute  of an XML document corresponds with an attribute information
 item as defined by <a href="#infoset">[XML InfoSet]</a>, §2.3.</p></dd><dt class="label">Character Information Item</dt><dd><p>Each data character appearing in an XML document corresponds with a character information
-item as defined by <a href="#infoset">[XML InfoSet]</a>, §2.6.</p></dd><dt class="label">Content Processor</dt><dd><p>A processing system capable of importing (receiving) Timed Text Markup Language
+item as defined by <a href="#infoset">[XML InfoSet]</a>, §2.6.</p></dd><dt class="label">Computed Cell Size</dt><dd><p>The size (extent) of a cell computed by dividing the width of the <em>Root Container
+Region</em> by the column count, i.e., the number of cells in the horizontal axis, and by dividing
+the height of the <em>Root Container Region</em> by the row count, i.e., the number of cells in the vertical
+axis, where the column and row counts are determined by the <code>ttp:cellResolution</code> parameter attribute.</p></dd><dt class="label">Content Processor</dt><dd><p>A processing system capable of importing (receiving) Timed Text Markup Language
 content for the purpose of transforming, presenting, or otherwise processing the content.</p></dd><dt class="label">Content Profile</dt><dd><p>A collection of features and extensions that are (or may be) employed by
 Timed Text Markup Language content.</p></dd><dt class="label">Content Region</dt><dd><p>A logical region into which rendered content is placed when modeling or
-performing presentation processing.</p></dd><dt class="label">Element Information Item</dt><dd><p>Each element appearing in an XML document corresponds with an element information
+performing presentation processing.</p></dd><dt class="label">Document Instance</dt><dd><p>A concrete realization of a Timed Text Markup Language document, where the concrete form
+is specific to the context of reference. For example, a sequence of bytes that represents an
+XML serialization of a Timed Text document, an internal, parsed representation of such a
+Timed Text document, etc.</p></dd><dt class="label">Document Interchange Context</dt><dd><p>The implied context or environment external to a <em>Content Processor</em> in
+which document interchange occurs, and in which out-of-band protocols or specifications
+may define certain behavioral defaults, such as an implied <em>Content Profile</em>.</p></dd><dt class="label">Document Processing Context</dt><dd><p>The implied context or environment internal to a <em>Content Processor</em> in
+which document processing occurs, and in which out-of-band protocols or specifications
+may define certain behavioral defaults, such as the establishment or creation of a
+<em>Synthetic Document Syncbase</em>.</p></dd><dt class="label">Element Information Item</dt><dd><p>Each element appearing in an XML document corresponds with an element information
 item as defined by <a href="#infoset">[XML InfoSet]</a>, §2.2.</p></dd><dt class="label">Exchange Profile</dt><dd><p>A content profile that serves a set of needs
 for content interchange.</p></dd><dt class="label">Extension</dt><dd><p>A syntactic or semantic expression or capability that is defined and
 labeled (using a extension designation) in another (public or private)
 specification.</p></dd><dt class="label">Feature</dt><dd><p>A syntactic or semantic expression or capability that is defined and
 labeled (using a feature designation) in this specification (or a
-future revision of this specification).</p></dd><dt class="label">Processor</dt><dd><p>See <em>Content Processor</em>.</p></dd><dt class="label">Processor Profile</dt><dd><p>A collection of features and extensions that must or may be implemented (supported) by
+future revision of this specification).</p></dd><dt class="label">Presentation Processor</dt><dd><p>A <em>Content Processor</em> which purpose is to layout, format, and render,
+i.e., to present, <em>Timed Text Markup Language</em> content by applying the presentation semantics
+defined in this specification.</p></dd><dt class="label">Processor</dt><dd><p>See <em>Content Processor</em>.</p></dd><dt class="label">Processor Profile</dt><dd><p>A collection of features and extensions that must or may be implemented (supported) by
 a content processor.</p></dd><dt class="label">Profile Definition Document</dt><dd><p>A document that defines a specific collection of features and extensions
 for which support is required or optional in a recipient content
 processor.</p></dd><dt class="label">Region</dt><dd><p>A logical construct that models authorial intention regarding
 desired or potential presentation processing, and which is represented as
 a rectangular area of a presentation surface into which content
-is composed and rendered during presentation processing.</p></dd><dt class="label">Reduced XML Infoset</dt><dd><p>An XML Information Set <a href="#infoset">[XML InfoSet]</a> that satisfieds the
-constraints specify by <a href="#reduced-infoset"><b>A Reduced XML Infoset</b></a>.</p></dd><dt class="label">Root Container Region</dt><dd><p>A logical region that establishes a coordinate system into which
-content regions are placed and optionally clipped.</p></dd><dt class="label">Timed Text</dt><dd><p>Textual information that is intrinsically or extrinsically
+is composed and rendered during presentation processing.</p></dd><dt class="label">Reduced XML Infoset</dt><dd><p>An XML Information Set <a href="#infoset">[XML InfoSet]</a> that satisfies the
+constraints specify by <a href="#reduced-infoset"><b>A Reduced XML Infoset</b></a>.</p></dd><dt class="label">Related Media Object</dt><dd><p>A (possibly null) media object associated with or otherwise related
+to a <em>Document Instance</em>. For example, an aggregate audio/video media
+object for which a <em>Document Instance</em> provides caption or subtitle
+information, and with which that <em>Document Instance</em> is associated.</p></dd><dt class="label">Related Media Object Region</dt><dd><p>When a non-null <em>Related Media Object</em> exists, the region in which
+a presentation processor presents this media object.</p></dd><dt class="label">Root Container Region</dt><dd><p>A logical region that establishes a coordinate system into which
+<em>Document Instance</em> content regions are placed and optionally clipped.</p></dd><dt class="label">Root Temporal Extent</dt><dd><p>
+The temporal extent (interval) defined by the temporal beginning and ending of a <em>Document Instance</em> in relationship with some external application or presentation context.
+</p></dd><dt class="label">SMPTE Time Code</dt><dd><p>A time code whose format and semantics are established by <a href="#smpte12m">[SMPTE 12M]</a>,
+which may be embedded into or otherwise associated with media content, such
+as a broadcast audio/video stream.</p></dd><dt class="label">Synthetic Document Syncbase</dt><dd><p>A document level <a href="http://www.w3.org/TR/2005/REC-SMIL2-20051213/smil-timing.html#Timing-Syncbases">syncbase</a>
+<a href="#smil21">[SMIL 2.1]</a>, § 10.7.1, synthesized or otherwise established by
+the <em>Document Processing Context</em> in accordance with the
+<em>Related Media Object</em> or other processing criteria.</p></dd><dt class="label">Synthetic SMPTE Document Syncbase</dt><dd><p>A <em>Synthetic Document Syncbase</em> constructed from <em>SMPTE Time
+Code</em> values embedded in or associated with the <em>Related Media Object</em> or
+otherwise determined by the <em>Document Processing Context</em>.</p></dd><dt class="label">Timed Text</dt><dd><p>Textual information that is intrinsically or extrinsically
 associated with timing information.</p></dd><dt class="label">Timed Text Markup Language</dt><dd><p>A content type that represents timed text media for the purpose of
 interchange among authoring systems.</p></dd><dt class="label">Timed Text Authoring System</dt><dd><p>A content authoring system capable of importing and exporting
-Timed Text Markup Language content.</p></dd></dl></div><div class="div2">
-<h3><a name="conventions" id="conventions"/>2.3 Documentation Conventions</h3><p>Within normative prose in this specification, the words
+Timed Text Markup Language content.</p></dd><dt class="label">Transformation Processor</dt><dd><p>A <em>Content Processor</em> which purpose is to transform or otherwise rewrite
+<em>Timed Text Markup Language</em> content to either <em>Timed Text Markup Language</em>
+or to another (arbitrary) content format. An example of the first is a processor that removes
+or rewrites TTML features so as to conform to a profile of TTML. An example of the latter is
+a processor that translates TTML into a completely different timed text format. Because this
+specification does not otherwise define a target profile or format for transformation processing,
+no further transformation semantics are defined by this specification.</p></dd><dt class="label">Valid Abstract Document Instance</dt><dd><p>An <em>Abstract Document Instance</em> which has been assessed for validity
+and found to be valid as defined by <a href="#doctypes"><b>4 Document Types</b></a>.</p></dd></dl></div><div class="div2">
+<h3><a id="conventions"></a>2.3 Documentation Conventions</h3><p>Within normative prose in this specification, the words
 <em>may</em>, <em>should</em>, and <em>must</em> are
 defined as follows:</p><dl class="conformance-keywords"><dt class="label">may</dt><dd><p>Conforming documents and/or TTML processors are permitted to,
 but need not behave as described. </p></dd><dt class="label">should</dt><dd><p>Conforming documents and/or TTML processors are strongly
 recommended to, but need not behave as described.</p></dd><dt class="label">must</dt><dd><p>Conforming documents and/or TTML processors are required
-to behave as described; otherwise, they are in error. </p></dd></dl><p>All normative syntactic definitions of XML representations and
-other related terms are depicted with a light orange background color
+to behave as described; otherwise, they are in error. </p></dd></dl><p>If normative specification language takes an imperative form,
+then it is to be treated as if the term <span class="strong">must</span>
+applies. Furthermore, if normative language takes a declarative form,
+and this language is governed by <span class="strong">must</span>,
+then it is also to be treated as if the term <span class="strong">must</span>
+applies.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>For example, the phrases "treat X as an error" and "consider X
+as an error" are to be read as mandatory requirements in the context of use. Similarly, if the specification
+prose is "X must apply", "X applies", or "X is mandatory", and "X" is further defined as "X is Y and Z",
+then, by transitive closure, this last declarative phrase is to be read as "Y is mandatory" and
+"Z is mandatory" in the context of use.</p></div><p>All normative syntactic definitions of XML representations and
+other related terms are depicted with a light yellow-orange background color
 and labeled as "XML Representation" or "Syntax Representation", such
-as in the following:</p><table summary="HTML Table" id="elt-syntax-example" class="syntax"><caption>XML Representation – Element Information Item: example</caption><tbody><tr><td>
+as in the following:</p><a id="elt-syntax-example"></a><table class="syntax"><caption>XML Representation – Element Information Item: example</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;example
   <span class="reqattr">count</span> = integer
@@ -661,12 +700,14 @@
 therein is given.</p><p>The allowed content of the information item is shown as a grammar
 fragment, using the Kleene operators <code>?</code>, <code>*</code>
 and <code>+</code>. Each element name therein is a hyperlink to its
-own illustration.</p><p>All content of this specification that is not explicitly marked as
+own illustration.</p><p>The term linear white-space (LWSP) is to be interpreted as a non-empty sequence of
+SPACE (U+0020), TAB (U+0009), CARRIAGE RETURN (U+000D), or LINE FEED (U+000A),
+which corresponds to production [3] <code>S</code> as defined by <a href="#xml10">[XML 1.0]</a>.</p><p>All content of this specification that is not explicitly marked as
 non-normative is considered to be normative. If a section or appendix
 header contains the expression "Non-Normative", then the entirety
 of the section or appendix is considered non-normative.</p><p>All paragraphs marked as a <span class="strong">Note</span> are considered non-normative.</p><p>Example code fragments are depicted with a light blue-green
 background color and labeled as "Example Fragment", such as in
-the following:</p><table summary="HTML Table" id="example-fragment-1" class="example"><caption>Example Fragment – Sample</caption><tbody><tr><td>
+the following:</p><a id="example-fragment-1"></a><table class="example"><caption>Example Fragment – Sample</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;tt xml:lang="" xmlns="http://www.w3.org/ns/ttml"&gt;
   &lt;head&gt;
@@ -678,62 +719,67 @@
 &lt;/tt&gt;
 </pre></div>
 </td></tr></tbody></table></div></div><div class="div1">
-<h2><a name="conformance" id="conformance"/>3 Conformance</h2><p>This section specifies the general conformance requirements for
-TTML content and processors.</p><div class="div2">
-<h3><a name="conformance-content" id="conformance-content"/>3.1 Content Conformance</h3><p>A TTML document instance conforms to this specification if the following criteria are
-satisfied:</p><ol class="enumar"><li><p>When transporting a document instance in a context in which a MIME
-Media Type <a href="#mime-media">[MIME]</a> identifies the content type of the interchanged document
-instance, then the specified media type is
-<code>application/ttml+xml</code> in conformance with <a href="#rfc3023">[XML Media Types]</a> § 7, with which an optional
+<h2><a id="conformance"></a>3 Conformance</h2><p>This section specifies the general conformance requirements for
+TTML Content and processors.</p><div class="div2">
+<h3><a id="conformance-content"></a>3.1 Content Conformance</h3><p>A TTML <em>Document Instance</em> conforms to this specification if the following criteria are
+satisfied:</p><ol class="enumar"><li><p>When transporting a <em>Document Instance</em> in a <em>Document Interchange Context</em> in which a
+Media Type <a href="#media-types">[Media Types]</a> identifies the content type of the interchanged <em>Document Instance</em>, then the specified media type is
+<code>application/ttml+xml</code> in conformance with <a href="#xml-media">[XML Media Types]</a> § 7, with which an optional
 <code>profile</code> parameter may appear, the value of which
 conforms to
 a profile designator as
 defined by
-<a href="#vocabulary-profiles"><b>5.2 Profiles</b></a>.</p></li><li><p>The document instance is or can be represented as a Reduced XML
+<a href="#vocabulary-profiles"><b>5.2 Profiles</b></a>.</p></li><li><p>The <em>Document Instance</em> is or can be represented as a Reduced XML
 Infoset as defined by <a href="#reduced-infoset"><b>A Reduced XML Infoset</b></a>.</p></li><li><p>The Reduced XML
-Infoset that corresponds to the document instance is or can
-be associated with one of the TTML Abstract
-Document Types defined by
-<a href="#doctypes"><b>4 Document Types</b></a>.</p></li><li><p>The Reduced XML Infoset that corresponds to the document instance is a
-Valid Abstract Document Instance of the associated
-Abstract Document Type.</p></li><li><p>The Reduced XML Infoset satisfies all additional mandatory syntactic and
+Infoset that corresponds to the <em>Document Instance</em> is or can
+be associated with one of the <em>Abstract Document Types</em> defined by
+<a href="#doctypes"><b>4 Document Types</b></a>.</p></li><li><p>The <em>Reduced XML Infoset</em> that corresponds to the <em>Document Instance</em> is a
+<em>Valid Abstract Document Instance</em> of the associated
+<em>Abstract Document Type</em>.</p></li><li><p>The <em>Reduced XML Infoset</em> satisfies all additional mandatory syntactic and
 semantic constraints defined by this specification. In addition, this Infoset
 should satisfy the web content accessibility guidelines specified by
 <a href="#wcag">[WCAG]</a>.</p></li></ol></div><div class="div2">
-<h3><a name="conformance-processor" id="conformance-processor"/>3.2 Processor Conformance</h3><div class="div3">
-<h4><a name="conformance-generic-processor" id="conformance-generic-processor"/>3.2.1 Generic Processor Conformance</h4><p>A TTML processor conforms to this specification if the following
+<h3><a id="conformance-processor"></a>3.2 Processor Conformance</h3><div class="div3">
+<h4><a id="conformance-generic-processor"></a>3.2.1 Generic Processor Conformance</h4><p>A TTML <em>Content Processor</em> conforms to this specification if the following
 generic processor criteria are
 satisfied:</p><ol class="enumar"><li><p>The processor provides at least one mechanism for notionally
 instantiating a Reduced XML
-Infoset representation of a conformant TTML document
-instance.</p></li><li><p>If a process does or can perform validation of a candidate TTML
-document instance, then it provides at least one mechanism to
+Infoset representation of a conformant <em>Document Instance</em>.</p></li><li><p>If a process does or can perform validation of a candidate 
+<em>Document Instance</em>, then it provides at least one mechanism to
 implicitly or explicitly associate the
-Reduced XML Infoset representation
-of a conformant TTML document instance with one of the
-TTML Abstract Document Types defined by
+<em>Reduced XML Infoset</em> representation
+of a conformant <em>Document Instance</em> with one of the
+<em>Abstract Document Types</em> defined by
 <a href="#doctypes"><b>4 Document Types</b></a>.</p></li><li><p>The processor does not <em>a priori</em> reject or abort the
-processing of a conformant TTML document instance
+processing of a conformant <em>Document Instance</em>
 unless the processor does not support some required
-(mandatory) feature specified or implied by a TTML content profile
-declared to apply to the document instance.</p></li><li><p>The processor supports all mandatory processing semantics defined by this specification.</p></li><li><p>If the processor supports some optional processing semantics defined by this specification,
-then it does so in a manner consistent with the defined semantics.</p></li></ol></div><div class="div3">
-<h4><a name="conformance-transformation-processor" id="conformance-transformation-processor"/>3.2.2 Transformation Processor Conformance</h4><p>A TTML processor is a conformant TTML transformation processor if
+(mandatory) feature specified or implied by a TTML profile
+declared to apply to the <em>Document Instance</em>.</p></li><li><p>The processor supports all mandatory processing semantics defined by this specification.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The phrase <em>mandatory semantics</em> refers to all explicit use of the conformance
+key phrases <span class="strong">must</span> and <span class="strong">must not</span> as well as any
+declarative statement that can be reasonably inferred from such key phrases. For example, these
+mandatory semantics include support for all features marked as mandatory in <a href="#feature-support"><b>D.2 Feature Support</b></a>.</p></div></li><li><p>If the processor supports some optional processing semantics defined by this specification,
+then it does so in a manner consistent with the defined semantics.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The phrase <em>optional semantics</em> refers to all explicit use of the conformance
+key phrases <span class="strong">should</span>, <span class="strong">should not</span>,
+<span class="strong">may</span>, and <span class="strong">may not</span>,
+as well as any declarative statement that can be reasonably inferred from such key phrases. For example, these
+optional semantics include support for all features marked as optional in <a href="#feature-support"><b>D.2 Feature Support</b></a>.</p></div></li></ol></div><div class="div3">
+<h4><a id="conformance-transformation-processor"></a>3.2.2 Transformation Processor Conformance</h4><p>A TTML <em>Content Processor</em> is a conformant TTML <em>Transformation Processor</em> if
 the following criteria are satisfied:</p><ol class="enumar"><li><p>The processor satisfies all requirements specified by
 <a href="#conformance-generic-processor"><b>3.2.1 Generic Processor Conformance</b></a>.</p></li><li><p>The processor supports the DFXP Transformation profile as specified
 by <a href="#profile-dfxp-transformation"><b>F.1 DFXP Transformation Profile</b></a>.</p></li></ol></div><div class="div3">
-<h4><a name="conformance-presentation-processor" id="conformance-presentation-processor"/>3.2.3 Presentation Processor Conformance</h4><ol class="enumar"><li><p>The processor satisfies all requirements specified by
+<h4><a id="conformance-presentation-processor"></a>3.2.3 Presentation Processor Conformance</h4><p>A TTML <em>Content Processor</em> is a conformant TTML <em>Presentation Processor</em> if
+the following criteria are satisfied:</p><ol class="enumar"><li><p>The processor satisfies all requirements specified by
 <a href="#conformance-generic-processor"><b>3.2.1 Generic Processor Conformance</b></a>.</p></li><li><p>The processor supports the DFXP Presentation profile as specified
 by <a href="#profile-dfxp-presentation"><b>F.2 DFXP Presentation Profile</b></a>.</p></li></ol></div></div><div class="div2">
-<h3><a name="claims" id="claims"/>3.3 Claims</h3><p>Any claim of compliance with respect to TTML content or processor
-conformance must make
+<h3><a id="claims"></a>3.3 Claims</h3><p>Any claim of compliance with respect to the conformance of a TTML <em>Document Instance</em> or
+<em>Content Processor</em> must make
 reference to an implementation compliance statement (ICS).</p><p>An implementation compliance statement must identify all mandatory
 and optional features of this specification that are satisfied by the
-content or processor implementation. In particular, the statement must
+document instance or the content processor implementation. In particular, the statement must
 identify the utilized or supported TTML vocabulary profile(s) as
 defined by <a href="#vocabulary-profiles"><b>5.2 Profiles</b></a>, and, if a subset or
 superset profile is used or supported, then what features are excluded
-or included in the subset or superset profile.</p><p>A TTML document instance for which a compliance claim is made
+or included in the subset or superset profile.</p><p>A <em>Document Instance</em> for which a compliance claim is made
 must specify
 either (1)
 a <code>ttp:profile</code> attribute on its root
@@ -744,61 +790,59 @@
 a <code>ttp:profile</code> element as a child of the
 <code>head</code> element as defined by
 <a href="#parameter-vocabulary-profile"><b>6.1.1 ttp:profile</b></a>.</p></div></div><div class="div1">
-<h2><a name="doctypes" id="doctypes"/>4 Document Types</h2><p>This section defines the following TTML Abstract Document Types:</p><ul><li><p><a href="#dfxp-content-doctype"><b>4.1 DFXP Content</b></a></p></li></ul><p>Each abstract document type consists of the following constraints:</p><ul><li><p>a non-empty collection of element types, where each element type consists of a name,
-a (possibly empty) collection of attributes, and a content specification</p></li><li><p>a non-empty collection of element types that may appear as the document element</p></li></ul><p>An Abstract Document Instance may be assessed in terms of validity,
-and is considered to be a Valid Abstract Document Instance if it
+<h2><a id="doctypes"></a>4 Document Types</h2><p>This section defines the following TTML <em>Abstract Document Types</em>:</p><ul><li><p><a href="#ttml-content-doctype"><b>4.1 TTML Content</b></a></p></li></ul><p>Each <em>Abstract Document Type</em> consists of the following constraints:</p><ul><li><p>a non-empty collection of element types, where each element type consists of a name,
+a (possibly empty) collection of attributes, and a content specification</p></li><li><p>a non-empty collection of element types that may appear as the document element</p></li></ul><p>An <em>Abstract Document Instance</em> may be assessed in terms of validity,
+and is considered to be a <em>Valid Abstract Document Instance</em> if it
 satisfies the following condition: if after</p><ol class="enumar"><li><p>pruning all element information
 items whose names are not members of the collection of element types defined
-by the associated abstract document type, then</p></li><li><p>pruning character
+by the associated <em>Abstract Document Type</em>, then</p></li><li><p>pruning character
 information item children from any remaining element in case that all
 character children of the element denote XML whitespace characters and the element's type
-is defined as empty in the associated Abstract Document Type, and then</p></li><li><p>pruning all attribute
+is defined as empty in the associated <em>Abstract Document Type</em>, and then</p></li><li><p>pruning all attribute
 information items having expanded names such that the namespace URI of the
 expanded names are not listed in <a href="#namespace-vocab-table"><b>Table 1 – Namespaces</b></a>,</p></li></ol><p>then the document element is one of the document
-element types permitted by the associated abstract document type,
+element types permitted by the associated <em>Abstract Document Type</em>,
 the descendants of the document
 element satisfy their respective element type's content
 specifications, all required attributes are present, and the declared
 value of each attribute satisfies the type declared by the
-associated abstract document type.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>While a conformant processor may not <em>a priori</em> reject a
-conformant document instance that adheres to a
-supported content profile, a given document instance may be
+associated <em>Abstract Document Type</em>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>While a conformant processor may not <em>a priori</em> reject a
+conformant <em>Document Instance</em> that adheres to a
+supported content profile, a given <em>Document Instance</em> may be
 constrained by the author or authoring tool to satisfy a more
 restrictive definition of validity.</p></div><div class="div2">
-<h3><a name="dfxp-content-doctype" id="dfxp-content-doctype"/>4.1 DFXP Content</h3><p>DFXP Content is an abstract document type of a profile of the Timed Text Markup Language intended
+<h3><a id="ttml-content-doctype"></a>4.1 TTML Content</h3><p>TTML Content is an <em>Abstract Document Type</em> of a profile of the Timed Text Markup Language intended
 to be used for interchange among distribution systems. This document type
 is defined in terms of the
 element and attribute vocabulary
-specified in <a href="#vocabulary"><b>5 Vocabulary</b></a>.</p><p>This specification defines two types of normative schemas that may be used to validate a subset of
-conformant DFXP Content document instances:</p><ul><li><p><a href="#dfxp-schema-rnc"><b>B.1 Relax NG Schema</b></a></p></li><li><p><a href="#dfxp-schema-xsd"><b>B.2 XML Schema Definition (XSD) Schema</b></a></p></li></ul><p>The (root) document element of a DFXP Content document instance must be a
-<code>tt</code> element, as defined by <a href="#document-structure-vocabulary-tt"><b>7.1.1 tt</b></a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The schemas included in this specification do not validate all syntactic constraints
-defined by this specification. In particular, performing validation with one of the above
+specified in <a href="#vocabulary"><b>5 Vocabulary</b></a>.</p><p>This specification references two types of schemas that may be used to validate a superset/subset
+of conformant TTML Content <em>Document Instances</em>:</p><ul><li><p><a href="#ttml-schema-rnc"><b>B.1 Relax NG Compact (RNC) Schema</b></a></p></li><li><p><a href="#ttml-schema-xsd"><b>B.2 XML Schema Definition (XSD) Schema</b></a></p></li></ul><p>The (root) document element of a TTML Content <em>Document Instance</em> must be a
+<code>tt</code> element, as defined by <a href="#document-structure-vocabulary-tt"><b>7.1.1 tt</b></a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The schemas referenced by this specification do not validate all syntactic constraints
+defined by this specification, and, as such, represent a superset of conformant
+TTML Content. In particular, performing validation with one of the above
 referenced schemas may result in a <em>false positive</em> indication of validity.
-However, with one exception, their
-use will not produce a <em>false negative</em> indication of validity
-when used with a compliant validating
-processor.</p><p>In exception to the above statement about false negatives,
-if the Relax NG schema included in this specification is used to validate a
-TTML Document containing elements in a foreign namespace and the <code>xml:id</code>
-attribute is used with any of those (foreign) elements,
-then an error will be reported even though such usage is permitted by this
-specification. In this case, the false negative arises due
-to a specific limitation in expressing wildcard patterns involving <code>xsd:ID</code>
-typed attributes in Relax NG schemas.
-Note that this specification defines the formal validity of a TTML Document to be
-based on an abstract document instance from which all foreign namespace elements and
-attributes have been removed. Therefore, the exceptional reporting of this false
-negative does not impact the formal assessment of TTML Document validity.</p></div></div></div><div class="div1">
-<h2><a name="vocabulary" id="vocabulary"/>5 Vocabulary</h2><p>This section defines the
-namespaces, profiles, and vocabulary (as an element an attribute
+For example, both the RNC and XSD schemas specify
+that a <code>tts:fontFamily</code> attribute must
+satisfy the <code>xs:string</code> XSD data type; however, this data type is a superset
+of the values permitted to be used with the <code>tts:fontFamily</code> attribute.</p><p>In addition, the RNC schema may produce a <em>false negative</em>
+indication of validity when using the <code>xml:id</code> attribute with an element in
+a foreign namespace, thus representing a subset of conformant TTML Content. This is
+due to a specific limitation in expressing wildcard patterns involving <code>xsd:ID</code>
+typed attributes in Relax NG schemas. Note that this specification defines the
+formal validity of a <em>Document Instance</em> to be based on an <em>Abstract Document Instance</em> from
+which all foreign namespace elements and attributes have been removed. Therefore, the
+exceptional reporting of this false negative does not impact the formal assessment
+of <em>Document Instance</em> validity.</p></div></div></div><div class="div1">
+<h2><a id="vocabulary"></a>5 Vocabulary</h2><p>This section defines the
+namespaces, profiles, and vocabulary (as an element and attribute
 catalog) of the Timed Text Markup Language (TTML) as follows:</p><ul><li><p><a href="#vocabulary-namespaces"><b>5.1 Namespaces</b></a></p></li><li><p><a href="#vocabulary-profiles"><b>5.2 Profiles</b></a></p></li><li><p><a href="#vocabulary-overview"><b>5.3 Catalog</b></a></p></li></ul><div class="div2">
-<h3><a name="vocabulary-namespaces" id="vocabulary-namespaces"/>5.1 Namespaces</h3><p>The Timed Text Markup Language (TTML) employs a number of
-namespaces for elements and certain
+<h3><a id="vocabulary-namespaces"></a>5.1 Namespaces</h3><p>The Timed Text Markup Language (TTML) employs a number of
+XML Namespaces <a href="#xmlns10">[XML Namespaces 1.0]</a> for elements and certain
 global attributes. The following table specifies this set of namespaces
 and indicates the default prefix used within this specification and the
-normative URI that denotes each namespace.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>In a specific document instance, it is not required that the default
+normative URI that denotes each namespace.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>In a specific <em>Document Instance</em>, it is not required that the default
 prefixes shown below are used. Any prefix or namespace binding that satisfies the constraints
-of XML Namespaces may be used that is associated with the specified namespace URI.</p></div><table summary="HTML Table" id="namespace-vocab-table" class="common"><caption>Table 1 – Namespaces</caption><col width="30%" span="1"/><tbody><tr><th>Name</th><th>Prefix</th><th>Value</th></tr><tr><td>TT</td><td><code>tt:</code></td><td><code>http://www.w3.org/ns/ttml</code></td></tr><tr><td>TT Parameter</td><td><code>ttp:</code></td><td><code>http://www.w3.org/ns/ttml#parameter</code></td></tr><tr><td>TT Style</td><td><code>tts:</code></td><td><code>http://www.w3.org/ns/ttml#styling</code></td></tr><tr><td>TT Metadata</td><td><code>ttm:</code></td><td><code>http://www.w3.org/ns/ttml#metadata</code></td></tr><tr><td>TT Profile</td><td><em>none</em></td><td><code>http://www.w3.org/ns/ttml/profile/</code></td></tr><tr><td>TT Feature</td><td><em>none</em></td><td><code>http://www.w3.org/ns/ttml/feature/</code></td></tr><tr><td>TT Extension</td><td><em>none</em></td><td><code>http://www.w3.org/ns/ttml/extension/</code></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>If a reference to an element type is used in this specification and the name
+of XML Namespaces <a href="#xmlns10">[XML Namespaces 1.0]</a>  may be used that is associated with the specified namespace URI.</p></div><a id="namespace-vocab-table"></a><table class="common"><caption>Table 1 – Namespaces</caption><col width="30%" span="1"><col span="1"><col span="1"><tbody><tr><th>Name</th><th>Prefix</th><th>Value</th></tr><tr><td>TT</td><td><code>tt:</code></td><td><code>http://www.w3.org/ns/ttml</code></td></tr><tr><td>TT Parameter</td><td><code>ttp:</code></td><td><code>http://www.w3.org/ns/ttml#parameter</code></td></tr><tr><td>TT Style</td><td><code>tts:</code></td><td><code>http://www.w3.org/ns/ttml#styling</code></td></tr><tr><td>TT Metadata</td><td><code>ttm:</code></td><td><code>http://www.w3.org/ns/ttml#metadata</code></td></tr><tr><td>TT Profile</td><td><em>none</em></td><td><code>http://www.w3.org/ns/ttml/profile/</code></td></tr><tr><td>TT Feature</td><td><em>none</em></td><td><code>http://www.w3.org/ns/ttml/feature/</code></td></tr><tr><td>TT Extension</td><td><em>none</em></td><td><code>http://www.w3.org/ns/ttml/extension/</code></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>If a reference to an element type is used in this specification and the name
 of the element type is not namespace qualified, then the TT Namespace applies.</p><p>For certain namespaces defined above, the default prefix
 is specified as <em>none</em> if no XML vocabulary is defined in
 the namespace by this specification (nor expected to be defined in a
@@ -808,7 +852,7 @@
 dereferencing standard profile definitions.</p></div><p>All TTML Namespaces are <a href="http://www.w3.org/2001/tag/doc/namespaceState#namespacedef"><em>mutable</em></a>
 <a href="#nsstate">[NSState]</a>; all undefined names in these namespaces are reserved for future
 standardization by the W3C.</p></div><div class="div2">
-<h3><a name="vocabulary-profiles" id="vocabulary-profiles"/>5.2 Profiles</h3><p>The Timed Text Markup Language (TTML) employs a number of
+<h3><a id="vocabulary-profiles"></a>5.2 Profiles</h3><p>The Timed Text Markup Language (TTML) employs a number of
 standard, predefined profiles of its
 vocabulary and associated semantics.
 The following table specifies this set of
@@ -817,18 +861,19 @@
 and designator for each
 predefined profile,
 and where each of these profiles is formally elaborated in
-<a href="#profiles"><b>F Profiles</b></a>.</p><table summary="HTML Table" id="profile-vocab-table" class="common"><caption>Table 2 – Profiles</caption><col width="25%" span="1"/><tbody><tr><th>Name</th><th>Designator</th></tr><tr><td>DFXP Transformation</td><td><code>http://www.w3.org/ns/ttml/profile/dfxp-transformation</code></td></tr><tr><td>DFXP Presentation</td><td><code>http://www.w3.org/ns/ttml/profile/dfxp-presentation</code></td></tr><tr><td>DFXP Full</td><td><code>http://www.w3.org/ns/ttml/profile/dfxp-full</code></td></tr></tbody></table><p/><p>A profile designator must adhere to the
+<a href="#profiles"><b>F Profiles</b></a> or in another TTWG specification.</p><a id="profile-vocab-table"></a><table class="common"><caption>Table 2 – Profiles</caption><col width="25%" span="1"><col span="1"><tbody><tr><th>Name</th><th>Designator</th></tr><tr><td>DFXP Transformation</td><td><code>http://www.w3.org/ns/ttml/profile/dfxp-transformation</code></td></tr><tr><td>DFXP Presentation</td><td><code>http://www.w3.org/ns/ttml/profile/dfxp-presentation</code></td></tr><tr><td>DFXP Full</td><td><code>http://www.w3.org/ns/ttml/profile/dfxp-full</code></td></tr><tr><td>SDP US</td><td><code>http://www.w3.org/ns/ttml/profile/sdp-us</code></td></tr></tbody></table><p></p><p>A profile designator must adhere to the
 <code>xsd:anyURI</code> data type defined by <a href="#xsd-2">[XML Schema Part 2]</a>,
 §3.2.17. If the profile designator is expressed as a relative URI,
 then it must be absolutized by using the TT Profile Namespace value as
 the base URI.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>For example, if a profile designator is expressed as
 <code>dfxp-presentation</code>, then the absolutized profile designator
 would be
-<code>http://www.w3.org/ns/ttml/profile/dfxp-presentation</code>.</p></div><p>A profile designator is not restricted to the set of designators enumerated
-in <a href="#profile-vocab-table"><b>Table 2 – Profiles</b></a>, but may be any URI that
-feasibly dereferences a TTML Profile Definition Document.</p><p>The profile of TTML that must be supported by a
-TTML content processor in order to process a document
-instance is specified either (1) by specifying a
+<code>http://www.w3.org/ns/ttml/profile/dfxp-presentation</code>.</p></div><p>All profile designators which have the TT Profile Namespace as a prefix but are otherwise not listed in
+<a href="#profile-vocab-table"><b>Table 2 – Profiles</b></a> are reserved for future standardization, and must not be appear in a conformant
+<em>Document Instance</em>. Nothwithstanding this constraint, a profile designator is not restricted to the set of designators enumerated
+in <a href="#profile-vocab-table"><b>Table 2 – Profiles</b></a>, but may be any URI that feasibly dereferences a TTML <em>Profile Definition Document</em>
+provided it does not use the TT Profile Namespace as a prefix.</p><p>The profile of TTML that must be supported by a
+TTML <em>Content Processor</em> in order to process a <em>Document Instance</em> is determined either (1) by specifying a
 <code>ttp:profile</code> attribute on the root <code>tt</code> element, as
 defined by <a href="#parameter-attribute-profile"><b>6.2.8 ttp:profile</b></a>, or (2) by
 including one or more <code>ttp:profile</code>
@@ -837,10 +882,10 @@
 descendant of the <code>tt</code> element, then the <a href="#parameter-attribute-profile"><code>ttp:profile</code></a>
 attribute should not be specified on the <code>tt</code> element. If both
 a <code>ttp:profile</code> element and a <code>ttp:profile</code>
-attribute are present (in a given document instance), then the
+attribute are present (in a given <em>Document Instance</em>), then the
 <code>ttp:profile</code> attribute must be ignored for the purpose of
 determining the declared profile requirements.</p><p>If more than one <code>ttp:profile</code> element appears in
-a TTML document instance, then all specified profiles apply
+a <em>Document Instance</em>, then all specified profiles apply
 simultaneously.  In such a case, if some feature or some extension is
 specified by one profile to be used (mandatory and enabled) and by
 another profile to be required (mandatory) or optional (voluntary),
@@ -852,19 +897,25 @@
 <a href="#parameter-attribute-profile"><code>ttp:profile</code></a>
 attribute nor
 <a href="#parameter-vocabulary-profile"><code>ttp:profile</code></a>
-element is present in a TTML document instance, and if the document
-interchange context does not specify a profile,
-then the DFXP Transformation
-profile applies.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>It is intended that the <code>ttp:profile</code> attribute be used when
+element is present in a <em>Document Instance</em>, and if the <em>Document
+Interchange Context</em> does not make an implicit or explicit
+reference to a pre-defined Content Profile or does not specify a <em>Profile Definition
+Document</em> or another equivalent set of feature designations,
+then the DFXP Transformation profile applies.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>It is not a requirement on a conformant <em>Document Instance</em> that a <em>Content Profile</em> be internally
+defined by use of a <code>ttp:profile</code> element or internally referenced by a
+<code>ttp:profile</code> attribute. More specifically, it is permitted that the <em>Document
+Interchange Context</em> determines the applicable <em>Content Profile</em> through private
+agreement, out-of-band protocol, or common use (between sender and receiver) of a profile defined
+by an external specification.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>It is intended that the <code>ttp:profile</code> attribute be used when
 the author wishes to reference one of the standard, predefined profiles of
-TTML content, and does not wish to modify (by supersetting or subsetting)
+TTML Content, and does not wish to modify (by supersetting or subsetting)
 that profile. This attribute may also be used by an author to indicate the use
 of a non-standard profile, in which case the specified profile designator expresses
-a URI that denotes an externally defined TTML Profile Definition Document.
-However, it is not required that a conformant TTML content processor be able
+a URI that denotes an externally defined <em>Profile Definition Document</em>.
+However, it is not required that a conformant TTML Content Processor be able
 to dereference such an externally specified profile definition.</p><p>In contrast, it is intended that the <code>ttp:profile</code> element be
 used when the author wishes to make use of a modified predefined profile or
-wishes to include in the document instance a non-standard profile definition
+wishes to include in the <em>Document Instance</em> a non-standard profile definition
 not based upon one of the predefined profiles.</p><p>A predefined profile is supersetted by specifying some feature or extension to
 be required (mandatory) that was either not specified in the underlying, baseline
 profile or was specified as optional (voluntary) in the baseline profile.
@@ -874,13 +925,13 @@
 is referred to as a <em>subtractive</em> profile; when modified by supersetting, the result
 is referred to as an <em>additive</em> profile.
 It is also possible to define a derived profile that is simultaneously subtractive
-and additive.</p></div><p>If a TTML document instance makes use of a feature defined by
+and additive.</p></div><p>If a <em>Document Instance</em> makes use of a feature defined by
 <a href="#feature-designations"><b>D.1 Feature Designations</b></a> and if the intended use of the
 document requires the recognition and processing of that feature, then
 the document must include a <em>required feature</em> or
 a <em>used feature</em>
 specification in one of its declared or
-referenced profiles.  If a TTML document instance makes use
+referenced profiles.  If a <em>Document Instance</em> makes use
 of an extension designatable by <a href="#extension-designations"><b>E.1 Extension Designations</b></a> and if the intended use of the document
 requires the recognition and processing of that extension, then the
 document must include a <em>required extension</em> or
@@ -899,7 +950,7 @@
 respectively.</p></div><p>An example of an author defined
 additive, derived profile of the DFXP Presentation
 profile is shown
-below in <a href="#dfxp-example-sub-profile"><b>Example Fragment – DFXP Additive Profile</b></a>.</p><table summary="HTML Table" id="dfxp-example-sub-profile" class="example"><caption>Example Fragment – DFXP Additive Profile</caption><tbody><tr><td>
+below in <a href="#ttml-example-sub-profile"><b>Example Fragment – DFXP Additive Profile</b></a>.</p><a id="ttml-example-sub-profile"></a><table class="example"><caption>Example Fragment – DFXP Additive Profile</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;tt xml:lang="" xmlns="http://www.w3.org/ns/ttml"&gt;
  &lt;head&gt;
@@ -918,17 +969,16 @@
 optional as it is defined
 in <a href="#profile-dfxp-presentation"><b>F.2 DFXP Presentation Profile</b></a>). Note also the resetting of the
 default XMLNS binding on the <code>profile</code> element to the TT Parameter Namespace.</p></div></div><div class="div2">
-<h3><a name="vocabulary-overview" id="vocabulary-overview"/>5.3 Catalog</h3><p>The vocabulary of the Timed Text Markup Language (TTML) is
+<h3><a id="vocabulary-overview"></a>5.3 Catalog</h3><p>The vocabulary of the Timed Text Markup Language (TTML) is
 defined in the following major catalogs (divisions of vocabulary):</p><ul><li><p><a href="#core-vocabulary-overview"><b>5.3.1 Core Catalog</b></a></p></li><li><p><a href="#extension-vocabulary-overview"><b>5.3.2 Extension Catalog</b></a></p></li></ul><p>The core catalog defines the baseline, core vocabulary of TTML,
-and, in particular, the vocabulary of DFXP Content. The extension catalog
+and, in particular, the vocabulary of TTML Content. The extension catalog
 serves as a placeholder for extensions to the core vocabulary defined
 by TTML.</p><div class="div3">
-<h4><a name="core-vocabulary-overview" id="core-vocabulary-overview"/>5.3.1 Core Catalog</h4><p>The core vocabulary catalog is intended to satisfy the needs of
+<h4><a id="core-vocabulary-overview"></a>5.3.1 Core Catalog</h4><p>The core vocabulary catalog is intended to satisfy the needs of
 TTML while providing a baseline vocabulary for future profiles. This vocabulary
 is divided into distinct categories, specified in detail
-in the following sections:</p><ul><li><p><a href="#parameters"><b>6 Parameters</b></a></p></li><li><p><a href="#content"><b>7 Content</b></a></p></li><li><p><a href="#styling"><b>8 Styling</b></a></p></li><li><p><a href="#layout"><b>9 Layout</b></a></p></li><li><p><a href="#timing"><b>10 Timing</b></a></p></li><li><p><a href="#animation"><b>11 Animation</b></a></p></li><li><p><a href="#metadata"><b>12 Metadata</b></a></p></li></ul><p>The core element vocabulary specified for use with a TTML document
-instance is enumerated in
-<a href="#element-vocab-table"><b>Table 3 – Element Vocabulary</b></a>.</p><table summary="HTML Table" id="element-vocab-table" class="common"><caption>Table 3 – Element Vocabulary</caption><col width="25%" span="1"/><tbody><tr><th>Module</th><th>Elements</th></tr><tr><td>
+in the following sections:</p><ul><li><p><a href="#parameters"><b>6 Parameters</b></a></p></li><li><p><a href="#content"><b>7 Content</b></a></p></li><li><p><a href="#styling"><b>8 Styling</b></a></p></li><li><p><a href="#layout"><b>9 Layout</b></a></p></li><li><p><a href="#timing"><b>10 Timing</b></a></p></li><li><p><a href="#animation"><b>11 Animation</b></a></p></li><li><p><a href="#metadata"><b>12 Metadata</b></a></p></li></ul><p>The core element vocabulary specified for use with a <em>Document Instance</em> is enumerated in
+<a href="#element-vocab-table"><b>Table 3 – Element Vocabulary</b></a>.</p><a id="element-vocab-table"></a><table class="common"><caption>Table 3 – Element Vocabulary</caption><col width="25%" span="1"><col span="1"><tbody><tr><th>Module</th><th>Elements</th></tr><tr><td>
 Animation
 </td><td>
 <a href="#animation-vocabulary-set">set</a>
@@ -976,8 +1026,8 @@
 </td><td>
 <a href="#styling-vocabulary-styling">styling</a>,
 <a href="#styling-vocabulary-style">style</a>
-</td></tr></tbody></table><p/><p>Element vocabulary groups that are used in defining content models
-for TTML element types are enumerated in <a href="#element-vocab-group-table"><b>Table 4 – Element Vocabulary Groups</b></a>.</p><table summary="HTML Table" id="element-vocab-group-table" class="common"><caption>Table 4 – Element Vocabulary Groups</caption><col width="25%" span="1"/><tbody><tr><th>Group</th><th>Elements</th></tr><tr><td>
+</td></tr></tbody></table><p></p><p>Element vocabulary groups that are used in defining content models
+for TTML element types are enumerated in <a href="#element-vocab-group-table"><b>Table 4 – Element Vocabulary Groups</b></a>.</p><a id="element-vocab-group-table"></a><table class="common"><caption>Table 4 – Element Vocabulary Groups</caption><col width="25%" span="1"><col span="1"><tbody><tr><th>Group</th><th>Elements</th></tr><tr><td>
 Animation.class
 </td><td>
 <a href="#animation-vocabulary-set">set</a>
@@ -1000,9 +1050,9 @@
 <a href="#metadata-vocabulary-copyright">ttm:copyright</a> |
 <a href="#metadata-vocabulary-desc">ttm:desc</a> |
 <a href="#metadata-vocabulary-title">ttm:title</a>
-</td></tr><tr><td>Parameters.class</td><td><a href="#parameter-vocabulary-profile">ttp:profile</a></td></tr></tbody></table><p/><p>The attribute vocabulary specified for use with the core vocabulary
+</td></tr><tr><td>Parameters.class</td><td><a href="#parameter-vocabulary-profile">ttp:profile</a></td></tr></tbody></table><p></p><p>The attribute vocabulary specified for use with the core vocabulary
 catalog is enumerated in
-<a href="#attribute-vocab-table"><b>Table 5 – Attribute Vocabulary</b></a>.</p><table summary="HTML Table" id="attribute-vocab-table" class="common"><caption>Table 5 – Attribute Vocabulary</caption><col width="25%" span="1"/><tbody><tr><th>Module</th><th>Attributes</th></tr><tr><td>
+<a href="#attribute-vocab-table"><b>Table 5 – Attribute Vocabulary</b></a>.</p><a id="attribute-vocab-table"></a><table class="common"><caption>Table 5 – Attribute Vocabulary</caption><col width="25%" span="1"><col span="1"><tbody><tr><th>Module</th><th>Attributes</th></tr><tr><td>
 Core Attributes
 </td><td>
 <a href="#content-attribute-id">xml:id</a>,
@@ -1076,31 +1126,31 @@
 the so-called <em>lowerCamelCase</em> naming convention. In some cases, this results in the
 change of a name when the name was based upon another specification
 that used a different naming convention.</p></div></div><div class="div3">
-<h4><a name="extension-vocabulary-overview" id="extension-vocabulary-overview"/>5.3.2 Extension Catalog</h4><p>The extension vocabulary catalog is intended for use by future
+<h4><a id="extension-vocabulary-overview"></a>5.3.2 Extension Catalog</h4><p>The extension vocabulary catalog is intended for use by future
 profiles of TTML, and is not further defined
-by this version of this specification.</p><p>In addition to standardized extension vocabulary, a conforming TTML
-document instance may contain arbitrary namespace qualified
+by this version of this specification.</p><p>In addition to standardized extension vocabulary, a conforming 
+<em>Document Instance</em> may contain arbitrary namespace qualified
 elements that reside in any namespace other than those namespaces
-defined for use with this specification. Furthermore, a conforming TTML
-document instance may contain arbitrary namespace qualified
+defined for use with this specification. Furthermore, a conforming 
+<em>Document Instance</em> may contain arbitrary namespace qualified
 attributes on TTML defined vocabulary where such attributes reside in
 any namespace other than those defined for use with this
 specification.</p></div></div></div><div class="div1">
-<h2><a name="parameters" id="parameters"/>6 Parameters</h2><p>This section specifies the <em>parameters</em> matter of the
+<h2><a id="parameters"></a>6 Parameters</h2><p>This section specifies the <em>parameters</em> matter of the
 core vocabulary catalog, where
 parameters are to be understood as information that is either (1)
 essential or (2) of significant importance for the purpose of
 interpreting the semantics of other types of information expressed by
-core vocabulary items or for establishing a processing context by means
-of which TTML content can be related to an external environment.</p><div class="div2">
-<h3><a name="parameter-element-vocabulary" id="parameter-element-vocabulary"/>6.1 Parameter Element Vocabulary</h3><p>The following elements, all defined in the TT Parameter
-Namespace, specify parametric information that applies to a document
-or a content processor:</p><ul><li><p><a href="#parameter-vocabulary-profile"><b>6.1.1 ttp:profile</b></a></p></li><li><p><a href="#parameter-vocabulary-features"><b>6.1.2 ttp:features</b></a></p></li><li><p><a href="#parameter-vocabulary-feature"><b>6.1.3 ttp:feature</b></a></p></li><li><p><a href="#parameter-vocabulary-extensions"><b>6.1.4 ttp:extensions</b></a></p></li><li><p><a href="#parameter-vocabulary-extension"><b>6.1.5 ttp:extension</b></a></p></li></ul><div class="div3">
-<h4><a name="parameter-vocabulary-profile" id="parameter-vocabulary-profile"/>6.1.1 ttp:profile</h4><p>The <code>ttp:profile</code> element is used to specify a collection of
+core vocabulary items or for establishing a <em>Document Processing Context</em> by means
+of which TTML Content can be related to an external environment.</p><div class="div2">
+<h3><a id="parameter-element-vocabulary"></a>6.1 Parameter Element Vocabulary</h3><p>The following elements, all defined in the TT Parameter
+Namespace, specify parametric information that applies to a <em>Document Instance</em>
+or <em>Content Processor</em>:</p><ul><li><p><a href="#parameter-vocabulary-profile"><b>6.1.1 ttp:profile</b></a></p></li><li><p><a href="#parameter-vocabulary-features"><b>6.1.2 ttp:features</b></a></p></li><li><p><a href="#parameter-vocabulary-feature"><b>6.1.3 ttp:feature</b></a></p></li><li><p><a href="#parameter-vocabulary-extensions"><b>6.1.4 ttp:extensions</b></a></p></li><li><p><a href="#parameter-vocabulary-extension"><b>6.1.5 ttp:extension</b></a></p></li></ul><div class="div3">
+<h4><a id="parameter-vocabulary-profile"></a>6.1.1 ttp:profile</h4><p>The <code>ttp:profile</code> element is used to specify a collection of
 used (mandatory and enabled), required (mandatory),
 and optional (voluntary) features and extensions that must or
-may be supported by a TTML content processor in order to process a TTML
-document that makes use (or may make use) of such features and
+may be supported by a <em>Content Processor</em> in order to process a
+<em>Document Instance</em> that makes (or may make) use of such features and
 extensions.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The difference between a <em>feature</em> and an
 <em>extension</em> is where it is defined and how it is labeled:
 if defined in this specification (or a future revision thereof) and
@@ -1109,21 +1159,20 @@
 and labeled there with an extension designation, then it is considered
 to be an extension. In general, features are expected to be defined by
 the W3C standards process, while extensions are expected to be defined by
-third parties.</p></div><p>This specification defines two distinct uses of the <code>ttp:profile</code> element:</p><ul><li><p>as a child of the <code>head</code> element within a TTML document
-instance;</p></li><li><p>as the root element of a TTML Profile Definition document
-instance;</p></li></ul><p>When a <code>tt:profile</code> element appears within a TTML document
-instance, its purpose is to express authorial intentions about which
+third parties.</p></div><p>This specification defines two distinct uses of the <code>ttp:profile</code> element:</p><ul><li><p>as a child of the <code>head</code> element within a TTML <em>Document Instance</em>;</p></li><li><p>as the root element of a TTML <em>Profile Definition Document</em>
+instance;</p></li></ul><p>When a <code>tt:profile</code> element appears within a TTML <em>Document Instance</em>,
+its purpose is to express authorial intentions about which
 features and extensions must or may be supported by a recipient
 content processor. In addition, the element indirectly expresses
 information about the set of features or extensions that are (or may
-expected to be) used by the document instance.</p><p>When a <code>tt:profile</code> element is used by a TTML
-Profile Definition document instance, it serves to publish a machine
-readable specification of a specific TTML content profile, of which
-this specification defines three such Profile Definition Documents in
+expected to be) used by the <em>Document Instance</em>.</p><p>When a <code>tt:profile</code> element is used by a TTML <em>Profile Definition Document</em> instance,
+it serves to publish a machine
+readable specification of a specific TTML profile, of which
+this specification defines three such <em>Profile Definition Documents</em> in
 <a href="#profiles"><b>F Profiles</b></a>.</p><p>The <code>ttp:profile</code> element accepts as its children zero or more
 elements in the <code>Metadata.class</code> element group, followed by
 zero or more <code>ttp:features</code> elements, followed by
-zero or more <code>ttp:extensions</code> elements.</p><table summary="HTML Table" id="elt-syntax-parameter-profile" class="syntax"><caption>XML Representation – Element Information Item: ttp:profile</caption><tbody><tr><td>
+zero or more <code>ttp:extensions</code> elements.</p><a id="elt-syntax-parameter-profile"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttp:profile</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttp:profile
   use = string
@@ -1137,9 +1186,9 @@
 §3.2.17, and, furthermore, must denote a profile designator in
 accordance with <a href="#vocabulary-profiles"><b>5.2 Profiles</b></a>. In this case,
 the profile designator must refer to (1) a standard, predefined
-TTML Profile Definition Document as defined by <a href="#profiles"><b>F Profiles</b></a>,
-or (2) a dereferenceable resource representing a valid TTML Profile Definition
-document instance. In either case, the referenced profile serves as the
+<em>Profile Definition Document</em> as defined by <a href="#profiles"><b>F Profiles</b></a>,
+or (2) a feasibly dereferenceable resource representing a valid <em>Profile Definition
+Document</em> instance. In either case, the referenced profile serves as the
 baseline profile of the specifying <code>ttp:profile</code> element.</p><p>If the <code>use</code> attribute is not specified, then the baseline
 profile of the <code>ttp:profile</code> element must be considered to be
 the empty (null) profile, i.e., a profile definition containing no
@@ -1154,20 +1203,20 @@
 entails replacing an existing feature or extension specification, if
 it already exists, or adding a new feature or extension specification,
 if it does not yet exist in the profile;</p></li></ol><p>A conformant TTML processor is not required to be able to
-dereference a TTML Profile Definition Document that is not one of the
-standard, predefined profiles defined by <a href="#profiles"><b>F Profiles</b></a>.  A
-conformant TTML processor may make use of a built-in, static
+dereference a <em>Profile Definition Document</em> that is not one of the
+standard, predefined profiles defined by <a href="#profiles"><b>F Profiles</b></a>.  Furthermore,
+a conformant TTML processor may make use of a built-in, static
 form of each standard, predefined profile so as not to require
-dereferencing a network resource.</p><p>If a TTML processor is unable to dereference a non-standard TTML
-Profile Definition Document, then it must not further process the
+dereferencing a network resource.</p><p>If a TTML processor is unable to dereference a non-standard
+<em>Profile Definition Document</em>, then it must not further process the
 document without the presence of an explicit override from an end-user
 or some implementation specific parameter traceable to an end-user or
 to a user or system configuration setting. If a TTML processor aborts
-processing of a TTML document instance due to the inability to
-reference a non-standard TTML Profile Definition Document, then some
+processing of a <em>Document Instance</em> due to the inability to
+reference a non-standard <em>Profile Definition Document</em>, then some
 end-user notification should be given unless the end-user or system
 has disabled such a notification, or if the processor does not permit
-or entail the intervention of an end-user.</p><p>The <code>ttp:profile</code> element is illustrated by the following example.</p><table summary="HTML Table" id="parameter-vocabulary-profile-example-1" class="example"><caption>Example Fragment – ttp:profile</caption><tbody><tr><td>
+or entail the intervention of an end-user.</p><p>The <code>ttp:profile</code> element is illustrated by the following example.</p><a id="parameter-vocabulary-profile-example-1"></a><table class="example"><caption>Example Fragment – ttp:profile</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttp:profile use="dfxp-presentation"&gt;
   &lt;ttp:features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
@@ -1179,10 +1228,10 @@
 baseline profile. This baseline profile is then supersetted (thus
 creating an additive derived profile) by requiring support for
 <code>#text-outline</code> feature.</p></div></div><div class="div3">
-<h4><a name="parameter-vocabulary-features" id="parameter-vocabulary-features"/>6.1.2 ttp:features</h4><p>The <code>ttp:features</code> element is a container element used to group
+<h4><a id="parameter-vocabulary-features"></a>6.1.2 ttp:features</h4><p>The <code>ttp:features</code> element is a container element used to group
 infomation about feature support requirements.</p><p>The <code>ttp:features</code> element accepts as its children zero or more
 elements in the <code>Metadata.class</code> element group, followed by
-zero or more <code>ttp:feature</code> elements.</p><table summary="HTML Table" id="elt-syntax-parameter-features" class="syntax"><caption>XML Representation – Element Information Item: ttp:features</caption><tbody><tr><td>
+zero or more <code>ttp:feature</code> elements.</p><a id="elt-syntax-parameter-features"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttp:features</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttp:features
   xml:base = string : <em>TT Feature Namespace</em>
@@ -1202,11 +1251,11 @@
 value applies, which is the TT Feature Namespace.</p><p>The <code>xml:base</code> attribute is
 used to permit the abbreviation of feature designation URIs expressed
 by child <code>ttp:feature</code> elements.</p></div><div class="div3">
-<h4><a name="parameter-vocabulary-feature" id="parameter-vocabulary-feature"/>6.1.3 ttp:feature</h4><p>The <code>ttp:feature</code> element is used to specify
+<h4><a id="parameter-vocabulary-feature"></a>6.1.3 ttp:feature</h4><p>The <code>ttp:feature</code> element is used to specify
 infomation about support requirements for a particular feature.</p><p>The children of the <code>ttp:feature</code> element must express a non-empty
 sequence of character information items that adheres to the
 <code>xsd:anyURI</code> data type defined by <a href="#xsd-2">[XML Schema Part 2]</a>,
-§3.2.17.</p><table summary="HTML Table" id="elt-syntax-parameter-feature" class="syntax"><caption>XML Representation – Element Information Item: ttp:feature</caption><tbody><tr><td>
+§3.2.17.</p><a id="elt-syntax-parameter-feature"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttp:feature</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttp:feature
   value = (optional|required|use) : required
@@ -1223,8 +1272,11 @@
 absolute URI.  In either case (original absolute URI or resulting
 absolutized URI), the URI expressed by the <code>ttp:feature</code>
 element must further adhere to the syntax of a feature designation as
-defined by <a href="#feature-designations"><b>D.1 Feature Designations</b></a>.</p><p>If
-the URI expressed by the content of the <code>ttp:feature</code> element
+defined by <a href="#feature-designations"><b>D.1 Feature Designations</b></a>, and, furthermore,
+the specific designation that appears in this URI, i.e., the portion of the feature designation
+that starts with the fragment identifier separator '#', must
+be defined by this specification or some published version thereof (that
+has achieved REC status).</p><p>If the URI expressed by the content of the <code>ttp:feature</code> element
 is a relative URI, then an <code>xml:base</code> attribute should be
 specified on the nearest ancestor <code>ttp:features</code> element.</p><p>The <code>value</code> attribute specifies whether a conforming TTML
 processor must or may implement the designated feature in order to
@@ -1232,22 +1284,25 @@
 is <code>optional</code>, then the processor need
 not implement or otherwise support the feature in order to process the
 document; if the value is <code>required</code>, then the processor
-must implement or otherwise support the feature in order to process
+must implement or otherwise support the feature, irrespective of
+whether the feature is enabled or disabled, in order to process
 the document; if the value is
 <code>use</code>, then the processor must both (1) implement or
-otherwise support the feature and (2) enable (activate) use of the
+otherwise support the feature and (2) have enabled (activated) use of the
 feature.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The default value of the <code>value</code> attribute is
 <code>required</code>, as indicated in the above element information
 item definition. Therefore, if a <code>value</code> attribute is not
 specified on a <code>ttp:feature</code> element, it is equivalent to
 specifying that support for the feature is required.</p></div><p>If the value of the <code>value</code> attribute is
-<code>required</code> or <code>use</code>,
-and if the TTML processor implementation does
-not support the feature, then it must not further process the document
+<code>required</code> or <code>use</code>
+and the TTML processor implementation does
+not support the feature, or if the <code>value</code> attribute is
+<code>use</code> and the TTML processor implementation supports but has disabled
+that feature, then it must not further process the document
 without the presence of an explicit override from an end-user or some
 implementation specific parameter traceable to an end-user or to a
 user or system configuration setting.  If a TTML processor aborts
-processing of a TTML document instance due to the specification of a
+processing of a <em>Document Instance</em> due to the specification of a
 required, but unsupported feature by this element, then some end-user
 notification should be given unless the end-user or system has
 disabled such a notification, or if the processor does not permit or
@@ -1262,7 +1317,11 @@
 presence or reference to an optional feature by a document must not be
 considered to be a violation of document validity or a barrier to
 further processing if the syntactic expression is well-formed and
-valid.</p><p>The <code>ttp:feature</code> element is illustrated by the following example.</p><table summary="HTML Table" id="parameter-vocabulary-feature-example-1" class="example"><caption>Example Fragment – ttp:feature</caption><tbody><tr><td>
+valid.</p><p>If some defined (i.e., standardized) or otherwise well known feature is not specified by
+a <code>ttp:feature</code> element in a given profile, then it must be interpreted as if the feature were specified
+with the <code>value</code> attribute equal to <code>optional</code>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>In particular, if some feature is not present in a profile definition, then
+it is not to be interpreted as meaning the use of that feature (in a <em>Document Instance</em>)
+is disallowed or otherwise prohibited.</p></div><p>The <code>ttp:feature</code> element is illustrated by the following example.</p><a id="parameter-vocabulary-feature-example-1"></a><table class="example"><caption>Example Fragment – ttp:feature</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttp:profile use="http://www.w3.org/ns/ttml/profile/dfxp-presentation"&gt;
   &lt;ttp:features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
@@ -1276,14 +1335,13 @@
 <code>ttp:feature</code> elements in order to
 superset the baseline profile (since neither
 <code>#fontStyle-italic</code> nor <code>#textDecoration-under</code>
-are required by the DFXP presentation profile).  
-</p><p>The effect of this example is to express authorial intentions that
+are required by the DFXP presentation profile).</p><p>The effect of this example is to express authorial intentions that
 italic font style and text underlining must be
 supported.</p></div></div><div class="div3">
-<h4><a name="parameter-vocabulary-extensions" id="parameter-vocabulary-extensions"/>6.1.4 ttp:extensions</h4><p>The <code>ttp:extensions</code> element is a container element used to group
+<h4><a id="parameter-vocabulary-extensions"></a>6.1.4 ttp:extensions</h4><p>The <code>ttp:extensions</code> element is a container element used to group
 infomation about extension support requirements.</p><p>The <code>ttp:extensions</code> element accepts as its children zero or more
 elements in the <code>Metadata.class</code> element group, followed by
-zero or more <code>ttp:extension</code> elements.</p><table summary="HTML Table" id="elt-syntax-parameter-extensions" class="syntax"><caption>XML Representation – Element Information Item: ttp:extensions</caption><tbody><tr><td>
+zero or more <code>ttp:extension</code> elements.</p><a id="elt-syntax-parameter-extensions"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttp:extensions</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttp:extensions
   xml:base = string : <em>TT Extension Namespace</em>
@@ -1303,11 +1361,11 @@
 value applies, which is the TT Extension Namespace.</p><p>The <code>xml:base</code> attribute is
 used to permit the abbreviation of feature designation URIs expressed
 by child <code>ttp:extension</code> elements.</p></div><div class="div3">
-<h4><a name="parameter-vocabulary-extension" id="parameter-vocabulary-extension"/>6.1.5 ttp:extension</h4><p>The <code>ttp:extension</code> element is used to specify
+<h4><a id="parameter-vocabulary-extension"></a>6.1.5 ttp:extension</h4><p>The <code>ttp:extension</code> element is used to specify
 infomation about support requirements for a particular extension.</p><p>The children of the <code>ttp:extension</code> element must express a non-empty
 sequence of character information items that adheres to the
 <code>xsd:anyURI</code> data type defined by <a href="#xsd-2">[XML Schema Part 2]</a>,
-§3.2.17.</p><table summary="HTML Table" id="elt-syntax-parameter-extension" class="syntax"><caption>XML Representation – Element Information Item: ttp:extension</caption><tbody><tr><td>
+§3.2.17.</p><a id="elt-syntax-parameter-extension"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttp:extension</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttp:extension
   value = (optional|required|use) : required
@@ -1342,13 +1400,15 @@
 item definition. Therefore, if a <code>value</code> attribute is not
 specified on a <code>ttp:extension</code> element, it is equivalent to
 specifying that support for the extension is required.</p></div><p>If the value of the <code>value</code> attribute is
-<code>required</code> or <code>use</code>,
-and if the TTML processor implementation does not support the
-extension, then it must not further process the document without the
+<code>required</code> or <code>use</code>
+and the TTML processor implementation does
+not support the extension, or if the <code>value</code> attribute is
+<code>use</code> and the TTML processor implementation supports but has disabled
+that extension, then it must not further process the document without the
 presence of an explicit override from an end-user or some
 implementation specific parameter traceable to an end-user or to a
 user or system configuration setting.  If a TTML processor aborts
-processing of a TTML document instance due to the specification of a
+processing of a <em>Document Instance</em> due to the specification of a
 required, but unsupported extension by this element, then some
 end-user notification should be given unless the end-user or system
 has disabled such a notification, or if the processor does not permit
@@ -1363,10 +1423,14 @@
 presence or reference to an optional extension by a document must not be
 considered to be a violation of document validity or a barrier to
 further processing if the syntactic expression is well-formed and
-valid.</p><p>The <code>ttp:extension</code> element is illustrated by the following example.</p><table summary="HTML Table" id="parameter-vocabulary-extension-example-1" class="example"><caption>Example Fragment – ttp:extension</caption><tbody><tr><td>
+valid.</p><p>If some well known extension is not specified by
+a <code>ttp:extension</code> element in a given profile, then it must be interpreted as if the extension were specified
+with the <code>value</code> attribute equal to <code>optional</code>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>In particular, if some extension is not present in a profile definition, then
+it is not to be interpreted as meaning the use of that extension (in a <em>Document Instance</em>)
+is disallowed or otherwise prohibited.</p></div><p>The <code>ttp:extension</code> element is illustrated by the following example.</p><a id="parameter-vocabulary-extension-example-1"></a><table class="example"><caption>Example Fragment – ttp:extension</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttp:profile use="http://www.w3.org/ns/ttml/profile/dfxp-transformation"&gt;
-  &lt;ttp:extensions xml:base="http://foo.bar.example.org/ttaf1/extension/"&gt;
+  &lt;ttp:extensions xml:base="http://example.org/ttml/extension/"&gt;
     <span class="strong">&lt;ttp:extension value="use"&gt;#prefilter-by-language&lt;/ttp:extension&gt;</span>
   &lt;/ttp:extensions&gt;
 &lt;/ttp:profile&gt;
@@ -1376,13 +1440,14 @@
 specifying that support and use is required for a private extension
 defined in a third party namespace.</p><p>The effect of this example is to express authorial intentions that
 a recipient processor must support the DFXP transformation profile and
-must also support and use an extension defined by a third party.</p></div></div></div><div class="div2">
-<h3><a name="parameter-attribute-vocabulary" id="parameter-attribute-vocabulary"/>6.2 Parameter Attribute Vocabulary</h3><p>The following attributes are defined in the TT Parameter Namespace.</p><ul><li><p><a href="#parameter-attribute-cellResolution"><b>6.2.1 ttp:cellResolution</b></a></p></li><li><p><a href="#parameter-attribute-clockMode"><b>6.2.2 ttp:clockMode</b></a></p></li><li><p><a href="#parameter-attribute-dropMode"><b>6.2.3 ttp:dropMode</b></a></p></li><li><p><a href="#parameter-attribute-frameRate"><b>6.2.4 ttp:frameRate</b></a></p></li><li><p><a href="#parameter-attribute-frameRateMultiplier"><b>6.2.5 ttp:frameRateMultiplier</b></a></p></li><li><p><a href="#parameter-attribute-markerMode"><b>6.2.6 ttp:markerMode</b></a></p></li><li><p><a href="#parameter-attribute-pixelAspectRatio"><b>6.2.7 ttp:pixelAspectRatio</b></a></p></li><li><p><a href="#parameter-attribute-profile"><b>6.2.8 ttp:profile</b></a></p></li><li><p><a href="#parameter-attribute-subFrameRate"><b>6.2.9 ttp:subFrameRate</b></a></p></li><li><p><a href="#parameter-attribute-tickRate"><b>6.2.10 ttp:tickRate</b></a></p></li><li><p><a href="#parameter-attribute-timeBase"><b>6.2.11 ttp:timeBase</b></a></p></li></ul><p>Unless explicitly stated otherwise, linear white-space (LWSP) may
-appear between tokens of a value of a TT Parameter.</p><div class="div3">
-<h4><a name="parameter-attribute-cellResolution" id="parameter-attribute-cellResolution"/>6.2.1 ttp:cellResolution</h4><p>The <code>ttp:cellResolution</code> attribute may be used by an author
-to express the number of horizontal and vertical cells into which the root container region
+must also support and enable an extension defined by a third party.</p></div></div></div><div class="div2">
+<h3><a id="parameter-attribute-vocabulary"></a>6.2 Parameter Attribute Vocabulary</h3><p>The following attributes are defined in the TT Parameter Namespace.</p><ul><li><p><a href="#parameter-attribute-cellResolution"><b>6.2.1 ttp:cellResolution</b></a></p></li><li><p><a href="#parameter-attribute-clockMode"><b>6.2.2 ttp:clockMode</b></a></p></li><li><p><a href="#parameter-attribute-dropMode"><b>6.2.3 ttp:dropMode</b></a></p></li><li><p><a href="#parameter-attribute-frameRate"><b>6.2.4 ttp:frameRate</b></a></p></li><li><p><a href="#parameter-attribute-frameRateMultiplier"><b>6.2.5 ttp:frameRateMultiplier</b></a></p></li><li><p><a href="#parameter-attribute-markerMode"><b>6.2.6 ttp:markerMode</b></a></p></li><li><p><a href="#parameter-attribute-pixelAspectRatio"><b>6.2.7 ttp:pixelAspectRatio</b></a></p></li><li><p><a href="#parameter-attribute-profile"><b>6.2.8 ttp:profile</b></a></p></li><li><p><a href="#parameter-attribute-subFrameRate"><b>6.2.9 ttp:subFrameRate</b></a></p></li><li><p><a href="#parameter-attribute-tickRate"><b>6.2.10 ttp:tickRate</b></a></p></li><li><p><a href="#parameter-attribute-timeBase"><b>6.2.11 ttp:timeBase</b></a></p></li></ul><p>Unless explicitly stated otherwise, linear white-space (LWSP) must
+appear between adjacent non-terminal components of a TT Parameter value
+unless some other delimiter is permitted and used.</p><div class="div3">
+<h4><a id="parameter-attribute-cellResolution"></a>6.2.1 ttp:cellResolution</h4><p>The <code>ttp:cellResolution</code> attribute may be used by an author
+to express the number of horizontal and vertical cells into which the <em>Root Container Region</em>
 area is divided for the purpose of expressing presentation semantics in terms of
-a uniform grid.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><table summary="HTML Table" id="parameter-attribute-cellResolution-syntax" class="syntax"><caption>Syntax Representation – ttp:cellResolution</caption><tbody><tr><td>
+a uniform grid.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-cellResolution-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:cellResolution</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:cellResolution
   : columns rows                            // <em>columns</em> != 0; <em>rows</em> != 0
@@ -1399,11 +1464,16 @@
 glyph areas is
 coordinated with this grid. Such alignment is possible, but
 requires the use of a monospaced font and a font size whose EM square exactly
-matches the cell size.</p></div></div><div class="div3">
-<h4><a name="parameter-attribute-clockMode" id="parameter-attribute-clockMode"/>6.2.2 ttp:clockMode</h4><p>The <code>ttp:clockMode</code> attribute is used to specify the
+matches the cell size.</p></div><p>Except where indicated otherwise, when a <a href="#style-value-length">&lt;length&gt;</a> expressed in
+cells denotes a dimension parallel to the inline or block progression dimension,
+the cell's dimension in the inline or block progression dimension applies, respectively.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>For example, if padding (on all four edges) is specified as 0.1c, the cell resolution
+is 20 by 10, and the extent of the <em>Root Container Region</em> is 640 by 480, then, assuming top to bottom,
+left to right writing mode, the start and end padding will be (640 / 20) * 0.1 pixels and the
+before and after padding will be (480 / 10) * 0.1 pixels.</p></div></div><div class="div3">
+<h4><a id="parameter-attribute-clockMode"></a>6.2.2 ttp:clockMode</h4><p>The <code>ttp:clockMode</code> attribute is used to specify the
 interpretation of time expressions as real-time time coordinates when
 operating with time base of <code>clock</code> as defined by <a href="#parameter-attribute-timeBase"><b>6.2.11 ttp:timeBase</b></a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>See <a href="#timing-time-value-expressions"><b>10.3 Time Value Expressions</b></a> for the
-specification of time expression syntax.</p></div><p>If specified, the value of this attribute must adhere to the following syntax:</p><table summary="HTML Table" id="parameter-attribute-clockMode-syntax" class="syntax"><caption>Syntax Representation – ttp:clockMode</caption><tbody><tr><td>
+specification of time expression syntax and semantics.</p></div><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-clockMode-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:clockMode</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:clockMode
   : "local"
@@ -1429,11 +1499,11 @@
 tolerance of TAI.</p></div><p>If not specified, the value of this parameter must be considered
 to be <code>utc</code>.</p><p>A <code>ttp:clockMode</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p></div><div class="div3">
-<h4><a name="parameter-attribute-dropMode" id="parameter-attribute-dropMode"/>6.2.3 ttp:dropMode</h4><p>The <code>ttp:dropMode</code> attribute is used to specify
+<h4><a id="parameter-attribute-dropMode"></a>6.2.3 ttp:dropMode</h4><p>The <code>ttp:dropMode</code> attribute is used to specify
 constraints on the interpretation and use of frame counts
 that correspond with <a href="#smpte12m">[SMPTE 12M]</a> time coordinates when operating
 with time base of <code>smpte</code> as defined by
-<a href="#parameter-attribute-timeBase"><b>6.2.11 ttp:timeBase</b></a>.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><table summary="HTML Table" id="parameter-attribute-dropMode-syntax" class="syntax"><caption>Syntax Representation – ttp:dropMode</caption><tbody><tr><td>
+<a href="#parameter-attribute-timeBase"><b>6.2.11 ttp:timeBase</b></a>.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-dropMode-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:dropMode</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:dropMode
   : "dropNTSC"
@@ -1481,33 +1551,35 @@
 in frame count occurs between consecutive frames as shown in the
 following sequence of time expressions: <code>01:09:59:28</code>,
 <code>01:09:59:29</code>, <code>01:10:00:04</code>,
-<code>01:10:00:04</code>.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>The <code>dropPAL</code> mode is also known as the
+<code>01:10:00:05</code>.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>The <code>dropPAL</code> mode is also known as the
 <em>M/PAL</em> or <em>PAL (M)</em> drop-frame
 code, which uses PAL modulation with the NTSC frame rate of ~29.97
 frames/second. The M/PAL system is used primarily in Brazil.</p></div><p>If not specified, then <code>nonDrop</code> must be assumed to apply.</p><p>A <code>ttp:dropMode</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p></div><div class="div3">
-<h4><a name="parameter-attribute-frameRate" id="parameter-attribute-frameRate"/>6.2.4 ttp:frameRate</h4><p>The <code>ttp:frameRate</code> attribute is used to specify the frame rate of a related
-media object or the intrinsic frame rate of a document instance in case it is intended
-to function as an independent media object.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><table summary="HTML Table" id="parameter-attribute-frameRate-syntax" class="syntax"><caption>Syntax Representation – ttp:frameRate</caption><tbody><tr><td>
+<h4><a id="parameter-attribute-frameRate"></a>6.2.4 ttp:frameRate</h4><p>The <code>ttp:frameRate</code> attribute is used to specify the frame rate of a related
+media object or the intrinsic frame rate of a <em>Document Instance</em> in case it is intended
+to function as an independent media object.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-frameRate-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:frameRate</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:frameRate
   : <a href="#style-value-digit">&lt;digit&gt;</a>+                                // <em>value</em> &gt; 0
 </pre></div>
-</td></tr></tbody></table><p>The frame rate that applies to a document instance is used to
+</td></tr></tbody></table><p>The frame rate that applies to a <em>Document Instance</em> is used to
 interpret time expressions that are expressed in <em>frames</em>
-as defined by <a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a>.</p><p>A frame is interpreted as a division of a second of media
+as defined by <a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a>.</p><p>If the <code>media</code> time base applies and the effective frame rate is
+integral, then a frame is interpreted as a division of a second of media
 time, such that if the frame rate is specified as <em>F</em>, then
 a second of media time is divided into <em>F</em> intervals of
 equal duration, where each interval is labeled as frame <em>f</em>,
-with <em>f</em> ∈ [0…<em>F−1</em>].</p><p>If not specified, the frame rate must be considered to be equal to some
+with <em>f</em> ∈ [0…<em>F−1</em>].</p><div class="note"><p class="prefix"><b>Note:</b></p><p>See <a href="#time-expression-semantics-media"><b>N.2 Media Time Base</b></a> for further details
+on the interpretation of time expressions for the <code>media</code> time base.</p></div><p>If not specified, the frame rate must be considered to be equal to some
 application defined frame rate, or if no application defined frame rate applies,
 then thirty (30) frames per second. If specified, then the frame rate must
 be greater than zero (0).</p><p>A <code>ttp:frameRate</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p></div><div class="div3">
-<h4><a name="parameter-attribute-frameRateMultiplier" id="parameter-attribute-frameRateMultiplier"/>6.2.5 ttp:frameRateMultiplier</h4><p>The <code>ttp:frameRateMultiplier</code> attribute is used to
+<h4><a id="parameter-attribute-frameRateMultiplier"></a>6.2.5 ttp:frameRateMultiplier</h4><p>The <code>ttp:frameRateMultiplier</code> attribute is used to
 specify a multiplier to be applied to the frame rate specified by a
 <code>ttp:frameRate</code> attribute in order to compute the effective
-frame rate.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><table summary="HTML Table" id="parameter-attribute-frameRateMultiplier-syntax" class="syntax"><caption>Syntax Representation – ttp:frameRateMultiplier</caption><tbody><tr><td>
+frame rate.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-frameRateMultiplier-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:frameRateMultiplier</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:frameRateMultiplier
   : numerator denominator                   // <em>numerator</em> != 0; <em>denominator</em> != 0
@@ -1527,11 +1599,11 @@
 second. Other frame rate multipliers apply to different regions of
 usage and video format standards.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>Except in the case of PAL/M, the frame rate multiplier used for synchronizing with PAL
 formatted video objects at 25 frames per second is nominally 1:1.</p></div></div><div class="div3">
-<h4><a name="parameter-attribute-markerMode" id="parameter-attribute-markerMode"/>6.2.6 ttp:markerMode</h4><p>The <code>ttp:markerMode</code> attribute is used to specify
+<h4><a id="parameter-attribute-markerMode"></a>6.2.6 ttp:markerMode</h4><p>The <code>ttp:markerMode</code> attribute is used to specify
 constraints on the interpretation and use of time expressions
 that correspond with <a href="#smpte12m">[SMPTE 12M]</a> time coordinates when operating
 with time base of <code>smpte</code> as defined by
-<a href="#parameter-attribute-timeBase"><b>6.2.11 ttp:timeBase</b></a>.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><table summary="HTML Table" id="parameter-attribute-markerMode-syntax" class="syntax"><caption>Syntax Representation – ttp:markerMode</caption><tbody><tr><td>
+<a href="#parameter-attribute-timeBase"><b>6.2.11 ttp:timeBase</b></a>.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-markerMode-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:markerMode</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:markerMode
   : "continuous"
@@ -1543,16 +1615,45 @@
 may be assumed to be linear and either monotonically increasing or
 decreasing; however, if <code>discontinuous</code>, then any assumption
 must not be made regarding linearity or monotonicity of time coordinates.</p><p>If not specified, the value of this parameter must be considered
-to be <code>continuous</code>.</p><p>A <code>ttp:markerMode</code> attribute is considered to be significant only
-when specified on the <code>tt</code> element.</p><p>If a value of <code>discontinuous</code> applies, then time
-expressions must not be converted to either media time or real time
+to be <code>discontinuous</code>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The default value for this parameter was originally specified
+(in <a href="http://www.w3.org/TR/2010/REC-ttaf1-dfxp-20101118/">TTML 1.0 First Edition</a>)
+as <code>continuous</code>; however, further evaluation of the state of the industry indicates this
+choice was incorrect, and that the most common default is <code>discontinuous</code>.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>Due to lack of industry consensus on the utility and interpretation of the
+<code>continuous</code> marker mode, authors are advised to avoid its use. Furthermore, the
+<code>ttp:markerMode</code> is being considered for deprecation in the next revision of this
+specification.</p></div><p>A <code>ttp:markerMode</code> attribute is considered to be significant only
+when specified on the <code>tt</code> element.</p><p>If a value of <code>continuous</code> applies, then time
+expressions may be converted to real time
+coordinates by taking into account the computed frame rate
+and drop mode as expressed by the <code>ttp:dropMode</code> parameter.
+In this case, the <em>Content Processor</em> must create and maintain a
+<em>Synthetic SMPTE Document Syncbase</em> within which these time
+expressions are interpreted as further described in
+<a href="#timing-time-intervals"><b>10.4 Time Intervals</b></a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>When operating with <code>smpte</code> time base and
+<code>continuous</code> marker mode, there is an implied time coordinate
+space, the <em>Synthetic SMPTE Document Syncbase</em>,
+defined by the monotonically increasing (or decreasing) 
+<a href="#smpte12m">[SMPTE 12M]</a> time coordinates, while taking into account
+the computed frame rate and drop mode. All time expressions are interpreted
+in relationship to this time coordinate space based upon
+<em>SMPTE Time Code</em> synchronization events (markers),
+where the <em>Document Processing Context</em>  emits these events with implied constraints
+regarding time coordinate monoticity and resynchronization in
+the presence of dropped frames.</p><p>Use of <code>continuous</code> marker mode with the <code>smpte</code>
+time base is different from using the <code>media</code> time base
+because (1) the semantics of the <code>ttp:dropMode</code> parameter
+apply to the former, but not the latter, and (2) <a href="#smpte12m">[SMPTE 12M]</a>
+time coordinates may be applied monotonically to media which has been
+subjected to dilation in time, constriction in time, or reversal in
+time.</p></div><p>If a value of <code>discontinuous</code> applies, then time
+expressions must not be converted to real time
 coordinates, arithmetical operators (addition, multiplication) are not
-defined on time expressions, and, consequently, any expression of a
-duration must be considered to be invalid.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>When operating with <code>smpte</code> time base and
+defined on time expressions, and, consequently, any (well-formed)
+expression of a duration must be considered to be invalid.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>When operating with <code>smpte</code> time base and
 <code>discontinuous</code> marker mode, there is no effective time coordinate
 space; rather, all time expressions are interpreted as labeled
-synchronization events (markers), where some external synchronization
-context emits these events, which, when they correspond with time
+synchronization events (markers), where the <em>Document Processing Context</em>
+emits these events, which, when they correspond with time
 expressions that denote the same label, cause a temporal interval to
 begin or end accordingly.</p><p>An additional side-effect of operating in <code>discontinuous</code>
 mode is that time expressions of children have no necessary
@@ -1570,9 +1671,9 @@
 example, two consecutive frames labeled as <code>10:00:00:00</code>
 and <code>10:00:01:00</code>.
 </p></div></div><div class="div3">
-<h4><a name="parameter-attribute-pixelAspectRatio" id="parameter-attribute-pixelAspectRatio"/>6.2.7 ttp:pixelAspectRatio</h4><p>The <code>ttp:pixelAspectRatio</code> attribute may be used by a content author
+<h4><a id="parameter-attribute-pixelAspectRatio"></a>6.2.7 ttp:pixelAspectRatio</h4><p>The <code>ttp:pixelAspectRatio</code> attribute may be used by a content author
 to express the aspect ratio of non-square pixels in the production of content that
-makes use of pixel coordinates.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><table summary="HTML Table" id="parameter-attribute-pixelAspectRatio-syntax" class="syntax"><caption>Syntax Representation – ttp:pixelAspectRatio</caption><tbody><tr><td>
+makes use of pixel coordinates.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-pixelAspectRatio-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:pixelAspectRatio</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:pixelAspectRatio
   : width height                            // <em>width</em> != 0; <em>height</em> != 0
@@ -1585,46 +1686,50 @@
 when specified on the <code>tt</code> element.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>This parameter may be used by a content transcoder or translator in
 order to convert pixel measurements between different pixel aspect
 ratios while still maintaining authorial layout intentions.</p></div></div><div class="div3">
-<h4><a name="parameter-attribute-profile" id="parameter-attribute-profile"/>6.2.8 ttp:profile</h4><p>The <code>ttp:profile</code> attribute may be used by a content author
+<h4><a id="parameter-attribute-profile"></a>6.2.8 ttp:profile</h4><p>The <code>ttp:profile</code> attribute may be used by a content author
 to express the profile of the Timed Text Markup Language (TTML) used
-in a document instance.</p><p>If specified, the value of this attribute must adhere to the
+in a <em>Document Instance</em>.</p><p>If specified, the value of this attribute must adhere to the
 <code>xsd:anyURI</code> data type defined by <a href="#xsd-2">[XML Schema Part 2]</a>,
 §3.2.17, and, further, must specify a
 profile designator in accordance with
 <a href="#vocabulary-profiles"><b>5.2 Profiles</b></a>.</p><p>A <code>ttp:profile</code>
 attribute is considered to be significant only when specified on the
 <code>tt</code> element.</p></div><div class="div3">
-<h4><a name="parameter-attribute-subFrameRate" id="parameter-attribute-subFrameRate"/>6.2.9 ttp:subFrameRate</h4><p>The <code>ttp:subFrameRate</code> attribute is used to specify the sub-frame rate of a related
-media object or the intrinsic sub-frame rate of a document instance in case it is intended
-to function as an independent media object.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><table summary="HTML Table" id="parameter-attribute-subFrameRate-syntax" class="syntax"><caption>Syntax Representation – ttp:subFrameRate</caption><tbody><tr><td>
+<h4><a id="parameter-attribute-subFrameRate"></a>6.2.9 ttp:subFrameRate</h4><p>The <code>ttp:subFrameRate</code> attribute is used to specify the sub-frame rate of a related
+media object or the intrinsic sub-frame rate of a <em>Document Instance</em> in case it is intended
+to function as an independent media object.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-subFrameRate-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:subFrameRate</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:subFrameRate
   : <a href="#style-value-digit">&lt;digit&gt;</a>+                                // <em>value</em> &gt; 0
 </pre></div>
-</td></tr></tbody></table><p>The sub-frame rate that applies to a document instance is used to
+</td></tr></tbody></table><p>The sub-frame rate that applies to a <em>Document Instance</em> is used to
 interpret time expressions that are expressed in <em>sub-frames</em>
-as defined by <a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a>.</p><p>A sub-frame is interpreted as a division of a frame of media
+as defined by <a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a>.</p><p>If the <code>media</code> time base applies and the effective frame rate is
+integral, a sub-frame is interpreted as a division of a frame of media
 time, such that if the sub-frame rate is specified as <em>S</em>, then
 a frame of media time is divided into <em>S</em> intervals of
 equal duration, where each interval is labeled as sub-frame <em>s</em>,
-with <em>s</em> ∈ [0…<em>S−1</em>].</p><p>If not specified, the sub-frame rate must be considered to be
+with <em>s</em> ∈ [0…<em>S−1</em>].</p><div class="note"><p class="prefix"><b>Note:</b></p><p>See <a href="#time-expression-semantics-media"><b>N.2 Media Time Base</b></a> for further details
+on the interpretation of time expressions for the <code>media</code> time base.</p></div><p>If not specified, the sub-frame rate must be considered to be
 equal to one (1). If specified, then the sub-frame rate must be greater than zero (0).</p><p>A <code>ttp:subFrameRate</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The sub-frame is sometimes referred to as a <em>field</em> in
 the context of synchronization with an interlaced video media object.</p></div></div><div class="div3">
-<h4><a name="parameter-attribute-tickRate" id="parameter-attribute-tickRate"/>6.2.10 ttp:tickRate</h4><p>The <code>ttp:tickRate</code> attribute is used to specify the tick rate of a related
-media object or the intrinsic tick rate of content of a document instance in case it is intended
-to function as an independent media object.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><table summary="HTML Table" id="parameter-attribute-tickRate-syntax" class="syntax"><caption>Syntax Representation – ttp:tickRate</caption><tbody><tr><td>
+<h4><a id="parameter-attribute-tickRate"></a>6.2.10 ttp:tickRate</h4><p>The <code>ttp:tickRate</code> attribute is used to specify the tick rate of a related
+media object or the intrinsic tick rate of content of a <em>Document Instance</em> in case it is intended
+to function as an independent media object.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-tickRate-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:tickRate</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:tickRate
   : <a href="#style-value-digit">&lt;digit&gt;</a>+                                // <em>value</em> &gt; 0
 </pre></div>
-</td></tr></tbody></table><p>The tick rate that applies to a document instance is used to
+</td></tr></tbody></table><p>The tick rate that applies to a <em>Document Instance</em> is used to
 interpret time expressions that are expressed in <em>ticks</em> by
-using the <code>t</code> metric as defined by <a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a>.</p><p>A tick is interpreted as an integral division of a second of media
+using the <code>t</code> metric as defined by <a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a>.</p><p>If the <code>media</code> time base applies,
+a tick is interpreted as an integral division of a second of media
 time, such that if the tick rate is specified as <em>T</em>, then
 a second of media time is divided into <em>T</em> intervals of
 equal duration, where each interval is labeled as tick <em>t</em>,
-with <em>t</em> ∈ [0…<em>T−1</em>].</p><p>If not specified, then if a frame rate is specified, the tick rate
+with <em>t</em> ∈ [0…<em>T−1</em>].</p><div class="note"><p class="prefix"><b>Note:</b></p><p>See <a href="#time-expression-semantics-media"><b>N.2 Media Time Base</b></a> for further details
+on the interpretation of time expressions for the <code>media</code> time base.</p></div><p>If not specified, then if a frame rate is specified, the tick rate
 must be considered to be the effective frame rate multiplied by the
 sub-frame rate (i.e., ticks are interpreted as sub-frames); or, if no
 frame rate is specified, the tick rate must be considered to be one (1)
@@ -1634,9 +1739,9 @@
 use of fixed point arithmetic rather than fractional (and potentially
 inexact) expressions of seconds.</p></div><p>A <code>ttp:tickRate</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p></div><div class="div3">
-<h4><a name="parameter-attribute-timeBase" id="parameter-attribute-timeBase"/>6.2.11 ttp:timeBase</h4><p>The <code>ttp:timeBase</code> attribute is used to specify the
+<h4><a id="parameter-attribute-timeBase"></a>6.2.11 ttp:timeBase</h4><p>The <code>ttp:timeBase</code> attribute is used to specify the
 temporal coordinate system by means of which time expressions are
-interpreted in a document instance.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><table summary="HTML Table" id="parameter-attribute-timeBase-syntax" class="syntax"><caption>Syntax Representation – ttp:timeBase</caption><tbody><tr><td>
+interpreted in a <em>Document Instance</em>.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-timeBase-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:timeBase</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:timeBase
   : "media"
@@ -1646,44 +1751,46 @@
 </td></tr></tbody></table><p>If the time base is designated as <code>media</code>, then a time
 expression denotes a coordinate in some media object's time line,
 where the media object may be an external media object with which the
-content of a document instance is to be synchronized, or it may
-be the content of a document instance itself in a case where
+content of a <em>Document Instance</em> is to be synchronized, or it may
+be the content of a <em>Document Instance</em> itself in a case where
 the timed text content is intended to establish an independent time
 line.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>When using a media time base, if that time base is paused or
-scaled positively or negatively, then it is expected that the
+scaled positively or negatively, i.e., the media play rate is
+not unity, then it is expected that the
 presentation of associated Timed Text content will be similarly
 paused, accelerated, or decelerated, respectively. The means for
 controlling an external
 media time base is outside the scope of this specification.</p></div><p>If the time base is designated as <code>smpte</code>,
 then a time expression denotes a <a href="#smpte12m">[SMPTE 12M]</a> time
-coordinate with which the content of a document instance is to
+coordinate with which the content of a <em>Document Instance</em> is to
 be synchronized.  In this case, the value of the <code>ttp:markerMode</code> 
-and <code>ttp:dropMode</code> parameters apply, as defined by <a href="#parameter-attribute-markerMode"><b>6.2.6 ttp:markerMode</b></a> and <a href="#parameter-attribute-dropMode"><b>6.2.3 ttp:dropMode</b></a>, respectively.</p><p>If the time base is designated as <code>clock</code>, then the time
+and <code>ttp:dropMode</code> parameters apply, as defined by <a href="#parameter-attribute-markerMode"><b>6.2.6 ttp:markerMode</b></a> and <a href="#parameter-attribute-dropMode"><b>6.2.3 ttp:dropMode</b></a>, respectively.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>When the time base is designated as <code>smpte</code>,
+every time expression denotes a media marker value akin to that
+defined by <a href="#smil21">[SMIL 2.1]</a>, § 10.4.1, except instead
+of using an opaque marker name, a structured <a href="#smpte12m">[SMPTE 12M]</a>
+time coordinate serves as the marker name.</p></div><p>If the time base is designated as <code>clock</code>, then the time
 expression denotes a coordinate in some real-world time line as
 established by some real-time clock, such as the local wall-clock time
 or UTC (Coordinated Universal Time) or GPS (Global Positioning System)
 time lines.</p><p>If not specified, the default time base must be considered to be
 <code>media</code>.</p><p>A <code>ttp:timeBase</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p><p>When operating with either <code>media</code> or <code>smpte</code>
-time bases, a diachronic presentation of a document instance may
+time bases, a diachronic presentation of a <em>Document Instance</em> may
 be subject to transformations of the controlling time line, such as
 temporal reversal, dilation (expansion), or constriction
 (compression); however, when operating with the <code>clock</code>
 time base, no transformations are permitted, and diachronic
 presentation proceeds on a linear, monotonically increasing time line
 based on the passage of real time.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>Due to there being only one time base parameter that applies to a
-given document instance, the interpretation of time expressions
-is uniform throughout the document instance.</p></div><p>When operating with the <code>clock</code> time base,
-the expression <em>media time</em> as used in this specification is
-to be interpreted as the real-time clock selected by
-<a href="#parameter-attribute-clockMode"><b>6.2.2 ttp:clockMode</b></a>.</p></div></div></div><div class="div1">
-<h2><a name="content" id="content"/>7 Content</h2><p>This section specifies the <em>content</em> matter of the core
+given <em>Document Instance</em>, the interpretation of time expressions
+is uniform throughout the <em>Document Instance</em>.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>See <a href="#time-expression-semantics"><b>N Time Expression Semantics</b></a> for further details
+on the interpretation of time expressions according to the designated time base.</p></div></div></div></div><div class="div1">
+<h2><a id="content"></a>7 Content</h2><p>This section specifies the <em>content</em> matter of the core
 vocabulary catalog.</p><div class="div2">
-<h3><a name="content-element-vocabulary" id="content-element-vocabulary"/>7.1 Content Element Vocabulary</h3><p>The following elements specify the structure and principal content aspects of a
-document instance:</p><ul><li><p><a href="#document-structure-vocabulary-tt"><b>7.1.1 tt</b></a></p></li><li><p><a href="#document-structure-vocabulary-head"><b>7.1.2 head</b></a></p></li><li><p><a href="#document-structure-vocabulary-body"><b>7.1.3 body</b></a></p></li><li><p><a href="#content-vocabulary-div"><b>7.1.4 div</b></a></p></li><li><p><a href="#content-vocabulary-p"><b>7.1.5 p</b></a></p></li><li><p><a href="#content-vocabulary-span"><b>7.1.6 span</b></a></p></li><li><p><a href="#content-vocabulary-br"><b>7.1.7 br</b></a></p></li></ul><div class="div3">
-<h4><a name="document-structure-vocabulary-tt" id="document-structure-vocabulary-tt"/>7.1.1 tt</h4><p>The <code>tt</code> element serves as the root document element of a document
-instance.</p><p>The <code>tt</code> element accepts as its children zero or one <code>head</code> element followed by
-zero or one <code>body</code> element.</p><table summary="HTML Table" id="elt-syntax-tt" class="syntax"><caption>XML Representation – Element Information Item: tt</caption><tbody><tr><td>
+<h3><a id="content-element-vocabulary"></a>7.1 Content Element Vocabulary</h3><p>The following elements specify the structure and principal content aspects of a
+<em>Document Instance</em>:</p><ul><li><p><a href="#document-structure-vocabulary-tt"><b>7.1.1 tt</b></a></p></li><li><p><a href="#document-structure-vocabulary-head"><b>7.1.2 head</b></a></p></li><li><p><a href="#document-structure-vocabulary-body"><b>7.1.3 body</b></a></p></li><li><p><a href="#content-vocabulary-div"><b>7.1.4 div</b></a></p></li><li><p><a href="#content-vocabulary-p"><b>7.1.5 p</b></a></p></li><li><p><a href="#content-vocabulary-span"><b>7.1.6 span</b></a></p></li><li><p><a href="#content-vocabulary-br"><b>7.1.7 br</b></a></p></li></ul><div class="div3">
+<h4><a id="document-structure-vocabulary-tt"></a>7.1.1 tt</h4><p>The <code>tt</code> element serves as the root document element of a <em>Document Instance</em>.</p><p>The <code>tt</code> element accepts as its children zero or one <code>head</code> element followed by
+zero or one <code>body</code> element.</p><a id="elt-syntax-tt"></a><table class="syntax"><caption>XML Representation – Element Information Item: tt</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;tt
   <a href="#style-attribute-extent">tts:extent</a> = string
@@ -1695,24 +1802,25 @@
   <em>Content:</em> <a href="#document-structure-vocabulary-head">head</a>?, <a href="#document-structure-vocabulary-body">body</a>?
 &lt;/tt&gt;
 </pre></div>
-</td></tr></tbody></table><p>The temporal beginning and ending of a document instance represented by a
-<code>tt</code> element is defined in relationship with some external
-application or presentation context. The temporal interval defined by
-these points is referred to subsequently as the <em>external time interval</em>.
-</p><p>A document instance has an implicit duration that is equal to the
-implicit duration of the <code>body</code> element of the document, if present, or zero,
-if not present.</p><p>If the <code>tts:extent</code> attribute is specified on the <code>tt</code>
+</td></tr></tbody></table><p>The <em>Root Temporal Extent</em>, i.e., the time interval over which a <em>Document Instance</em> is active, has an implicit duration that is equal to the
+implicit duration of the <code>body</code> element of the document, if the <code>body</code> element is present, or zero, if the <code>body</code> element is absent.</p><p>If the <code>tts:extent</code> attribute is specified on the <code>tt</code>
 element, then it must adhere to <a href="#style-attribute-extent"><b>8.2.7 tts:extent</b></a>, in which case it
-specifies the spatial extent of the root container region in
+specifies the spatial extent of the <em>Root Container Region</em> in
 which content regions are located and presented. If no <code>tts:extent</code>
-attribute is specified, then the spatial extent of the root container region is
-considered to be determined by the external authoring or presentation
-context. The root container origin is determined by the external
-authoring context.</p><p>An <code>xml:lang</code> attribute must be specified on the <code>tt</code> element.
+attribute is specified, then the spatial extent of the <em>Root Container Region</em> is
+considered to be determined by the <em>Document Processing Context</em>.
+The origin of the <em>Root Container Region</em> is determined by the <em>Document Processing Context</em>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>In the absence of other requirements, and if a <em>Related Media Object</em> exists, then it is recommended
+that the <em>Document Processing Context</em> determine that:</p><ul><li><p>if no <code>tts:extent</code> is specified on the root <code>tt</code> element, the extent of the <em>Root Container Region</em> be
+established as equal to the extent of the <em>Related Media Object Region</em>; and</p></li><li><p>the origin of the <em>Root Container Region</em> be established so that this region is centered in the
+<em>Related Media Object Region</em>.</p></li></ul></div><div class="note"><p class="prefix"><b>Note:</b></p><p>If an author desires to signal the (storage or image) aspect ratio of the <em>Root Container Region</em>
+without specifying its resolution, then this may be accomplished by using metadata specified
+in an external namespace, such as <code>m708:aspectRatio</code> as defined in <a href="#smpte2052">[SMPTE 2052-11]</a>, §5.4.4.
+This would permit, for example, the interchange of information that reflects the
+the semantics of <a href="#cea708d">[CEA-708-D]</a> , §4.5 “Caption Service Metadata”, “ASPECT RATIO”.</p></div><p>An <code>xml:lang</code> attribute must be specified on the <code>tt</code> element.
 If the attribute value is empty, it signifies that there is no default language that applies
-to the text contained within the document instance.</p><p>If no <code>xml:space</code> attribute is specified upon the <code>tt</code> element, then it must
+to the text contained within the <em>Document Instance</em>.</p><p>If no <code>xml:space</code> attribute is specified upon the <code>tt</code> element, then it must
 be considered as if the attribute had been specified with a value of <code>default</code>.</p></div><div class="div3">
-<h4><a name="document-structure-vocabulary-head" id="document-structure-vocabulary-head"/>7.1.2 head</h4><p>The <code>head</code> element is a container element used to group
+<h4><a id="document-structure-vocabulary-head"></a>7.1.2 head</h4><p>The <code>head</code> element is a container element used to group
 header matter, including metadata,
 profile, styling, and layout information.</p><p>The <code>head</code> element accepts as its children zero or more
 elements in the <code>Metadata.class</code> element group,
@@ -1720,13 +1828,13 @@
 <code>Parameters.class</code> element group,
 followed by zero or one <code>styling</code> element,
 followed by zero or one <code>layout</code> element.</p><p>Any metadata specified by children in the <code>Metadata.class</code>
-element group applies semantically to the document instance as a
+element group applies semantically to the <em>Document Instance</em> as a
 whole, and not just the <code>head</code> element.</p><p>Any parameters specified by children in the <code>Parameters.class</code>
-element group applies semantically to the document instance as a
+element group applies semantically to the <em>Document Instance</em> as a
 whole, and not just the <code>head</code> element.</p><p>A <code>styling</code> child element is used to specify style constructs
 that are referenced from other style constructs, by layout constructs, and by
 content elements.</p><p>A <code>layout</code> child element is used to specify layout constructs that
-are referenced by content elements.</p><table summary="HTML Table" id="elt-syntax-head" class="syntax"><caption>XML Representation – Element Information Item: head</caption><tbody><tr><td>
+are referenced by content elements.</p><a id="elt-syntax-head"></a><table class="syntax"><caption>XML Representation – Element Information Item: head</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;head
   <a href="#content-attribute-id">xml:id</a> = ID
@@ -1738,8 +1846,8 @@
 </pre></div>
 </td></tr></tbody></table><p>To the extent that time semantics apply to the content of the
 <code>head</code> element, the implied time interval of this element is
-defined to be coterminous with the external time interval.</p></div><div class="div3">
-<h4><a name="document-structure-vocabulary-body" id="document-structure-vocabulary-body"/>7.1.3 body</h4><p>The <code>body</code> element functions as a logical container and a temporal
+defined to be coterminous with the <em>Root Temporal Extent</em>.</p></div><div class="div3">
+<h4><a id="document-structure-vocabulary-body"></a>7.1.3 body</h4><p>The <code>body</code> element functions as a logical container and a temporal
 structuring element for a sequence of textual content units represented as
 logical divisions.</p><p>The <code>body</code> element accepts as its children zero or more
 elements in the <code>Metadata.class</code> element group,
@@ -1748,7 +1856,7 @@
 followed by
 zero or more <code>div</code> elements.</p><p>Any metadata specified by children in the <code>Metadata.class</code>
 element group applies semantically to the <code>body</code> element and its descendants as a whole.</p><p>Any animation elements specified by children in the <code>Animation.class</code>
-element group apply semantically to the <code>body</code> element.</p><table summary="HTML Table" id="elt-syntax-body" class="syntax"><caption>XML Representation – Element Information Item: body</caption><tbody><tr><td>
+element group apply semantically to the <code>body</code> element.</p><a id="elt-syntax-body"></a><table class="syntax"><caption>XML Representation – Element Information Item: body</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;body
   <a href="#timing-attribute-begin">begin</a> = <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>
@@ -1768,25 +1876,25 @@
 </pre></div>
 </td></tr></tbody></table><p>An author may specify a temporal interval for a <code>body</code> element using
 the <code>begin</code>, <code>dur</code>, and <code>end</code> attributes. If the begin point
-of this interval remains unspecified, then the begin point is interpreted as the begin
-point of the external time interval. Similarly, if the end point of this interval remains unspecified, then the
-end point is interpreted as the end point of the external time interval.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>A TTML document instance referenced from a SMIL presentation
+of this interval remains unspecified, then the begin point is interpreted as the beginning
+point of the <em>Root Temporal Extent</em>. Similarly, if the end point of this interval remains unspecified, then the
+end point is interpreted as the ending point of the <em>Root Temporal Extent</em>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>A <em>Document Instance</em> referenced from a SMIL presentation
 is expected to follow the same timing rules as apply to other SMIL media
 objects.</p></div><p>If relative begin or end times are specified on the <code>body</code>
-element, then these times are resolved by reference to the begin and
-end time of the external time interval.</p><p>If the external time interval is shorter than the computed duration of the
-<code>body</code> element, then the active time interval of a document instance is
-truncated to the active end point of the external time interval.</p><p>An author may associate a set of style properties with a
+element, then these times are resolved by reference to the beginning and
+ending time of the <em>Root Temporal Extent</em>.</p><p>If the <em>Root Temporal Extent</em> is shorter than the computed duration of the
+<code>body</code> element, then the active time interval of a <code>body</code> element is
+truncated to the active end point of the <em>Root Temporal Extent</em>.</p><p>An author may associate a set of style properties with a
 <code>body</code> element by means of either the <code>style</code>
 attribute or inline style attributes or a combination thereof.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>Style properties that are associated with a <code>body</code> element
-in a document instance are available for style inheritance by
+in a <em>Document Instance</em> are available for style inheritance by
 descendant content elements such as <code>div</code>, <code>p</code>,
 <code>span</code>
 and <code>br</code>.</p></div><p>If no <code>timeContainer</code> attribute is specified on a
 <code>body</code> element, then it must be interpreted as having
 <em>parallel</em>
 time containment semantics.</p></div><div class="div3">
-<h4><a name="content-vocabulary-div" id="content-vocabulary-div"/>7.1.4 div</h4><p>The <code>div</code> element functions as a logical container and a temporal
+<h4><a id="content-vocabulary-div"></a>7.1.4 div</h4><p>The <code>div</code> element functions as a logical container and a temporal
 structuring element for a sequence of textual content units represented as
 logical sub-divisions or paragraphs.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>When rendered on a continuous (non-paged) visual presentation medium,
 a <code>div</code> element is expected to generate
@@ -1807,7 +1915,7 @@
 <code>div</code> or 
 <code>p</code> elements.</p><p>Any metadata specified by children in the <code>Metadata.class</code>
 element group applies semantically to the <code>div</code> element and its descendants as a whole.</p><p>Any animation elements specified by children in the <code>Animation.class</code>
-element group apply semantically to the <code>div</code> element.</p><table summary="HTML Table" id="elt-syntax-div" class="syntax"><caption>XML Representation – Element Information Item: div</caption><tbody><tr><td>
+element group apply semantically to the <code>div</code> element.</p><a id="elt-syntax-div"></a><table class="syntax"><caption>XML Representation – Element Information Item: div</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;div
   <a href="#timing-attribute-begin">begin</a> = <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>
@@ -1828,7 +1936,7 @@
 </td></tr></tbody></table><p>An author may associate a set of style properties with a <code>div</code> element by means of either
 the <code>style</code> attribute or inline style attributes or a combination thereof.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>Style properties that are associated
 with
-a <code>div</code> element in a document instance
+a <code>div</code> element in a <em>Document Instance</em>
 are available for style inheritance by descendant content elements such as
 <code>div</code>, 
 <code>p</code>,
@@ -1836,18 +1944,18 @@
 <code>br</code>.</p></div><p>If no <code>timeContainer</code> attribute is specified on
 a <code>div</code> element, then it must be interpreted as having
 <em>parallel</em> time containment semantics.</p></div><div class="div3">
-<h4><a name="content-vocabulary-p" id="content-vocabulary-p"/>7.1.5 p</h4><p>A <code>p</code> element represents a logical paragraph, serving as
+<h4><a id="content-vocabulary-p"></a>7.1.5 p</h4><p>A <code>p</code> element represents a logical paragraph, serving as
 a transition between block level and inline level formatting semantics.</p><p>The <code>p</code> element accepts as its children zero or more
 elements in the <code>Metadata.class</code> element group,
 followed by zero or more
 elements in the <code>Animation.class</code> element group,
 followed by
-zero or more
-<code>span</code> element,
-<code>br</code> element,
-or text nodes interpreted as anonymous spans.</p><p>Any metadata specified by children in the <code>Metadata.class</code>
+zero or more intermixed
+<code>span</code> elements,
+<code>br</code> elements,
+or text nodes interpreted as an anonymous spans.</p><p>Any metadata specified by children in the <code>Metadata.class</code>
 element group applies semantically to the <code>p</code> element and its descendants as a whole.</p><p>Any animation elements specified by children in the <code>Animation.class</code>
-element group apply semantically to the <code>p</code> element.</p><table summary="HTML Table" id="elt-syntax-p" class="syntax"><caption>XML Representation – Element Information Item: p</caption><tbody><tr><td>
+element group apply semantically to the <code>p</code> element.</p><a id="elt-syntax-p"></a><table class="syntax"><caption>XML Representation – Element Information Item: p</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;p
   <a href="#timing-attribute-begin">begin</a> = <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>
@@ -1868,15 +1976,19 @@
 </td></tr></tbody></table><p>An author may associate a set of style properties with a
 <code>p</code> element by means of either the <code>style</code>
 attribute or inline style attributes or a combination thereof.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>Style properties that are associated with a <code>p</code> element
-in a document instance are available for style inheritance by
+in a <em>Document Instance</em> are available for style inheritance by
 descendant content elements such as <code>span</code> and
 <code>br</code>.</p></div><p>If no <code>timeContainer</code> attribute is specified on
 a <code>p</code> element, then it must be interpreted as having
 <em>parallel</em> time containment semantics.</p><p>If a sequence of children of a <code>p</code> element
 consists solely of character information items, then that sequence must
 be considered to be an <em>anonymous span</em> for the purpose of
-applying style properties that apply to <code>span</code> elements.</p></div><div class="div3">
-<h4><a name="content-vocabulary-span" id="content-vocabulary-span"/>7.1.6 span</h4><p>The <code>span</code> element functions as a logical container and a temporal
+applying style properties that apply to <code>span</code> elements.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The presentation semantics of TTML effectively
+implies that a <code>p</code> element constitutes a line break. In particular,
+it is associated with a block-stacking constraint both before the first
+generated line area and after the last generated line area. See
+<a href="#semantics-region-layout-step-2"><b>9.3.3 Synchronic Flow Processing</b></a> for further details.</p></div></div><div class="div3">
+<h4><a id="content-vocabulary-span"></a>7.1.6 span</h4><p>The <code>span</code> element functions as a logical container and a temporal
 structuring element for a sequence of textual content units having inline
 level formatting semantics.</p><p>When presented on a visual medium, a <code>span</code> element is intended to
 generate a sequence of inline areas, each containing one or more glyph areas.</p><p>The <code>span</code> element accepts as its children zero or more
@@ -1884,12 +1996,12 @@
 followed by zero or more
 elements in the <code>Animation.class</code> element group,
 followed by
-zero or more
+zero or more intermixed
 <code>span</code> elements,
 <code>br</code> elements,
 or text nodes interpreted as anonymous spans.</p><p>Any metadata specified by children in the <code>Metadata.class</code>
 element group applies semantically to the <code>span</code> element and its descendants as a whole.</p><p>Any animation elements specified by children in the <code>Animation.class</code>
-element group apply semantically to the <code>span</code> element.</p><table summary="HTML Table" id="elt-syntax-span" class="syntax"><caption>XML Representation – Element Information Item: span</caption><tbody><tr><td>
+element group apply semantically to the <code>span</code> element.</p><a id="elt-syntax-span"></a><table class="syntax"><caption>XML Representation – Element Information Item: span</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;span
   <a href="#timing-attribute-begin">begin</a> = <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>
@@ -1910,12 +2022,12 @@
 </td></tr></tbody></table><p>An author may associate a set of style properties with a
 <code>span</code> element by means of either the <code>style</code>
 attribute or inline style attributes or a combination thereof.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>Style properties that are associated with a <code>span</code> element
-in a document instance are available for style inheritance by
+in a <em>Document Instance</em> are available for style inheritance by
 descendant content elements such as <code>span</code> and
 <code>br</code>.</p></div><p>If no <code>timeContainer</code> attribute is specified on
 a <code>span</code> element, then it must be interpreted as having
 <em>parallel</em> time containment semantics.</p></div><div class="div3">
-<h4><a name="content-vocabulary-br" id="content-vocabulary-br"/>7.1.7 br</h4><p>The <code>br</code> element denotes an explicit line break.</p><table summary="HTML Table" id="elt-syntax-br" class="syntax"><caption>XML Representation – Element Information Item: br</caption><tbody><tr><td>
+<h4><a id="content-vocabulary-br"></a>7.1.7 br</h4><p>The <code>br</code> element denotes an explicit line break.</p><a id="elt-syntax-br"></a><table class="syntax"><caption>XML Representation – Element Information Item: br</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;br
   <a href="#style-attribute-style">style</a> = IDREFS
@@ -1930,32 +2042,30 @@
 </pre></div>
 </td></tr></tbody></table><p>When presented on a visual medium, the presence of a <code>br</code> element must be
 interpreted as a forced line break.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The visual presentation of a <code>br</code> element is
-intended to produce the same effect as the ASCII control code
-<code>CR</code>
-followed by the control code <code>NL</code> when presented on a teletype device.
+intended to produce the same effect as the control character
+<code>CR</code> (U+000D)
+followed by the control code <code>LF</code> (U+000A) when presented on a teletype device.
 Therefore, two <code>br</code> elements in sequence will produce a
 different effect than a single <code>br</code> element.</p></div></div></div><div class="div2">
-<h3><a name="content-attribute-vocabulary" id="content-attribute-vocabulary"/>7.2 Content Attribute Vocabulary</h3><p>This section defines the following common attributes used with many or all element types
+<h3><a id="content-attribute-vocabulary"></a>7.2 Content Attribute Vocabulary</h3><p>This section defines the following common attributes used with many or all element types
 in the core vocabulary catalog:</p><ul><li><p><a href="#content-attribute-id"><b>7.2.1 xml:id</b></a></p></li><li><p><a href="#content-attribute-lang"><b>7.2.2 xml:lang</b></a></p></li><li><p><a href="#content-attribute-space"><b>7.2.3 xml:space</b></a></p></li></ul><div class="div3">
-<h4><a name="content-attribute-id" id="content-attribute-id"/>7.2.1 xml:id</h4><p>The <code>xml:id</code> attribute is used as defined by
+<h4><a id="content-attribute-id"></a>7.2.1 xml:id</h4><p>The <code>xml:id</code> attribute is used as defined by
 <a href="#xmlid">[XML ID]</a>.</p><p>The <code>xml:id</code> attribute may be used with any element in the
 core vocabulary catalog.</p></div><div class="div3">
-<h4><a name="content-attribute-lang" id="content-attribute-lang"/>7.2.2 xml:lang</h4><p>The <code>xml:lang</code> attribute is used as defined by
+<h4><a id="content-attribute-lang"></a>7.2.2 xml:lang</h4><p>The <code>xml:lang</code> attribute is used as defined by
 <a href="#xml10">[XML 1.0]</a>, §2.12, <em>Language Identification</em>.</p><p>The <code>xml:lang</code> attribute must be specified on the <code>tt</code>
 element and may be specified by an instance of any other element type
-in the core vocabulary catalog.</p></div><div class="div3">
-<h4><a name="content-attribute-space" id="content-attribute-space"/>7.2.3 xml:space</h4><p>The <code>xml:space</code> attribute is used as defined by
+in the core vocabulary catalog except parameter vocabulary.</p></div><div class="div3">
+<h4><a id="content-attribute-space"></a>7.2.3 xml:space</h4><p>The <code>xml:space</code> attribute is used as defined by
 <a href="#xml10">[XML 1.0]</a>, §2.10, <em>White Space Handling</em>.</p><p>The <code>xml:space</code> attribute may be used with any element in
-the core vocabulary catalog.</p><p>The semantics of the value <code>default</code> are fixed to mean that
-when performing presentation processing of a document instance as
+the core vocabulary catalog except parameter vocabulary.</p><p>The semantics of the value <code>default</code> are fixed to mean that
+when performing presentation processing of a <em>Document Instance</em> as
 described by <a href="#semantics-region-layout-step-2"><b>9.3.3 Synchronic Flow Processing</b></a>,
 processing must occur as
 if the following properties were specified on the affected
-
 elements of an equivalent intermediate XSL-FO document:</p><ul><li><p><code>suppress-at-line-break="auto"</code></p></li><li><p><code>linefeed-treatment="treat-as-space"</code></p></li><li><p><code>white-space-collapse="true"</code></p></li><li><p><code>white-space-treatment="ignore-if-surrounding-linefeed"</code></p></li></ul><p>Similarly, the semantics of the value <code>preserve</code> are fixed to mean that
 when performing presentation processing, processing must occur as
 if the following properties were specified on the affected
-
 elements of an equivalent intermediate XSL-FO document:
 </p><ul><li><p><code>suppress-at-line-break="retain"</code></p></li><li><p><code>linefeed-treatment="preserve"</code></p></li><li><p><code>white-space-collapse="false"</code></p></li><li><p><code>white-space-treatment="preserve"</code></p></li></ul><p>When performing other types of processing intended to eventually
 result in a visual presentation by means other than those described
@@ -1963,36 +2073,33 @@
 preservation as described above should be respected. For other types
 of processing, the treatment of the <code>xml:space</code> attribute
 is processor dependent, but should respect the semantics described
-above if possible.</p></div></div></div><div class="div1">
-<h2><a name="styling" id="styling"/>8 Styling</h2><p>This section specifies the <em>styling</em> matter of the core
+above if possible.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the above four cited XSL-FO properties are defined by
+by <a href="#xsl11">[XSL 1.1]</a>, § 7.17.3, 7.16.7, 7.16.12, and 7.16.8, respectively.</p></div></div></div></div><div class="div1">
+<h2><a id="styling"></a>8 Styling</h2><p>This section specifies the <em>styling</em> matter of the core
 vocabulary catalog, where
 styling is to be understood as a separable layer of information that applies to
 content and that denotes authorial intentions about the presentation of
-that content.</p><p>
-    Styling attributes are included in TTML to enable authorial intent of presentation
-    to be included within a self-contained document. This section describes
-    the semantics of style presentation in terms of a standard processing
-    model. TTML Processors are not required to present TTML documents in any particular way; 
-    but an implementation of this model by a TTML Presentation Processor
-    that provides externally observable results that are consistent with this model is
-    likely to lead to a user experience that closely resembles the experience intended by
-    the documents' authors.
-  </p><p>
-    The semantics of TTML style presentation are described in terms of the model 
-    in <a href="#xsl11">[XSL 1.1]</a>. The intended effect of the attributes in this section 
-    are to be compatible with  the layout model of XSL. Presentation agents may however 
-    use any technology to satisfy the authorial intent of the document. In particular 
-    since <a href="#css2">[CSS2]</a> is a subset of this model, a CSS processor may be used 
-    for the features that the models have in common.
-  </p><p>No normative use of an
+that content.</p><p>Styling attributes are included in TTML to enable authorial intent of presentation
+to be included within a self-contained document. This section describes
+the semantics of style presentation in terms of a standard processing
+model. TTML Processors are not required to present <em>Document Instances</em> in any particular way; 
+but an implementation of this model by a TTML Presentation Processor
+that provides externally observable results that are consistent with this model is
+likely to lead to a user experience that closely resembles the experience intended by
+the documents' authors.</p><p>The semantics of TTML style presentation are described in terms of the model 
+in <a href="#xsl11">[XSL 1.1]</a>. The effects of the attributes in this section 
+are intended to be compatible with the layout and formatting model of XSL; however, Presentation agents
+may use any technology to satisfy the authorial intent of the document. In particular 
+since <a href="#css2">[CSS2]</a> is a subset of this model, a CSS processor may be used 
+for the features that the models have in common.</p><p>No normative use of an
 <code>&lt;?xml-stylesheet ... ?&gt;</code> processing instruction is defined
 by this specification.</p><div class="div2">
-<h3><a name="styling-element-vocabulary" id="styling-element-vocabulary"/>8.1 Styling Element Vocabulary</h3><p>The following elements specify the structure and principal styling aspects of a
-document instance:</p><ul><li><p><a href="#styling-vocabulary-styling"><b>8.1.1 styling</b></a></p></li><li><p><a href="#styling-vocabulary-style"><b>8.1.2 style</b></a></p></li></ul><div class="div3">
-<h4><a name="styling-vocabulary-styling" id="styling-vocabulary-styling"/>8.1.1 styling</h4><p>The <code>styling</code> element is a container element used to group
+<h3><a id="styling-element-vocabulary"></a>8.1 Styling Element Vocabulary</h3><p>The following elements specify the structure and principal styling aspects of a
+<em>Document Instance</em>:</p><ul><li><p><a href="#styling-vocabulary-styling"><b>8.1.1 styling</b></a></p></li><li><p><a href="#styling-vocabulary-style"><b>8.1.2 style</b></a></p></li></ul><div class="div3">
+<h4><a id="styling-vocabulary-styling"></a>8.1.1 styling</h4><p>The <code>styling</code> element is a container element used to group
 styling matter, including metadata that applies to styling matter.</p><p>The <code>styling</code> element accepts as its children zero or more
 elements in the <code>Metadata.class</code> element group, followed by
-zero or more <code>style</code> elements.</p><table summary="HTML Table" id="elt-syntax-styling" class="syntax"><caption>XML Representation – Element Information Item: styling</caption><tbody><tr><td>
+zero or more <code>style</code> elements.</p><a id="elt-syntax-styling"></a><table class="syntax"><caption>XML Representation – Element Information Item: styling</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;styling
   <a href="#content-attribute-id">xml:id</a> = ID
@@ -2004,11 +2111,11 @@
 </pre></div>
 </td></tr></tbody></table><p>To the extent that time semantics apply to the content of the
 <code>styling</code> element, the implied time interval of this element is
-defined to be coterminous with the external time interval.</p></div><div class="div3">
-<h4><a name="styling-vocabulary-style" id="styling-vocabulary-style"/>8.1.2 style</h4><p>The <code>style</code> element is used to define
+defined to be coterminous with the <em>Root Temporal Extent</em>.</p></div><div class="div3">
+<h4><a id="styling-vocabulary-style"></a>8.1.2 style</h4><p>The <code>style</code> element is used to define
 a set of style specifications expressed as a
 specified style set in accordance with
-<a href="#semantics-style-resolution-processing-sss"><b>8.4.4.2 Specified Style Set Processing</b></a>.</p><p>The <code>style</code> element accepts as its children zero or more <code>metadata</code> elements.</p><table summary="HTML Table" id="elt-syntax-style" class="syntax"><caption>XML Representation – Element Information Item: style</caption><tbody><tr><td>
+<a href="#semantics-style-resolution-processing-sss"><b>8.4.4.2 Specified Style Set Processing</b></a>.</p><p>The <code>style</code> element accepts as its children zero or more <code>metadata</code> elements.</p><a id="elt-syntax-style"></a><table class="syntax"><caption>XML Representation – Element Information Item: style</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;style
   <a href="#style-attribute-style">style</a> = IDREFS
@@ -2017,8 +2124,7 @@
   <a href="#content-attribute-space">xml:space</a> = (<em>default</em>|<em>preserve</em>)
   {<em>any attribute in TT Style namespace</em>}
   {<em>any attribute not in default or any TT namespace</em>}&gt;
-  
-  <em>Content:</em> EMPTY
+ <em>Content:</em> EMPTY
 &lt;/style&gt;
 </pre></div>
 </td></tr></tbody></table><p>If a <code>style</code> element appears as a descendant of a
@@ -2028,13 +2134,13 @@
 refer to a <code>style</code> element, then the referenced <code>style</code>
 element must appear as a descendant of the <code>styling</code> element, and
 not in any other context.</p></div></div></div><div class="div2">
-<h3><a name="styling-attribute-vocabulary" id="styling-attribute-vocabulary"/>8.2 Styling Attribute Vocabulary</h3><p>This section defines the <a href="#style-attribute-style"><b>8.2.1 style</b></a> attribute used
+<h3><a id="styling-attribute-vocabulary"></a>8.2 Styling Attribute Vocabulary</h3><p>This section defines the <a href="#style-attribute-style"><b>8.2.1 style</b></a> attribute used
 with both style definition elements as well as content elements.</p><p>In addition, this section specifies the following attributes in the TT Style Namespace
 for use with style definition elements, certain layout elements, and content elements
-that support inline style specifications:</p><ul><li><p><a href="#style-attribute-backgroundColor"><b>8.2.2 tts:backgroundColor</b></a></p></li><li><p><a href="#style-attribute-color"><b>8.2.3 tts:color</b></a></p></li><li><p><a href="#style-attribute-direction"><b>8.2.4 tts:direction</b></a></p></li><li><p><a href="#style-attribute-display"><b>8.2.5 tts:display</b></a></p></li><li><p><a href="#style-attribute-displayAlign"><b>8.2.6 tts:displayAlign</b></a></p></li><li><p><a href="#style-attribute-extent"><b>8.2.7 tts:extent</b></a></p></li><li><p><a href="#style-attribute-fontFamily"><b>8.2.8 tts:fontFamily</b></a></p></li><li><p><a href="#style-attribute-fontSize"><b>8.2.9 tts:fontSize</b></a></p></li><li><p><a href="#style-attribute-fontStyle"><b>8.2.10 tts:fontStyle</b></a></p></li><li><p><a href="#style-attribute-fontWeight"><b>8.2.11 tts:fontWeight</b></a></p></li><li><p><a href="#style-attribute-lineHeight"><b>8.2.12 tts:lineHeight</b></a></p></li><li><p><a href="#style-attribute-opacity"><b>8.2.13 tts:opacity</b></a></p></li><li><p><a href="#style-attribute-origin"><b>8.2.14 tts:origin</b></a></p></li><li><p><a href="#style-attribute-overflow"><b>8.2.15 tts:overflow</b></a></p></li><li><p><a href="#style-attribute-padding"><b>8.2.16 tts:padding</b></a></p></li><li><p><a href="#style-attribute-showBackground"><b>8.2.17 tts:showBackground</b></a></p></li><li><p><a href="#style-attribute-textAlign"><b>8.2.18 tts:textAlign</b></a></p></li><li><p><a href="#style-attribute-textDecoration"><b>8.2.19 tts:textDecoration</b></a></p></li><li><p><a href="#style-attribute-textOutline"><b>8.2.20 tts:textOutline</b></a></p></li><li><p><a href="#style-attribute-unicodeBidi"><b>8.2.21 tts:unicodeBidi</b></a></p></li><li><p><a href="#style-attribute-visibility"><b>8.2.22 tts:visibility</b></a></p></li><li><p><a href="#style-attribute-wrapOption"><b>8.2.23 tts:wrapOption</b></a></p></li><li><p><a href="#style-attribute-writingMode"><b>8.2.24 tts:writingMode</b></a></p></li><li><p><a href="#style-attribute-zIndex"><b>8.2.25 tts:zIndex</b></a></p></li></ul><p>Unless explicitly stated otherwise, linear white-space (LWSP) may
-appear between tokens of a value of a TT
+that support inline style specifications:</p><ul><li><p><a href="#style-attribute-backgroundColor"><b>8.2.2 tts:backgroundColor</b></a></p></li><li><p><a href="#style-attribute-color"><b>8.2.3 tts:color</b></a></p></li><li><p><a href="#style-attribute-direction"><b>8.2.4 tts:direction</b></a></p></li><li><p><a href="#style-attribute-display"><b>8.2.5 tts:display</b></a></p></li><li><p><a href="#style-attribute-displayAlign"><b>8.2.6 tts:displayAlign</b></a></p></li><li><p><a href="#style-attribute-extent"><b>8.2.7 tts:extent</b></a></p></li><li><p><a href="#style-attribute-fontFamily"><b>8.2.8 tts:fontFamily</b></a></p></li><li><p><a href="#style-attribute-fontSize"><b>8.2.9 tts:fontSize</b></a></p></li><li><p><a href="#style-attribute-fontStyle"><b>8.2.10 tts:fontStyle</b></a></p></li><li><p><a href="#style-attribute-fontWeight"><b>8.2.11 tts:fontWeight</b></a></p></li><li><p><a href="#style-attribute-lineHeight"><b>8.2.12 tts:lineHeight</b></a></p></li><li><p><a href="#style-attribute-opacity"><b>8.2.13 tts:opacity</b></a></p></li><li><p><a href="#style-attribute-origin"><b>8.2.14 tts:origin</b></a></p></li><li><p><a href="#style-attribute-overflow"><b>8.2.15 tts:overflow</b></a></p></li><li><p><a href="#style-attribute-padding"><b>8.2.16 tts:padding</b></a></p></li><li><p><a href="#style-attribute-showBackground"><b>8.2.17 tts:showBackground</b></a></p></li><li><p><a href="#style-attribute-textAlign"><b>8.2.18 tts:textAlign</b></a></p></li><li><p><a href="#style-attribute-textDecoration"><b>8.2.19 tts:textDecoration</b></a></p></li><li><p><a href="#style-attribute-textOutline"><b>8.2.20 tts:textOutline</b></a></p></li><li><p><a href="#style-attribute-unicodeBidi"><b>8.2.21 tts:unicodeBidi</b></a></p></li><li><p><a href="#style-attribute-visibility"><b>8.2.22 tts:visibility</b></a></p></li><li><p><a href="#style-attribute-wrapOption"><b>8.2.23 tts:wrapOption</b></a></p></li><li><p><a href="#style-attribute-writingMode"><b>8.2.24 tts:writingMode</b></a></p></li><li><p><a href="#style-attribute-zIndex"><b>8.2.25 tts:zIndex</b></a></p></li></ul><p>Unless explicitly stated otherwise, linear white-space (LWSP) must
+appear between adjacent non-terminal components of a value of a TT
 Style or TT Style Extension
-Property.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>This specification makes use of <em>lowerCamelCased</em> local
+Property value unless some other delimiter is permitted and used.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>This specification makes use of <em>lowerCamelCased</em> local
 names for style attributes that
 are based upon like-named properties defined by <a href="#xsl11">[XSL 1.1]</a>.
 This convention is likewise extended to token values of such
@@ -2043,20 +2149,23 @@
 element type. This capability permits the expression of an inheritable
 style property on ancestor elements to which the property
 does not apply.</p></div><div class="div3">
-<h4><a name="style-attribute-style" id="style-attribute-style"/>8.2.1 style</h4><p>The <code>style</code> attribute is used
-by referential style association
-to reference one or more <code>style</code>
-elements each of which define a
-specified
-style set.</p><p>The <code>style</code> attribute may be specified by an instance of the following
-element types:</p><ul><li><p><a href="#document-structure-vocabulary-body"><code>body</code></a></p></li><li><p><a href="#content-vocabulary-div"><code>div</code></a></p></li><li><p><a href="#content-vocabulary-p"><code>p</code></a></p></li><li><p><a href="#layout-vocabulary-region"><code>region</code></a></p></li><li><p><a href="#content-vocabulary-span"><code>span</code></a></p></li><li><p><a href="#styling-vocabulary-style"><code>style</code></a></p></li></ul><div class="note"><p class="prefix"><b>Note:</b></p><p>See the specific element type definitions that permit use of the
+<h4><a id="style-attribute-style"></a>8.2.1 style</h4><p>The <code>style</code> attribute is used by referential style association
+to reference one or more <code>style</code> elements each of which define a style (property) set.</p><p>The <code>style</code> attribute may be specified by an instance of the following
+element types:</p><ul><li><p><a href="#document-structure-vocabulary-body"><code>body</code></a></p></li><li><p><a href="#content-vocabulary-div"><code>div</code></a></p></li><li><p><a href="#content-vocabulary-p"><code>p</code></a></p></li><li><p><a href="#layout-vocabulary-region"><code>region</code></a></p></li><li><p><a href="#content-vocabulary-span"><code>span</code></a></p></li><li><p><a href="#styling-vocabulary-style"><code>style</code></a></p></li></ul><p>If specified, the value of a <code>style</code> attribute must
+adhere to the <code>IDREFS</code> data type defined by <a href="#xsd-2">[XML Schema Part 2]</a>,
+§ 3.3.10, and, furthermore, each IDREF must reference a <code>style</code> element
+which has a <code>styling</code> element as an ancestor.</p><p>If the same IDREF, <em>ID<sub>1</sub></em>, appears more than one time in the value of a <code>style</code>
+attribute, then there should be an intervening IDREF, <em>ID<sub>2</sub></em>, where 
+<em>ID<sub>2</sub></em> is not equal to <em>ID<sub>1</sub></em>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>This constraint is intended to discourage the use of redundant referential styling while still
+allowing the same style to be referenced multiple times in order to potentially override prior
+referenced styles, e.g., when an intervening, distinct style is referenced in the IDREFS list.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>See the specific element type definitions that permit use of the
 <code>style</code> attribute, as well as <a href="#semantics-style-association-referential"><b>8.4.1.2 Referential Styling</b></a> and <a href="#semantics-style-association-chained-referential"><b>8.4.1.3 Chained Referential Styling</b></a>, for
 further information on its semantics.</p></div></div><div class="div3">
-<h4><a name="style-attribute-backgroundColor" id="style-attribute-backgroundColor"/>8.2.2 tts:backgroundColor</h4><p>The <code>tts:backgroundColor</code> attribute is used to specify a style property that
+<h4><a id="style-attribute-backgroundColor"></a>8.2.2 tts:backgroundColor</h4><p>The <code>tts:backgroundColor</code> attribute is used to specify a style property that
 defines the background color of a region or an area generated by content flowed into a region.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-backgroundColor" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-backgroundColor"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <a href="#style-value-color">&lt;color&gt;</a>
 </td></tr><tr><td><em>Initial:</em></td><td><code>transparent</code></td></tr><tr><td><em>Applies to:</em></td><td>
 <a href="#document-structure-vocabulary-body"><code>body</code></a>,
@@ -2066,7 +2175,7 @@
 <a href="#content-vocabulary-span"><code>span</code></a>
 </td></tr><tr><td><em>Inherited:</em></td><td>no</td></tr><tr><td><em>Percentages:</em></td><td>N/A</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>For the purpose of determining applicability of this style property,
 each character child of a <code>p</code> element is considered to be enclosed in an anonymous
-span.</p><p>The <code>tts:backgroundColor</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-backgroundColor-example-1" class="example"><caption>Example Fragment – Background Color</caption><tbody><tr><td>
+span.</p><p>The <code>tts:backgroundColor</code> style is illustrated by the following example.</p><a id="style-attribute-backgroundColor-example-1"></a><table class="example"><caption>Example Fragment – Background Color</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="306px 114px"/&gt;
@@ -2081,12 +2190,13 @@
   How &lt;span <span class="strong">tts:backgroundColor="green"</span>&gt;I wonder&lt;/span&gt; where you're at!
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-backgroundColor-example-1-images" class="example-images"><caption>Example Rendition – Background Color</caption><tbody><tr><td><img src="images/backgroundColor.png" alt="TTML backgroundColor style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-color" id="style-attribute-color"/>8.2.3 tts:color</h4><p>The <code>tts:color</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-backgroundColor-example-1-images"></a><table class="example-images"><caption>Example Rendition – Background Color</caption><tbody><tr><td><img src="images/backgroundColor.png" alt="TTML backgroundColor style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property represented by this attribute are based upon 
+that defined by <a href="#xsl11">[XSL 1.1]</a>, § 7.8.2.</p></div></div><div class="div3">
+<h4><a id="style-attribute-color"></a>8.2.3 tts:color</h4><p>The <code>tts:color</code> attribute is used to specify a style property that
 defines the foreground color of marks associated with an area generated by content flowed into a region.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-color" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-color"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <a href="#style-value-color">&lt;color&gt;</a>
 </td></tr><tr><td><em>Initial:</em></td><td>see prose</td></tr><tr><td><em>Applies to:</em></td><td>
 <a href="#content-vocabulary-span"><code>span</code></a>
@@ -2096,7 +2206,7 @@
 is considered to be implementation dependent. In the absence of
 end-user preference information, a conformant presentation processor
 should use an initial value that is highly contrastive to the
-background color of the root container region.</p><p>The <code>tts:color</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-color-example-1" class="example"><caption>Example Fragment – Color</caption><tbody><tr><td>
+background color of the <em>Root Container Region</em>.</p><p>The <code>tts:color</code> style is illustrated by the following example.</p><a id="style-attribute-color-example-1"></a><table class="example"><caption>Example Fragment – Color</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:backgroundColor="black"/&gt;
@@ -2110,13 +2220,15 @@
   I'll try and tell you what I mean.
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-color-example-1-images" class="example-images"><caption>Example Rendition – Color</caption><tbody><tr><td><img src="images/color.png" alt="TTML color style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-direction" id="style-attribute-direction"/>8.2.4 tts:direction</h4><p>The <code>tts:direction</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-color-example-1-images"></a><table class="example-images"><caption>Example Rendition – Color</caption><tbody><tr><td><img src="images/color.png" alt="TTML color style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.18.1.</p></div></div><div class="div3">
+<h4><a id="style-attribute-direction"></a>8.2.4 tts:direction</h4><p>The <code>tts:direction</code> attribute is used to specify a style property that
 defines the directionality of an embedding or override according to
 the Unicode bidirectional algorithm.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-direction" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-direction"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>ltr</code> |
 <code>rtl</code>
 </td></tr><tr><td><em>Initial:</em></td><td>
@@ -2127,7 +2239,7 @@
 </td></tr><tr><td><em>Inherited:</em></td><td>yes</td></tr><tr><td><em>Percentages:</em></td><td>N/A</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>For the purpose of determining applicability of this style property,
 each character child of a <code>p</code> element is considered to be enclosed in an anonymous
 span.</p><p>If a specified value of this attribute is not supported,
-then a presentation processor must ignore the attribute.</p><p>The <code>tts:direction</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-direction-example-1" class="example"><caption>Example Fragment – Direction</caption><tbody><tr><td>
+then a presentation processor must ignore the attribute.</p><p>The <code>tts:direction</code> style is illustrated by the following example.</p><a id="style-attribute-direction-example-1"></a><table class="example"><caption>Example Fragment – Direction</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="265px 84px"/&gt;
@@ -2144,15 +2256,17 @@
   &lt;span tts:unicodeBidi="bidiOverride" <span class="strong">tts:direction="rtl"</span>&gt;where the tourists snore.&lt;/span&gt;
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-direction-example-1-images" class="example-images"><caption>Example Rendition – Direction</caption><tbody><tr><td>
-<img src="images/direction.png" alt="TTML direction style property"/>
-</td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-display" id="style-attribute-display"/>8.2.5 tts:display</h4><p>The <code>tts:display</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-direction-example-1-images"></a><table class="example-images"><caption>Example Rendition – Direction</caption><tbody><tr><td>
+<img src="images/direction.png" alt="TTML direction style property">
+</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.29.1.</p></div></div><div class="div3">
+<h4><a id="style-attribute-display"></a>8.2.5 tts:display</h4><p>The <code>tts:display</code> attribute is used to specify a style property that
 defines whether an element is a candidate for layout and composition
 in a region.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-display" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-display"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>auto</code> |
 <code>none</code>
 </td></tr><tr><td><em>Initial:</em></td><td>
@@ -2169,7 +2283,7 @@
 then the affected element is a candidate for region layout and
 presentation; however, if the value is <code>none</code>, then the
 affected element and its descendants must be considered ineligible for region
-layout and presentation.</p><p>The <code>tts:display</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-display-example-1" class="example"><caption>Example Fragment – Display</caption><tbody><tr><td>
+layout and presentation.</p><p>The <code>tts:display</code> style is illustrated by the following example.</p><a id="style-attribute-display-example-1"></a><table class="example"><caption>Example Fragment – Display</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="369px 119px"
@@ -2198,22 +2312,23 @@
   &lt;/p&gt;
 &lt;/div&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-display-example-1-images" class="example-images"><caption>Example Rendition – Display</caption><tbody><tr><td>
-<img src="images/display_0.png" alt="TTML display style property - [0,1)"/>
-</td></tr><tr><td>
-<img src="images/display_1.png" alt="TTML display style property - [1,2)"/>
+</td></tr></tbody></table><p></p><a id="style-attribute-display-example-1-images"></a><table class="example-images"><caption>Example Rendition – Display</caption><tbody><tr><td>
+<img src="images/display_0.png" alt="TTML display style property - [0,1)">
 </td></tr><tr><td>
-<img src="images/display_2.png" alt="TTML display style property - [2,3)"/>
+<img src="images/display_1.png" alt="TTML display style property - [1,2)">
 </td></tr><tr><td>
-<img src="images/display_3.png" alt="TTML display style property - [3,4)"/>
+<img src="images/display_2.png" alt="TTML display style property - [2,3)">
 </td></tr><tr><td>
-<img src="images/display_4.png" alt="TTML display style property - [4,5)"/>
-</td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-displayAlign" id="style-attribute-displayAlign"/>8.2.6 tts:displayAlign</h4><p>The <code>tts:displayAlign</code> attribute is used to specify a style property that
+<img src="images/display_3.png" alt="TTML display style property - [3,4)">
+</td></tr><tr><td>
+<img src="images/display_4.png" alt="TTML display style property - [4,5)">
+</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#css2">[CSS2]</a>, § 9.2.4.</p></div></div><div class="div3">
+<h4><a id="style-attribute-displayAlign"></a>8.2.6 tts:displayAlign</h4><p>The <code>tts:displayAlign</code> attribute is used to specify a style property that
 defines the alignment of block areas in the block progression direction.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-displayAlign" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-displayAlign"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>before</code> |
 <code>center</code> |
 <code>after</code>
@@ -2223,7 +2338,7 @@
 <a href="#layout-vocabulary-region"><code>region</code></a>
 </td></tr><tr><td><em>Inherited:</em></td><td>no</td></tr><tr><td><em>Percentages:</em></td><td>N/A</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>before</code> were specified.</p><p>The <code>tts:displayAlign</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-displayAlign-example-1" class="example"><caption>Example Fragment – Display Align</caption><tbody><tr><td>
+value <code>before</code> were specified.</p><p>The <code>tts:displayAlign</code> style is illustrated by the following example.</p><a id="style-attribute-displayAlign-example-1"></a><table class="example"><caption>Example Fragment – Display Align</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="128px 66px" tts:origin="0px 0px"
@@ -2257,40 +2372,32 @@
   &lt;p region="r4"&gt;They sent an&lt;br/&gt; answer back to me.&lt;/p&gt;
 &lt;/div&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-displayAlign-example-1-images" class="example-images"><caption>Example Rendition – Display Align</caption><tbody><tr><td><img src="images/displayAlign.png" alt="TTML displayAlign style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-extent" id="style-attribute-extent"/>8.2.7 tts:extent</h4><p>The <code>tts:extent</code> attribute is used to specify the
+</td></tr></tbody></table><p></p><a id="style-attribute-displayAlign-example-1-images"></a><table class="example-images"><caption>Example Rendition – Display Align</caption><tbody><tr><td><img src="images/displayAlign.png" alt="TTML displayAlign style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.14.4.</p></div></div><div class="div3">
+<h4><a id="style-attribute-extent"></a>8.2.7 tts:extent</h4><p>The <code>tts:extent</code> attribute is used to specify the
 <em>width</em> and <em>height</em> of a region area
-(which may be the root container region).</p><p>This attribute may be specified by any
+(which may be the <em>Root Container Region</em>).</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-extent" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-extent"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>auto</code> |
 <a href="#style-value-length">&lt;length&gt;</a> <a href="#style-value-length">&lt;length&gt;</a>
 </td></tr><tr><td><em>Initial:</em></td><td><code>auto</code></td></tr><tr><td><em>Applies to:</em></td><td>
 <a href="#document-structure-vocabulary-tt"><code>tt</code></a>,
 <a href="#layout-vocabulary-region"><code>region</code></a>
-</td></tr><tr><td><em>Inherited:</em></td><td>no</td></tr><tr><td><em>Percentages:</em></td><td>relative to width and height of root container region</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>If the value of this attribute consists of two <a href="#style-value-length">&lt;length&gt;</a>
+</td></tr><tr><td><em>Inherited:</em></td><td>no</td></tr><tr><td><em>Percentages:</em></td><td>relative to width and height of <em>Root Container Region</em></td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>If the value of this attribute consists of two <a href="#style-value-length">&lt;length&gt;</a>
 specifications, then they must be interpreted as <em>width</em>
 and <em>height</em>, where the first specification is the
-<em>width</em>, and the second specification is the
-<em>height</em>.</p><p>If the value of this attribute is <code>auto</code>, then the initial value
-of the style property must be considered to be the same as the root container extent.
-</p><p>
-The root container extent is determined either by a
+<em>width</em>, and the second specification is the <em>height</em>.</p><p>The <a href="#style-value-length">&lt;length&gt;</a> value(s) used to express extent must be non-negative.</p><p>If the value of this attribute is <code>auto</code>, then the initial value
+of the style property must be considered to be the same as the extent of the <em>Root Container Region</em>.</p><p>The extent of the <em>Root Container Region</em> is determined either by a
 <code>tts:extent</code> specified on the <code>tt</code> element, if
-present, or by the external authoring context, if not present.
-If
-<code>tts:extent</code> is specified on the <code>tt</code> element,
-then
-the width and height
-must be
-expressed in terms of two
-<a href="#style-value-length">&lt;length&gt;</a> specifications,
-and
-these specifications must be expressed as non-percentage,
-definite lengths using pixel units.</p><p>If a specified value of this attribute is not supported,
+present, or as described by <a href="#document-structure-vocabulary-tt"><b>7.1.1 tt</b></a> if not present.
+If <code>tts:extent</code> is specified on the <code>tt</code> element, then
+the width and height must be expressed in terms of two <a href="#style-value-length">&lt;length&gt;</a> specifications,
+and these specifications must be expressed as non-percentage, definite lengths using pixel units.</p><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>auto</code> were specified.</p><p>The <code>tts:extent</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-extent-example-1" class="example"><caption>Example Fragment – Extent</caption><tbody><tr><td>
+value <code>auto</code> were specified.</p><p>The <code>tts:extent</code> style is illustrated by the following example.</p><a id="style-attribute-extent-example-1"></a><table class="example"><caption>Example Fragment – Extent</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style <span class="strong">tts:extent="330px 122px"</span>/&gt;
@@ -2307,16 +2414,16 @@
   I must sugar my hair."
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-extent-example-1-images" class="example-images"><caption>Example Rendition – Extent</caption><tbody><tr><td><img src="images/extent.png" alt="TTML extent style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-fontFamily" id="style-attribute-fontFamily"/>8.2.8 tts:fontFamily</h4><p>The <code>tts:fontFamily</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-extent-example-1-images"></a><table class="example-images"><caption>Example Rendition – Extent</caption><tbody><tr><td><img src="images/extent.png" alt="TTML extent style property"></td></tr></tbody></table></div><div class="div3">
+<h4><a id="style-attribute-fontFamily"></a>8.2.8 tts:fontFamily</h4><p>The <code>tts:fontFamily</code> attribute is used to specify a style property that
 defines the font family from which glyphs are selected for glyph areas generated
 by content flowed into a region.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-fontFamily" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-fontFamily"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 (<a href="#style-value-familyName">&lt;familyName&gt;</a> | <a href="#style-value-genericFamilyName">&lt;genericFamilyName&gt;</a>)
 (<code>","</code>
- (<a href="#style-value-familyName">&lt;familyName&gt;</a> | <a href="#style-value-genericFamilyName">&lt;genericFamilyName&gt;</a>))*
+&nbsp;(<a href="#style-value-familyName">&lt;familyName&gt;</a> | <a href="#style-value-genericFamilyName">&lt;genericFamilyName&gt;</a>))*
 </td></tr><tr><td><em>Initial:</em></td><td><code>default</code></td></tr><tr><td><em>Applies to:</em></td><td>
 <a href="#content-vocabulary-span"><code>span</code></a>
 </td></tr><tr><td><em>Inherited:</em></td><td>yes</td></tr><tr><td><em>Percentages:</em></td><td>N/A</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The initial value, <code>default</code>, is a generic font family name, and is
@@ -2327,7 +2434,7 @@
 to an available font family that has similar typographic
 characteristics, or, in the absence of such a mapping, it must
 interpret the font family as if the value <code>default</code> were
-specified.</p><p>The <code>tts:fontFamily</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-fontFamily-example-1" class="example"><caption>Example Fragment – Font Family</caption><tbody><tr><td>
+specified.</p><p>The <code>tts:fontFamily</code> style is illustrated by the following example.</p><a id="style-attribute-fontFamily-example-1"></a><table class="example"><caption>Example Fragment – Font Family</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="474px 146px"/&gt;
@@ -2353,18 +2460,18 @@
   &lt;/p&gt;
 &lt;/div&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-fontFamily-example-1-images" class="example-images"><caption>Example Rendition – Font Family</caption><tbody><tr><td><img src="images/fontFamily.png" alt="TTML fontFamily style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-fontSize" id="style-attribute-fontSize"/>8.2.9 tts:fontSize</h4><p>The <code>tts:fontSize</code> attribute is used to specify a style property
+</td></tr></tbody></table><p></p><a id="style-attribute-fontFamily-example-1-images"></a><table class="example-images"><caption>Example Rendition – Font Family</caption><tbody><tr><td><img src="images/fontFamily.png" alt="TTML fontFamily style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.9.2.</p></div></div><div class="div3">
+<h4><a id="style-attribute-fontSize"></a>8.2.9 tts:fontSize</h4><p>The <code>tts:fontSize</code> attribute is used to specify a style property
 that defines the font size for glyphs that are selected for glyph areas
-generated by content flowed into a region, where font size is interpreted as a
-scaling transform to the font's design EM square.</p><p>This attribute may be specified by any
-element type
+generated by content flowed into a region.</p><p>This attribute may be specified by any element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-fontSize" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-fontSize"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <a href="#style-value-length">&lt;length&gt;</a> <a href="#style-value-length">&lt;length&gt;</a>?
 </td></tr><tr><td><em>Initial:</em></td><td><code>1c</code></td></tr><tr><td><em>Applies to:</em></td><td>
 <a href="#content-vocabulary-span"><code>span</code></a>
-</td></tr><tr><td><em>Inherited:</em></td><td>yes</td></tr><tr><td><em>Percentages:</em></td><td>relative to parent element's font size</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>If a single <a href="#style-value-length">&lt;length&gt;</a> value is specified, then this length applies
+</td></tr><tr><td><em>Inherited:</em></td><td>yes</td></tr><tr><td><em>Percentages:</em></td><td>relative to parent element's font size, or if no parent element, then relative to the <em>Computed Cell Size</em></td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>If a single <a href="#style-value-length">&lt;length&gt;</a> value is specified, then this length applies
 equally to horizontal and vertical scaling of a glyph's EM square; if two
 <a href="#style-value-length">&lt;length&gt;</a> values are specified, then the first expresses the horizontal
 scaling and the second expresses vertical scaling.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>Use of independent horizontal and vertical font sizes is expected to be used
@@ -2373,9 +2480,19 @@
 units of the <a href="#style-value-length">&lt;length&gt;</a> values must be the same.</p><p>The <a href="#style-value-length">&lt;length&gt;</a> value(s) used to express font size must be non-negative.</p><p>For the purpose of determining applicability of this style property,
 each character child of a <code>p</code> element is considered to be enclosed in an anonymous
 span.</p><p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>1c</code> were specified.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The expression <code>1c</code> means one cell, where <code>'c'</code> expresses
-the <em>cell</em> length unit as defined by <a href="#style-value-length"><b>8.3.9 &lt;length&gt;</b></a>.</p></div><p>The <code>tts:fontSize</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-fontSize-example-1" class="example"><caption>Example Fragment – Font Size</caption><tbody><tr><td>
+then a presentation processor must interpret the attribute as if the closest supported value were
+specified.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The expression <code>1c</code> means one cell, where <code>'c'</code> expresses
+the <em>cell</em> length unit as defined by <a href="#style-value-length"><b>8.3.9 &lt;length&gt;</b></a>.
+When a single &lt;length&gt; is expressed using cell units, then it refers to the height of
+the <em>Computed Cell Size</em>.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>As specified above, the use of percentage units to express font size are interpreted as
+relative to <em>Computed Cell Size</em> when there is no parent element. For example, if cell resolution
+is 32 by 15, and the extent of the <em>Root Container Region</em> is 640 by 480, then the
+<em>Computed Cell Size</em> is [20px, 32px], i.e., 640px/32 (width) and 480px/15 (height). Consequently, if
+<code>tts:fontSize</code> were specified as 75% on the root <code>tt</code> element, then this would
+be equivalent to specifying 24px, i.e., 32px cell height * 75%.
+If two length expressions (independent horizontal and vertical font scaling) were specified, e.g.,
+"80% 75%", then this would be equivalent to specifying "16px 24px", i.e., 80% of 20px cell width is
+16px, and 75% of 32px cell height is 24px.</p></div><p>The <code>tts:fontSize</code> style is illustrated by the following example.</p><a id="style-attribute-fontSize-example-1"></a><table class="example"><caption>Example Fragment – Font Size</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="299px 97px"/&gt;
@@ -2394,15 +2511,18 @@
   that is &lt;span <span class="strong">tts:fontSize="24px"</span>&gt;pleasant&lt;/span&gt; to drink.
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-fontSize-example-1-images" class="example-images"><caption>Example Rendition – Font Size</caption><tbody><tr><td><img src="images/fontSize.png" alt="TTML fontSize style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-fontStyle" id="style-attribute-fontStyle"/>8.2.10 tts:fontStyle</h4><p>The <code>tts:fontStyle</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-fontSize-example-1-images"></a><table class="example-images"><caption>Example Rendition – Font Size</caption><tbody><tr><td><img src="images/fontSize.png" alt="TTML fontSize style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.9.4. The addition of a second length component to permit specifying font
+width and height independently is an extension introduced by TTML.</p></div></div><div class="div3">
+<h4><a id="style-attribute-fontStyle"></a>8.2.10 tts:fontStyle</h4><p>The <code>tts:fontStyle</code> attribute is used to specify a style property that
 defines the font style to apply to glyphs that are selected for glyph areas generated
 by content flowed into a region, where the mapping from font
 style value to specific font face or style parameterization is not determined
 by this specification.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-fontStyle" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-fontStyle"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>normal</code> |
 <code>italic</code> |
 <code>oblique</code>
@@ -2411,13 +2531,13 @@
 </td></tr><tr><td><em>Inherited:</em></td><td>yes</td></tr><tr><td><em>Percentages:</em></td><td>N/A</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>For the purpose of determining applicability of this style property,
 each character child of a <code>p</code> element is considered to be enclosed in an anonymous
 span.</p><p>Use of the value <code>oblique</code>
-denote a shear transformation (at an unspecified
+denotes a shear transformation (at an unspecified
 angle) in the inline progression dimension.</p><p>If a specified font style is not available, then a
 presentation processor must attempt to map the specified font style
 to an available font style that has similar typographic
 characteristics, or, in the absence of such a mapping, it must
 interpret the font style as if the value <code>normal</code> were
-specified.</p><p>The <code>tts:fontStyle</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-fontStyle-example-1" class="example"><caption>Example Fragment – Font Style</caption><tbody><tr><td>
+specified.</p><p>The <code>tts:fontStyle</code> style is illustrated by the following example.</p><a id="style-attribute-fontStyle-example-1"></a><table class="example"><caption>Example Fragment – Font Style</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="331px 84px"/&gt;
@@ -2433,15 +2553,17 @@
   Take pen and ink, and &lt;span <span class="strong">tts:fontStyle="italic"</span>&gt;write it down.&lt;/span&gt;
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-fontStyle-example-1-images" class="example-images"><caption>Example Rendition – Font Style</caption><tbody><tr><td><img src="images/fontStyle.png" alt="TTML fontStyle style property"/></td></tr></tbody></table><p/></div><div class="div3">
-<h4><a name="style-attribute-fontWeight" id="style-attribute-fontWeight"/>8.2.11 tts:fontWeight</h4><p>The <code>tts:fontWeight</code> attribute is used to specify a style property
+</td></tr></tbody></table><p></p><a id="style-attribute-fontStyle-example-1-images"></a><table class="example-images"><caption>Example Rendition – Font Style</caption><tbody><tr><td><img src="images/fontStyle.png" alt="TTML fontStyle style property"></td></tr></tbody></table><p></p><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.9.7.</p></div></div><div class="div3">
+<h4><a id="style-attribute-fontWeight"></a>8.2.11 tts:fontWeight</h4><p>The <code>tts:fontWeight</code> attribute is used to specify a style property
 that defines the font weight to apply to glyphs that are selected for glyph
 areas generated by content flowed into a region, where the mapping from font
 weight value to specific font face or weight parameterization is not determined
 by this specification.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-fontWeight" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-fontWeight"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>normal</code> |
 <code>bold</code>
 </td></tr><tr><td><em>Initial:</em></td><td><code>normal</code></td></tr><tr><td><em>Applies to:</em></td><td>
@@ -2453,7 +2575,7 @@
 to an available font weight that has similar typographic
 characteristics, or, in the absence of such a mapping, it must
 interpret the font weight as if the value <code>normal</code> were
-specified.</p><p>The <code>tts:fontWeight</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-fontWeight-example-1" class="example"><caption>Example Fragment – Font Weight</caption><tbody><tr><td>
+specified.</p><p>The <code>tts:fontWeight</code> style is illustrated by the following example.</p><a id="style-attribute-fontWeight-example-1"></a><table class="example"><caption>Example Fragment – Font Weight</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="376px 95px"/&gt;
@@ -2471,12 +2593,14 @@
   &lt;span <span class="strong">tts:fontWeight="bold"</span>&gt;but said I could not swim.&lt;/span&gt;
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-fontWeight-example-1-images" class="example-images"><caption>Example Rendition – Font Weight</caption><tbody><tr><td><img src="images/fontWeight.png" alt="TTML fontWeight style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-lineHeight" id="style-attribute-lineHeight"/>8.2.12 tts:lineHeight</h4><p>The <code>tts:lineHeight</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-fontWeight-example-1-images"></a><table class="example-images"><caption>Example Rendition – Font Weight</caption><tbody><tr><td><img src="images/fontWeight.png" alt="TTML fontWeight style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.9.9.</p></div></div><div class="div3">
+<h4><a id="style-attribute-lineHeight"></a>8.2.12 tts:lineHeight</h4><p>The <code>tts:lineHeight</code> attribute is used to specify a style property that
 defines the inter-baseline separation between line areas generated by content flowed into a region.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-lineHeight" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-lineHeight"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>normal</code> |
 <a href="#style-value-length">&lt;length&gt;</a>
 </td></tr><tr><td><em>Initial:</em></td><td><code>normal</code></td></tr><tr><td><em>Applies to:</em></td><td>
@@ -2487,7 +2611,7 @@
 descendant element.</p><p>If specified as a <a href="#style-value-length">&lt;length&gt;</a>, then the length must
 be non-negative.</p><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>normal</code> were specified.</p><p>The <code>tts:lineHeight</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-lineHeight-example-1" class="example"><caption>Example Fragment – Line Height</caption><tbody><tr><td>
+value <code>normal</code> were specified.</p><p>The <code>tts:lineHeight</code> style is illustrated by the following example.</p><a id="style-attribute-lineHeight-example-1"></a><table class="example"><caption>Example Fragment – Line Height</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="255px 190px"/&gt;
@@ -2509,22 +2633,26 @@
   "The bitterness of Life.
 "&lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-lineHeight-example-1-images" class="example-images"><caption>Example Rendition – Line Height</caption><tbody><tr><td><img src="images/lineHeight.png" alt="TTML lineHeight style property"/></td></tr></tbody></table><p/></div><div class="div3">
-<h4><a name="style-attribute-opacity" id="style-attribute-opacity"/>8.2.13 tts:opacity</h4><p>The <code>tts:opacity</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-lineHeight-example-1-images"></a><table class="example-images"><caption>Example Rendition – Line Height</caption><tbody><tr><td><img src="images/lineHeight.png" alt="TTML lineHeight style property"></td></tr></tbody></table><p></p><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.16.4. Furthermore, it is the intention of this specification that the
+allocation rectangle of a line be consistent with the <span class="strong">per-inline-height-rectangle</span>
+as defined by <a href="#xsl11">[XSL 1.1]</a>, § 4.5, i.e., that a CSS-style line box stacking strategy be used.
+</p></div></div><div class="div3">
+<h4><a id="style-attribute-opacity"></a>8.2.13 tts:opacity</h4><p>The <code>tts:opacity</code> attribute is used to specify a style property that
 defines the opacity (or conversely, the transparency)
 of marks associated with a region.</p><p>When presented onto a visual medium, the opacity of the region is applied uniformly and on a linear scale
 to all marks produced by content targeted to the
 region.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-opacity" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-opacity"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <a href="#style-value-alpha">&lt;alpha&gt;</a>
 </td></tr><tr><td><em>Initial:</em></td><td>
 <code>1.0</code>
 </td></tr><tr><td><em>Applies to:</em></td><td>
 <a href="#layout-vocabulary-region"><code>region</code></a>
-</td></tr><tr><td><em>Inherited:</em></td><td>no</td></tr><tr><td><em>Percentages:</em></td><td>N/A</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>An <a href="#style-value-alpha">&lt;alpha&gt;</a> value greater
-than 1.0 must be considered equivalent to an <a href="#style-value-alpha">&lt;alpha&gt;</a> value of 1.0.</p><p>The <code>tts:opacity</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-opacity-example-1" class="example"><caption>Example Fragment – Opacity</caption><tbody><tr><td>
+</td></tr><tr><td><em>Inherited:</em></td><td>no</td></tr><tr><td><em>Percentages:</em></td><td>N/A</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>The <code>tts:opacity</code> style is illustrated by the following example.</p><a id="style-attribute-opacity-example-1"></a><table class="example"><caption>Example Fragment – Opacity</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1" dur="5s"&gt;
   &lt;set begin="0s" dur="1s" <span class="strong">tts:opacity="1.00"</span>/&gt;
@@ -2543,35 +2671,35 @@
   The sun was shining on the sea
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-opacity-example-1-images" class="example-images"><caption>Example Rendition – Opacity</caption><tbody><tr><td>
-<img src="images/opacity_0.png" alt="TTML opacity style property - [0,1)"/>
-</td></tr><tr><td>
-<img src="images/opacity_1.png" alt="TTML opacity style property - [1,2)"/>
-</td></tr><tr><td>
-<img src="images/opacity_2.png" alt="TTML opacity style property - [2,3)"/>
+</td></tr></tbody></table><p></p><a id="style-attribute-opacity-example-1-images"></a><table class="example-images"><caption>Example Rendition – Opacity</caption><tbody><tr><td>
+<img src="images/opacity_0.png" alt="TTML opacity style property - [0,1)">
 </td></tr><tr><td>
-<img src="images/opacity_3.png" alt="TTML opacity style property - [3,4)"/>
+<img src="images/opacity_1.png" alt="TTML opacity style property - [1,2)">
 </td></tr><tr><td>
-<img src="images/opacity_4.png" alt="TTML opacity style property - [4,5)"/>
-</td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-origin" id="style-attribute-origin"/>8.2.14 tts:origin</h4><p>The <code>tts:origin</code> attribute is used to specify the
+<img src="images/opacity_2.png" alt="TTML opacity style property - [2,3)">
+</td></tr><tr><td>
+<img src="images/opacity_3.png" alt="TTML opacity style property - [3,4)">
+</td></tr><tr><td>
+<img src="images/opacity_4.png" alt="TTML opacity style property - [4,5)">
+</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#css3-color">[CSS3 Color]</a>,
+§ 3.2.</p></div></div><div class="div3">
+<h4><a id="style-attribute-origin"></a>8.2.14 tts:origin</h4><p>The <code>tts:origin</code> attribute is used to specify the
 <em>x</em> and <em>y</em> coordinates of the origin of a
-region area with respect to the origin of the root container extent,
-if specified, or the external authoring context, if not specified.</p><p>This attribute may be specified by any
+region area with respect to the origin of the <em>Root Container Region</em>.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-origin" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-origin"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>auto</code> |
 <a href="#style-value-length">&lt;length&gt;</a> <a href="#style-value-length">&lt;length&gt;</a>
 </td></tr><tr><td><em>Initial:</em></td><td><code>auto</code></td></tr><tr><td><em>Applies to:</em></td><td>
 <a href="#layout-vocabulary-region"><code>region</code></a>
-</td></tr><tr><td><em>Inherited:</em></td><td>no</td></tr><tr><td><em>Percentages:</em></td><td>relative to width and height of root container region</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>If the value of this attribute consists of two <a href="#style-value-length">&lt;length&gt;</a> specifications,
+</td></tr><tr><td><em>Inherited:</em></td><td>no</td></tr><tr><td><em>Percentages:</em></td><td>relative to width and height of <em>Root Container Region</em></td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>If the value of this attribute consists of two <a href="#style-value-length">&lt;length&gt;</a> specifications,
 then they must be interpreted as <em>x</em> and <em>y</em> coordinates, where the first specification
 is the <em>x</em> coordinate, and the second specification is the <em>y</em> coordinate.</p><p>If the value of this attribute is <code>auto</code>, then the initial value
-of the style property must be considered to be the same as the root container
-origin.</p><p>If a specified value of this attribute is not supported,
+of the style property must be considered to be the same as the origin of the <em>Root Container Region</em>.</p><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>auto</code> were specified.</p><p>The <code>tts:origin</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-origin-example-1" class="example"><caption>Example Fragment – Origin</caption><tbody><tr><td>
+value <code>auto</code> were specified.</p><p>The <code>tts:origin</code> style is illustrated by the following example.</p><a id="style-attribute-origin-example-1"></a><table class="example"><caption>Example Fragment – Origin</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style <span class="strong">tts:origin="40px 40px"</span>/&gt;
@@ -2588,13 +2716,13 @@
    To simper at a table-cloth!"
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-origin-example-1-images" class="example-images"><caption>Example Rendition – Origin</caption><tbody><tr><td><img src="images/origin.png" alt="TTML origin style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-overflow" id="style-attribute-overflow"/>8.2.15 tts:overflow</h4><p>The <code>tts:overflow</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-origin-example-1-images"></a><table class="example-images"><caption>Example Rendition – Origin</caption><tbody><tr><td><img src="images/origin.png" alt="TTML origin style property"></td></tr></tbody></table></div><div class="div3">
+<h4><a id="style-attribute-overflow"></a>8.2.15 tts:overflow</h4><p>The <code>tts:overflow</code> attribute is used to specify a style property that
 defines whether a region area is clipped or not if the descendant areas of the region overflow
 its extent.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-overflow" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-overflow"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>visible</code> |
 <code>hidden</code>
 </td></tr><tr><td><em>Initial:</em></td><td><code>hidden</code></td></tr><tr><td><em>Applies to:</em></td><td>
@@ -2611,7 +2739,7 @@
 region is <code>visible</code> and if the applicable <code>tts:wrapOption</code>
 style is <code>noWrap</code>.</p></div><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>hidden</code> were specified.</p><p>The <code>tts:overflow</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-overflow-example-1" class="example"><caption>Example Fragment – Overflow</caption><tbody><tr><td>
+value <code>hidden</code> were specified.</p><p>The <code>tts:overflow</code> style is illustrated by the following example.</p><a id="style-attribute-overflow-example-1"></a><table class="example"><caption>Example Fragment – Overflow</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="232px 40px"/&gt;
@@ -2647,15 +2775,17 @@
   And all of us are fat!"
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-overflow-example-1-images" class="example-images"><caption>Example Rendition – Overflow</caption><tbody><tr><td><img src="images/overflow.png" alt="TTML overflow style property"/></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the above example, the <code>tts:noWrap</code> is set to
+</td></tr></tbody></table><p></p><a id="style-attribute-overflow-example-1-images"></a><table class="example-images"><caption>Example Rendition – Overflow</caption><tbody><tr><td><img src="images/overflow.png" alt="TTML overflow style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the above example, the <code>tts:noWrap</code> is set to
 <code>noWrap</code> to prevent automatic line wrapping (breaking);
 if this were not specified, then overflow would occur in the block
-progression direction as opposed to the inline progression direction.</p></div></div><div class="div3">
-<h4><a name="style-attribute-padding" id="style-attribute-padding"/>8.2.16 tts:padding</h4><p>The <code>tts:padding</code> attribute is used to specify padding (or inset)
+progression direction as opposed to the inline progression direction.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.21.2.</p></div></div><div class="div3">
+<h4><a id="style-attribute-padding"></a>8.2.16 tts:padding</h4><p>The <code>tts:padding</code> attribute is used to specify padding (or inset)
 space on all sides of a region area.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-padding" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-padding"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <a href="#style-value-length">&lt;length&gt;</a> |
 <a href="#style-value-length">&lt;length&gt;</a> <a href="#style-value-length">&lt;length&gt;</a> |
 <a href="#style-value-length">&lt;length&gt;</a> <a href="#style-value-length">&lt;length&gt;</a> <a href="#style-value-length">&lt;length&gt;</a> |
@@ -2670,9 +2800,9 @@
 before edge, the second applies to the start and end edges, and the third applies
 to the after edge.
 If four <a href="#style-value-length">&lt;length&gt;</a> specifications are provided, then they apply to before, end,
-after, and start edges, respectively.</p><p>If a specified value of this attribute is not supported,
+after, and start edges, respectively.</p><p>The <a href="#style-value-length">&lt;length&gt;</a> value(s) used to express padding must be non-negative.</p><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>0px</code> were specified.</p><p>The <code>tts:padding</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-padding-example-1" class="example"><caption>Example Fragment – Padding</caption><tbody><tr><td>
+value <code>0px</code> were specified.</p><p>The <code>tts:padding</code> style is illustrated by the following example.</p><a id="style-attribute-padding-example-1"></a><table class="example"><caption>Example Fragment – Padding</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="446px 104px"/&gt;
@@ -2691,15 +2821,19 @@
 &lt;/p&gt;
 </pre></div>
 </td></tr></tbody></table><p>When rendering an area to which padding applies, the background color that
-applies to the area is rendered into the padded portion of the area.</p><table summary="HTML Table" id="style-attribute-padding-example-1-images" class="example-images"><caption>Example Rendition – Padding</caption><tbody><tr><td>
-<img src="images/padding.png" alt="TTML padding style property"/>
-</td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-showBackground" id="style-attribute-showBackground"/>8.2.17 tts:showBackground</h4><p>The <code>tts:showBackground</code> attribute is used to specify
+applies to the area is rendered into the padded portion of the area.</p><a id="style-attribute-padding-example-1-images"></a><table class="example-images"><caption>Example Rendition – Padding</caption><tbody><tr><td>
+<img src="images/padding.png" alt="TTML padding style property">
+</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.31.15, except that individual shorthand values map to writing
+mode relative padding values as defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.8.31, 7.8.32, 7.8.33, and 7.8.34.</p></div></div><div class="div3">
+<h4><a id="style-attribute-showBackground"></a>8.2.17 tts:showBackground</h4><p>The <code>tts:showBackground</code> attribute is used to specify
 constraints on when the background color of a region is intended to be
 presented.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-showBackground" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-showBackground"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>always</code> |
 <code>whenActive</code>
 </td></tr><tr><td><em>Initial:</em></td><td><code>always</code></td></tr><tr><td><em>Applies to:</em></td><td>
@@ -2708,9 +2842,9 @@
 background color of a region is always rendered when performing presentation
 processing on a visual medium; if the value is <code>whenActive</code>,
 then the background color of a region is rendered only when some
-content is selected into the region.</p><p>If a specified value of this attribute is not supported,
+content is flowed into the region.</p><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>always</code> were specified.</p><p>The <code>tts:showBackground</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-showBackground-example-1" class="example"><caption>Example Fragment – Show Background</caption><tbody><tr><td>
+value <code>always</code> were specified.</p><p>The <code>tts:showBackground</code> style is illustrated by the following example.</p><a id="style-attribute-showBackground-example-1"></a><table class="example"><caption>Example Fragment – Show Background</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:origin="0px 0px"/&gt;
@@ -2731,13 +2865,15 @@
   &lt;style <span class="strong">tts:showBackground="whenActive"</span>/&gt;
 &lt;/region&gt;
 </pre></div>
-</td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-textAlign" id="style-attribute-textAlign"/>8.2.18 tts:textAlign</h4><p>The <code>tts:textAlign</code> attribute is used to specify a style property that
+</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#smil21">[SMIL 2.1]</a>,
+§ 5.3.3.</p></div></div><div class="div3">
+<h4><a id="style-attribute-textAlign"></a>8.2.18 tts:textAlign</h4><p>The <code>tts:textAlign</code> attribute is used to specify a style property that
 defines how inline areas are aligned within a containing block area in the inline progression
 direction.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-textAlign" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-textAlign"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>left</code> |
 <code>center</code> |
 <code>right</code> |
@@ -2747,7 +2883,7 @@
 <a href="#content-vocabulary-p"><code>p</code></a>
 </td></tr><tr><td><em>Inherited:</em></td><td>yes</td></tr><tr><td><em>Percentages:</em></td><td>N/A</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>start</code> were specified.</p><p>The <code>tts:textAlign</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-textAlign-example-1" class="example"><caption>Example Fragment – Text Align</caption><tbody><tr><td>
+value <code>start</code> were specified.</p><p>The <code>tts:textAlign</code> style is illustrated by the following example.</p><a id="style-attribute-textAlign-example-1"></a><table class="example"><caption>Example Fragment – Text Align</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="355px 43px"/&gt;
@@ -2773,13 +2909,15 @@
   The frumious Bandersnatch!
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-textAlign-example-1-images" class="example-images"><caption>Example Rendition – Text Align</caption><tbody><tr><td><img src="images/textAlign.png" alt="TTML textAlign style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-textDecoration" id="style-attribute-textDecoration"/>8.2.19 tts:textDecoration</h4><p>The <code>tts:textDecoration</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-textAlign-example-1-images"></a><table class="example-images"><caption>Example Rendition – Text Align</caption><tbody><tr><td><img src="images/textAlign.png" alt="TTML textAlign style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.16.9.</p></div></div><div class="div3">
+<h4><a id="style-attribute-textDecoration"></a>8.2.19 tts:textDecoration</h4><p>The <code>tts:textDecoration</code> attribute is used to specify a style property that
 defines a text decoration effect to apply to glyph areas or other inline
 areas that are generated by content flowed into a region.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-textDecoration" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-textDecoration"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>none</code> |
 [ [
 <code>underline</code> |
@@ -2795,7 +2933,10 @@
 style property, each character child of a <code>p</code> element is
 considered to be enclosed in an anonymous span.</p><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>none</code> were specified.</p><p>The <code>tts:textDecoration</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-textDecoration-example-1" class="example"><caption>Example Fragment – Text Decoration</caption><tbody><tr><td>
+value <code>none</code> were specified.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The syntax used above in defining the value of this property is based on the
+value component syntax defined in <a href="#css2">[CSS2]</a>, § 1.4.2.1. In essence,
+one or more of the values separated by <code>||</code> may appear in the property
+value in any order, such as <code>"noUnderline overline lineThrough"</code>.</p></div><p>The <code>tts:textDecoration</code> style is illustrated by the following example.</p><a id="style-attribute-textDecoration-example-1"></a><table class="example"><caption>Example Fragment – Text Decoration</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="385px 82px"/&gt;
@@ -2818,13 +2959,15 @@
   &lt;/span&gt;
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-textDecoration-example-1-images" class="example-images"><caption>Example Rendition – Text Decoration</caption><tbody><tr><td><img src="images/textDecoration.png" alt="TTML textDecoration style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-textOutline" id="style-attribute-textOutline"/>8.2.20 tts:textOutline</h4><p>The <code>tts:textOutline</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-textDecoration-example-1-images"></a><table class="example-images"><caption>Example Rendition – Text Decoration</caption><tbody><tr><td><img src="images/textDecoration.png" alt="TTML textDecoration style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.17.4.</p></div></div><div class="div3">
+<h4><a id="style-attribute-textOutline"></a>8.2.20 tts:textOutline</h4><p>The <code>tts:textOutline</code> attribute is used to specify a style property that
 defines a text outline effect to apply to glyphs that are selected for glyph areas generated
 by content flowed into a region.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-textOutline" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-textOutline"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>none</code> |
 <a href="#style-value-color">&lt;color&gt;</a>?
 <a href="#style-value-length">&lt;length&gt;</a>
@@ -2838,10 +2981,16 @@
 present, then it denotes the outline color; if no <em>color</em> term is
 present, the computed value of the <code>tts:color</code> applies.  The first
 <em>length</em> term denotes the outline thickness and the second length
-term, if present, indicates the blur radius.</p><p>If a specified value of this attribute is not supported,
+term, if present, indicates the blur radius.</p><p>The <a href="#style-value-length">&lt;length&gt;</a> value(s) used to express thickness and blur radius must be non-negative.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>When a <a href="#style-value-length">&lt;length&gt;</a> expressed in
+cells is used in a <code>tts:textOutline</code> value,
+the cell's dimension in the block progression dimension applies.
+For example, if text outline thickness is specified as 0.1c, the cell resolution
+is 20 by 10, and the extent of the <em>Root Container Region</em> is 640 by 480, then the
+outline thickness will be a nominal 480 / 10 * 0.1 pixels, i.e., 4.8px,
+without taking into account rasterization effects.</p></div><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
 value <code>none</code> were specified.</p><p>The <code>tts:textOutline</code> style is illustrated by the following
-example.</p><table summary="HTML Table" id="style-attribute-textOutline-example-1" class="example"><caption>Example Fragment – Text Outline</caption><tbody><tr><td>
+example.</p><a id="style-attribute-textOutline-example-1"></a><table class="example"><caption>Example Fragment – Text Outline</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:backgroundColor="transparent"/&gt;
@@ -2862,13 +3011,13 @@
   With gently smiling jaws!
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-textOutline-example-1-images" class="example-images"><caption>Example Rendition – Text Outline</caption><tbody><tr><td><img src="images/textOutline.png" alt="backgroundColor style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-unicodeBidi" id="style-attribute-unicodeBidi"/>8.2.21 tts:unicodeBidi</h4><p>The <code>tts:unicodeBidi</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-textOutline-example-1-images"></a><table class="example-images"><caption>Example Rendition – Text Outline</caption><tbody><tr><td><img src="images/textOutline.png" alt="backgroundColor style property"></td></tr></tbody></table></div><div class="div3">
+<h4><a id="style-attribute-unicodeBidi"></a>8.2.21 tts:unicodeBidi</h4><p>The <code>tts:unicodeBidi</code> attribute is used to specify a style property that
 defines a directional embedding or override according to
 the Unicode bidirectional algorithm.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-unicodeBidi" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-unicodeBidi"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>normal</code> |
 <code>embed</code> |
 <code>bidiOverride</code>
@@ -2881,7 +3030,7 @@
 each character child of a <code>p</code> element is considered to be enclosed in an anonymous
 span.</p><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>normal</code> were specified.</p><p>The <code>tts:unicodeBidi</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-unicodeBidi-example-1" class="example"><caption>Example Fragment – Unicode Bidirectionality</caption><tbody><tr><td>
+value <code>normal</code> were specified.</p><p>The <code>tts:unicodeBidi</code> style is illustrated by the following example.</p><a id="style-attribute-unicodeBidi-example-1"></a><table class="example"><caption>Example Fragment – Unicode Bidirectionality</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="265px 84px"/&gt;
@@ -2898,15 +3047,17 @@
   &lt;span <span class="strong">tts:unicodeBidi="bidiOverride"</span> tts:direction="rtl"&gt;where the tourists snore.&lt;/span&gt;
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-unicodeBidi-example-1-images" class="example-images"><caption>Example Rendition – Unicode Bidirectionality</caption><tbody><tr><td>
-<img src="images/unicodeBidi.png" alt="TTML unicodeBidi style property"/>
-</td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-visibility" id="style-attribute-visibility"/>8.2.22 tts:visibility</h4><p>The <code>tts:visibility</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-unicodeBidi-example-1-images"></a><table class="example-images"><caption>Example Rendition – Unicode Bidirectionality</caption><tbody><tr><td>
+<img src="images/unicodeBidi.png" alt="TTML unicodeBidi style property">
+</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.29.6.</p></div></div><div class="div3">
+<h4><a id="style-attribute-visibility"></a>8.2.22 tts:visibility</h4><p>The <code>tts:visibility</code> attribute is used to specify a style property that
 defines whether generated areas are visible or not when rendered on a visual
 presentation medium.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-visibility" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-visibility"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>visible</code> |
 <code>hidden</code>
 </td></tr><tr><td><em>Initial:</em></td><td>
@@ -2922,7 +3073,7 @@
 span.</p><p>The <code>tts:visibility</code> style has no affect on content layout or
 composition, but merely determines whether composed content is visible or not.</p><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>visible</code> were specified.</p><p>The <code>tts:visibility</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-visibility-example-1" class="example"><caption>Example Fragment – Visibility</caption><tbody><tr><td>
+value <code>visible</code> were specified.</p><p>The <code>tts:visibility</code> style is illustrated by the following example.</p><a id="style-attribute-visibility-example-1"></a><table class="example"><caption>Example Fragment – Visibility</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="398px 121px"/&gt;
@@ -2946,21 +3097,23 @@
   &lt;/span&gt;
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-visibility-example-1-images" class="example-images"><caption>Example Rendition – Visibility</caption><tbody><tr><td>
-<img src="images/visibility_0.png" alt="TTML visibility style property - [0,1)"/>
-</td></tr><tr><td>
-<img src="images/visibility_1.png" alt="TTML visibility style property - [1,2)"/>
+</td></tr></tbody></table><p></p><a id="style-attribute-visibility-example-1-images"></a><table class="example-images"><caption>Example Rendition – Visibility</caption><tbody><tr><td>
+<img src="images/visibility_0.png" alt="TTML visibility style property - [0,1)">
 </td></tr><tr><td>
-<img src="images/visibility_2.png" alt="TTML visibility style property - [2,3)"/>
+<img src="images/visibility_1.png" alt="TTML visibility style property - [1,2)">
 </td></tr><tr><td>
-<img src="images/visibility_3.png" alt="TTML visibility style property - [3,4)"/>
-</td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-wrapOption" id="style-attribute-wrapOption"/>8.2.23 tts:wrapOption</h4><p>The <code>tts:wrapOption</code> attribute is used to specify a style property that
+<img src="images/visibility_2.png" alt="TTML visibility style property - [2,3)">
+</td></tr><tr><td>
+<img src="images/visibility_3.png" alt="TTML visibility style property - [3,4)">
+</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.30.17.</p></div></div><div class="div3">
+<h4><a id="style-attribute-wrapOption"></a>8.2.23 tts:wrapOption</h4><p>The <code>tts:wrapOption</code> attribute is used to specify a style property that
 defines whether or not automatic line wrapping (breaking) applies within the context of
 the affected element.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-wrapOption" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-wrapOption"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>wrap</code> |
 <code>noWrap</code>
 </td></tr><tr><td><em>Initial:</em></td><td><code>wrap</code></td></tr><tr><td><em>Applies to:</em></td><td>
@@ -2969,7 +3122,7 @@
 each character child of a <code>p</code> element is considered to be enclosed in an anonymous
 span.</p><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>wrap</code> were specified.</p><p>The <code>tts:wrapOption</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-wrapOption-example-1" class="example"><caption>Example Fragment – Wrap Option</caption><tbody><tr><td>
+value <code>wrap</code> were specified.</p><p>The <code>tts:wrapOption</code> style is illustrated by the following example.</p><a id="style-attribute-wrapOption-example-1"></a><table class="example"><caption>Example Fragment – Wrap Option</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="192px 117px"/&gt;
@@ -2987,13 +3140,15 @@
   A-sitting on a gate.
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-wrapOption-example-1-images" class="example-images"><caption>Example Rendition – Wrap Option</caption><tbody><tr><td><img src="images/wrapOption.png" alt="TTML wrapOption style property"/></td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-attribute-writingMode" id="style-attribute-writingMode"/>8.2.24 tts:writingMode</h4><p>The <code>tts:writingMode</code> attribute is used to specify a style property that
+</td></tr></tbody></table><p></p><a id="style-attribute-wrapOption-example-1-images"></a><table class="example-images"><caption>Example Rendition – Wrap Option</caption><tbody><tr><td><img src="images/wrapOption.png" alt="TTML wrapOption style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.16.13.</p></div></div><div class="div3">
+<h4><a id="style-attribute-writingMode"></a>8.2.24 tts:writingMode</h4><p>The <code>tts:writingMode</code> attribute is used to specify a style property that
 defines the block and inline progression directions to be used for the purpose of
 stacking block and inline areas within a region area.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-writingMode" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-writingMode"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>lrtb</code> |
 <code>rltb</code> |
 <code>tbrl</code> |
@@ -3005,7 +3160,7 @@
 <a href="#layout-vocabulary-region"><code>region</code></a>
 </td></tr><tr><td><em>Inherited:</em></td><td>no</td></tr><tr><td><em>Percentages:</em></td><td>N/A</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>lrtb</code> were specified.</p><p>The <code>tts:writingMode</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-writingMode-example-1" class="example"><caption>Example Fragment – Writing Mode</caption><tbody><tr><td>
+value <code>lrtb</code> were specified.</p><p>The <code>tts:writingMode</code> style is illustrated by the following example.</p><a id="style-attribute-writingMode-example-1"></a><table class="example"><caption>Example Fragment – Writing Mode</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:extent="50px 570px"/&gt;
@@ -3032,17 +3187,19 @@
   I sometimes search the grassy knolls for the wheels of Hansom-cabs.
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><table summary="HTML Table" id="style-attribute-writingMode-example-1-images" class="example-images"><caption>Example Rendition – Writing Mode</caption><tbody><tr><td><img src="images/writingMode.png" alt="TTML writingMode style property"/></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the second paragraph in the above example that targets region
+</td></tr></tbody></table><p></p><a id="style-attribute-writingMode-example-1-images"></a><table class="example-images"><caption>Example Rendition – Writing Mode</caption><tbody><tr><td><img src="images/writingMode.png" alt="TTML writingMode style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the second paragraph in the above example that targets region
 <code>r2</code>, the <code>tts:unicodeBidi</code> and
 <code>tts:direction</code> properties are set to
 <code>bidiOverride</code> and <code>rtl</code>, respectively, in order
 to override the normally left-to-right directionality of characters in
-the Latin script.</p></div></div><div class="div3">
-<h4><a name="style-attribute-zIndex" id="style-attribute-zIndex"/>8.2.25 tts:zIndex</h4><p>The <code>tts:zIndex</code> attribute is used to specify a style property that
+the Latin script.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.29.7.</p></div></div><div class="div3">
+<h4><a id="style-attribute-zIndex"></a>8.2.25 tts:zIndex</h4><p>The <code>tts:zIndex</code> attribute is used to specify a style property that
 defines the front-to-back ordering of region areas in the case that they overlap.</p><p>This attribute may be specified by any
 element type
 that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p><table summary="HTML Table" id="style-property-details-zIndex" class="common"><col width="25%" span="1"/><tbody><tr><td><em>Values:</em></td><td>
+as a style property only to those element types indicated in the following table.</p><a id="style-property-details-zIndex"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
 <code>auto</code> |
 <a href="#style-value-integer">&lt;integer&gt;</a>
 </td></tr><tr><td><em>Initial:</em></td><td><code>auto</code></td></tr><tr><td><em>Applies to:</em></td><td>
@@ -3050,12 +3207,11 @@
 </td></tr><tr><td><em>Inherited:</em></td><td>no</td></tr><tr><td><em>Percentages:</em></td><td>N/A</td></tr><tr><td><em>Animatable:</em></td><td>discrete</td></tr></tbody></table><p>If two areas are associated with the same Z-index value, then, if those areas
 overlap in space, the area(s) generated by lexically subsequent elements must be
 rendered over area(s) generated by lexically prior elements, where lexical
-order is defined as the postorder traversal of a document
-instance.</p><p>The semantics of the value <code>auto</code> are those defined by
+order is defined as the postorder traversal of a <em>Document Instance</em>.</p><p>The semantics of the value <code>auto</code> are those defined by
 <a href="#xsl11">[XSL 1.1]</a>, § 7.30.18, where the <code>tt</code> element
 is considered to establish the root stacking context.</p><p>If a specified value of this attribute is not supported,
 then a presentation processor must interpret the attribute as if the
-value <code>auto</code> were specified.</p><p>The <code>tts:zIndex</code> style is illustrated by the following example.</p><table summary="HTML Table" id="style-attribute-zIndex-example-1" class="example"><caption>Example Fragment – Z Index</caption><tbody><tr><td>
+value <code>auto</code> were specified.</p><p>The <code>tts:zIndex</code> style is illustrated by the following example.</p><a id="style-attribute-zIndex-example-1"></a><table class="example"><caption>Example Fragment – Z Index</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   &lt;style tts:origin="0px 0px"/&gt;
@@ -3110,28 +3266,33 @@
   And concluded the banquet by...
 &lt;/p&gt;
 </pre></div>
-</td></tr></tbody></table><p/><p/><table summary="HTML Table" id="style-attribute-zIndex-example-1-images" class="example-images"><caption>Example Rendition – Z Index</caption><tbody><tr><td><img src="images/zIndex.png" alt="TTML zIndex style property"/></td></tr></tbody></table></div></div><div class="div2">
-<h3><a name="styling-style-value-expressions" id="styling-style-value-expressions"/>8.3 Style Value Expressions</h3><p>Style property values include the use of the following expressions:</p><ul><li><p><a href="#style-value-alpha"><b>8.3.1 &lt;alpha&gt;</b></a></p></li><li><p><a href="#style-value-color"><b>8.3.2 &lt;color&gt;</b></a></p></li><li><p><a href="#style-value-digit"><b>8.3.3 &lt;digit&gt;</b></a></p></li><li><p><a href="#style-value-duration"><b>8.3.4 &lt;duration&gt;</b></a></p></li><li><p><a href="#style-value-familyName"><b>8.3.5 &lt;familyName&gt;</b></a></p></li><li><p><a href="#style-value-genericFamilyName"><b>8.3.6 &lt;genericFamilyName&gt;</b></a></p></li><li><p><a href="#style-value-hexDigit"><b>8.3.7 &lt;hexDigit&gt;</b></a></p></li><li><p><a href="#style-value-integer"><b>8.3.8 &lt;integer&gt;</b></a></p></li><li><p><a href="#style-value-length"><b>8.3.9 &lt;length&gt;</b></a></p></li><li><p><a href="#style-value-namedColor"><b>8.3.10 &lt;namedColor&gt;</b></a></p></li><li><p><a href="#style-value-quotedString"><b>8.3.11 &lt;quotedString&gt;</b></a></p></li><li><p><a href="#style-value-string"><b>8.3.12 &lt;string&gt;</b></a></p></li></ul><div class="div3">
-<h4><a name="style-value-alpha" id="style-value-alpha"/>8.3.1 &lt;alpha&gt;</h4><p>An &lt;alpha&gt; expression is used to express an opacity value,
-where	0 means fully transparent and 1 means fully opaque.</p><table summary="HTML Table" id="alpha-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;alpha&gt;</caption><tbody><tr><td>
+</td></tr></tbody></table><p></p><p></p><a id="style-attribute-zIndex-example-1-images"></a><table class="example-images"><caption>Example Rendition – Z Index</caption><tbody><tr><td><img src="images/zIndex.png" alt="TTML zIndex style property"></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the style property
+represented by this attribute are based upon that defined by <a href="#xsl11">[XSL 1.1]</a>,
+§ 7.30.18.</p></div></div></div><div class="div2">
+<h3><a id="styling-style-value-expressions"></a>8.3 Style Value Expressions</h3><p>Style property values include the use of the following expressions:</p><ul><li><p><a href="#style-value-alpha"><b>8.3.1 &lt;alpha&gt;</b></a></p></li><li><p><a href="#style-value-color"><b>8.3.2 &lt;color&gt;</b></a></p></li><li><p><a href="#style-value-digit"><b>8.3.3 &lt;digit&gt;</b></a></p></li><li><p><a href="#style-value-familyName"><b>8.3.5 &lt;familyName&gt;</b></a></p></li><li><p><a href="#style-value-genericFamilyName"><b>8.3.6 &lt;genericFamilyName&gt;</b></a></p></li><li><p><a href="#style-value-hexDigit"><b>8.3.7 &lt;hexDigit&gt;</b></a></p></li><li><p><a href="#style-value-integer"><b>8.3.8 &lt;integer&gt;</b></a></p></li><li><p><a href="#style-value-length"><b>8.3.9 &lt;length&gt;</b></a></p></li><li><p><a href="#style-value-namedColor"><b>8.3.10 &lt;namedColor&gt;</b></a></p></li></ul><p>In the syntax representations defined in this section, no
+linear whitespace (LWSP) is implied or permitted between tokens
+unless explicitly specified.</p><div class="div3">
+<h4><a id="style-value-alpha"></a>8.3.1 &lt;alpha&gt;</h4><p>An &lt;alpha&gt; expression is used to express an opacity value,
+where	0 means fully transparent and 1 means fully opaque.</p><a id="alpha-style-expression-syntax"></a><table class="syntax"><caption>Syntax Representation – &lt;alpha&gt;</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;alpha&gt;
   : <em>float</em>
 </pre></div>
 </td></tr></tbody></table><p>In the above syntax representation, the syntactic element
 <em><code>float</code></em> must adhere to the lexical
-representation defined by <a href="#xsd-2">[XML Schema Part 2]</a> §
+representation defined by <a href="#xsd-2">[XML Schema Part 2]</a>&nbsp;§
 3.2.4.1. If the value represented is less than 0.0,
 then it must be interpreted as equal to 0.0; similarly, if the value
 represented is greater than 1.0, then it must be interpreted as
-1.0. The value NaN shall be interpreted as 0.0.</p><p>If a presentation processor does not support a specific,
+1.0. The value NaN must be interpreted as 0.0.</p><p>A specified value for &lt;alpha&gt; should not be <code>NaN</code>,
+less than 0, or greater than 1.</p><p>If a presentation processor does not support a specific,
 valid opacity value, then it must interpret it as being equal to the
 closest supported value.</p></div><div class="div3">
-<h4><a name="style-value-color" id="style-value-color"/>8.3.2 &lt;color&gt;</h4><p>A &lt;color&gt; expression is used to specify a named color, exact RGB color triple,
+<h4><a id="style-value-color"></a>8.3.2 &lt;color&gt;</h4><p>A &lt;color&gt; expression is used to specify a named color, exact RGB color triple,
 or exact RGBA color tuple, where the alpha component, if expressed,
 is maximum (255) at 100% opacity
 and minimum (0) at 0% opacity, and where the applicable color space is
-defined by <a href="#srgb">[SRGB]</a>.</p><table summary="HTML Table" id="color-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;color&gt;</caption><tbody><tr><td>
+defined by <a href="#srgb">[SRGB]</a>.</p><a id="color-style-expression-syntax"></a><table class="syntax"><caption>Syntax Representation – &lt;color&gt;</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;color&gt;
   : "#" rrggbb
@@ -3167,43 +3328,84 @@
 used here to the YUV color space for rendition on a television device.</p></div><p>If a presentation processor does not support a specific,
 valid color or alpha value, then it must interpret it as being equal
 to the closest supported value.</p></div><div class="div3">
-<h4><a name="style-value-digit" id="style-value-digit"/>8.3.3 &lt;digit&gt;</h4><p>A &lt;digit&gt; is used to express integers and other types of numbers or tokens.</p><table summary="HTML Table" id="digit-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;digit&gt;</caption><tbody><tr><td>
+<h4><a id="style-value-digit"></a>8.3.3 &lt;digit&gt;</h4><p>A &lt;digit&gt; is used to express integers and other types of numbers or tokens.</p><a id="digit-style-expression-syntax"></a><table class="syntax"><caption>Syntax Representation – &lt;digit&gt;</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;digit&gt;
   : "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
 </pre></div>
 </td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-value-duration" id="style-value-duration"/>8.3.4 &lt;duration&gt;</h4><p>A &lt;duration&gt; expression is used to express a temporal duration value.</p><table summary="HTML Table" id="duration-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;duration&gt;</caption><tbody><tr><td>
-<div class="exampleInner"><pre>
-&lt;duration&gt;
-  : <a href="#style-value-digit">&lt;digit&gt;</a>+ ( "." <a href="#style-value-digit">&lt;digit&gt;</a>+ )? metric
-
-metric
-  : "s"                 // seconds
-  | "ms"                // milliseconds
-  | "f"                 // frames
-  | "t"                 // ticks
-</pre></div>
-</td></tr></tbody></table><p>It is an error to omit the metric component of a duration.</p><p>When operating with <code>smpte</code> time base and
-<code>discontinuous</code> mode, a duration expression must be
-considered to denote a duration in (local) real-time, independently of the
-governing time base.</p></div><div class="div3">
-<h4><a name="style-value-familyName" id="style-value-familyName"/>8.3.5 &lt;familyName&gt;</h4><p>A &lt;familyName&gt; expression specifies a font family name.</p><p>If the name contains a quotation delimiter character,
-then it must be expressed as a
-&lt;quotedString&gt;. If the name contains a
-whitespace character,
-then it should be expressed as a
-&lt;quotedString&gt;; however, if it is expressed as a &lt;string&gt;, then it
-must not contain a <code>COMMA</code> ',' character.</p><table summary="HTML Table" id="familyName-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;familyName&gt;</caption><tbody><tr><td>
+<h4><a id="style-value-duration"></a>8.3.4 Deleted</h4><div class="note"><p class="prefix"><b>Note:</b></p><p>The information from this section has been removed due to lack of any normative
+use within this specification. This section is retained in its empty form
+in order to prevent section renumbering.</p></div></div><div class="div3">
+<h4><a id="style-value-familyName"></a>8.3.5 &lt;familyName&gt;</h4><p>A &lt;familyName&gt; expression specifies a font family name.</p><a id="familyName-style-expression-syntax"></a><table class="syntax"><caption>Syntax Representation – &lt;familyName&gt;</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;familyName&gt;
-  : <a href="#style-value-string">&lt;string&gt;</a>
-  | <a href="#style-value-quotedString">&lt;quotedString&gt;</a>
+  : unquoted-string
+  | quoted-string
+
+unquoted-string
+  : identifier ( lwsp identifier )*
+
+lwsp
+  : ( ' ' | '\t' | '\n' | '\r' )+
+
+identifier
+  : [-]? identifier-start identifier-following*
+
+identifier-start
+  : [_a-zA-Z]
+  | non-ascii-or-c1
+  | escape
+
+identifier-following
+  : [_a-zA-Z0-9-]
+  | non-ascii-or-c1
+  | escape
+
+non-ascii-or-c1
+  : [^\0-\237]
+
+escape
+  : '\\' <em>char</em>
+
+quoted-string
+  : double-quoted-string
+  | single-quoted-string
+
+double-quoted-string
+  : '"' ( [^"\\] | escape )+ '"'
+
+single-quoted-string
+  : "'" ( [^'\\] | escape )+ "'"
 </pre></div>
-</td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-value-genericFamilyName" id="style-value-genericFamilyName"/>8.3.6 &lt;genericFamilyName&gt;</h4><p>A &lt;genericFamilyName&gt; expression specifies a font family using a general
+
+</td></tr></tbody></table><p>In addition to adhering to the syntax rules specified above, the following semantic rules apply:</p><ul><li><p>the semantic value of a &lt;familyName&gt; expression is the semantic value of its <code>unquoted-string</code> or <code>quoted-string</code>
+non-terminal, according to whichever applies;</p></li><li><p>the semantic value of an <code>unquoted-string</code> non-terminal is a pair <code>&lt;</code><em>quoted</em>, <em>content</em><code>&gt;</code>,
+where <em>quoted</em> is a boolean <code>false</code>, and
+where <em>content</em> is the result of appending the value of each <code>identifier</code>
+non-terminal, in lexical order, where the value of each identifier is preceded by a single SPACE (U+0020) character if it is not the first
+identifier;</p></li><li><p>the semantic value of a <code>quoted-string</code> non-terminal is a pair <code>&lt;</code><em>quoted</em>, <em>content</em><code>&gt;</code>,
+where <em>quoted</em> is a boolean <code>true</code>, and
+where <em>content</em> is the unquoted content of the quoted string, i.e., the sequence of characters between the delimiting quotes.</p></li><li><p>the semantic value of an <code>escape</code> non-terminal is the value of the escaped <code>char</code>;</p></li><li><p>a &lt;familyName&gt; that takes the form of an <code>unquoted-string</code> that contains an <code>identifier</code> that
+starts with two <code>-</code> HYPHEN-MINUS (U+002D) characters must be considered to be invalid;</p></li><li><p>a &lt;familyName&gt; that takes the form of an <code>unquoted-string</code> that contains a single <code>identifier</code> that
+matches (by case sensitive comparison) a &lt;genericFamilyName&gt; must be interpreted as that &lt;genericFamilyName&gt;;</p></li><li><p>a &lt;familyName&gt; that takes the form of a <code>quoted-string</code> whose content (unquoted value)
+matches (by case sensitive comparison) a &lt;genericFamilyName&gt; must not be interpreted as that &lt;genericFamilyName&gt;, but as
+the actual name of a non-generic font family.</p></li></ul><div class="note"><p class="prefix"><b>Note:</b></p><p>The syntactic element <em><code>char</code></em> is to be interpreted according
+to the <code>Char</code> production defined by <a href="#xml10">[XML 1.0]</a>&nbsp;§2.2.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>The <code>{unicode}</code> escape mechanism defined by <a href="#css2">[CSS2]</a>&nbsp;§4.1.1
+is not supported by this syntax; rather, authors are expected to either (1) directly encode the character
+using the document encoding or (2) use an XML character reference according to
+<a href="#xml10">[XML 1.0]</a>&nbsp;§4.1. When a syntactically significant character needs to be used
+without its normal syntactic interpretation, it may be be escaped using the backslash
+(reverse solidus) <code>escape</code> non-terminal specified above.</p><p>When using the backslash (reverse solidus) <code>escape</code> non-terminal, the above syntax does
+not place any restriction on what character may be escaped, e.g., <code>\\[\n\r\f0-9a-f]</code> are
+permitted. If one of these latter escapes appears in a &lt;familyName&gt; expression, then it will
+need to be converted to a <code>{unicode}</code> escape if it is to be used with a standard XSL-FO
+or CSS parser. In particular, a backslash followed by a newline is ignored by CSS, while it is not
+ignored by the above syntax. Such an unignored escaped newline would need to be represented using
+an equivalent <code>{unicode}</code> escape, such as <code>\a</code>, to order to express in CSS.</p></div></div><div class="div3">
+<h4><a id="style-value-genericFamilyName"></a>8.3.6 &lt;genericFamilyName&gt;</h4><p>A &lt;genericFamilyName&gt; expression specifies a font family using a general
 token that indicates a class of font families.</p><p>The resolution of a generic family name to a concrete font instance is considered to
-be implementation dependent, both in the case of content authoring and content interpretation.</p><table summary="HTML Table" id="genericFamilyName-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;genericFamilyName&gt;</caption><tbody><tr><td>
+be implementation dependent, both in the case of content authoring and content interpretation.</p><a id="genericFamilyName-style-expression-syntax"></a><table class="syntax"><caption>Syntax Representation – &lt;genericFamilyName&gt;</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;genericFamilyName&gt;
   : "default"
@@ -3223,11 +3425,11 @@
 or <code>monospaceSerif</code>. The generic family names <code>sansSerif</code>
 and <code>serif</code> are to be interpreted as equivalent to <code>proportionalSansSerif</code>
 and <code>proportionalSerif</code>, respectively.</p><p>If the generic family name <code>default</code> is specified (or implied by
-an initial value), then its typographic characteristics is considered to be implementation
+an initial value), then its typographic characteristics are considered to be implementation
 dependent; however, it is recommended that this default font family be mapped to
 an monospaced, sans-serif font.</p></div><div class="div3">
-<h4><a name="style-value-hexDigit" id="style-value-hexDigit"/>8.3.7 &lt;hexDigit&gt;</h4><p>A &lt;hexDigit&gt; is used to express integers and other types of numbers or tokens
-that employ base 16 arithmetic.</p><p>For the purpose of parsing, no distinction must be made between lower and upper case.</p><table summary="HTML Table" id="hexDigit-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;hexDigit&gt;</caption><tbody><tr><td>
+<h4><a id="style-value-hexDigit"></a>8.3.7 &lt;hexDigit&gt;</h4><p>A &lt;hexDigit&gt; is used to express integers and other types of numbers or tokens
+that employ base 16 arithmetic.</p><p>For the purpose of parsing, a distinction must not be made between lower and upper case.</p><a id="hexDigit-style-expression-syntax"></a><table class="syntax"><caption>Syntax Representation – &lt;hexDigit&gt;</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;hexDigit&gt;
   : <a href="#style-value-digit">&lt;digit&gt;</a>
@@ -3235,14 +3437,14 @@
   | "A" | "B" | "C" | "D" | "E" | "F"
 </pre></div>
 </td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-value-integer" id="style-value-integer"/>8.3.8 &lt;integer&gt;</h4><p>An &lt;integer&gt; expression is used to express an arbitrary, signed integral value.</p><table summary="HTML Table" id="integer-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;integer&gt;</caption><tbody><tr><td>
+<h4><a id="style-value-integer"></a>8.3.8 &lt;integer&gt;</h4><p>An &lt;integer&gt; expression is used to express an arbitrary, signed integral value.</p><a id="integer-style-expression-syntax"></a><table class="syntax"><caption>Syntax Representation – &lt;integer&gt;</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;integer&gt;
   : ( "+" | "-" )? <a href="#style-value-digit">&lt;digit&gt;</a>+
 </pre></div>
 </td></tr></tbody></table></div><div class="div3">
-<h4><a name="style-value-length" id="style-value-length"/>8.3.9 &lt;length&gt;</h4><p>A &lt;length&gt; expression is used to express either a coordinate component of point
-in a cartesian space or a distance between two points in a cartesian space.</p><table summary="HTML Table" id="length-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;length&gt;</caption><tbody><tr><td>
+<h4><a id="style-value-length"></a>8.3.9 &lt;length&gt;</h4><p>A &lt;length&gt; expression is used to express either a coordinate component of point
+in a cartesian space or a distance between two points in a cartesian space.</p><a id="length-style-expression-syntax"></a><table class="syntax"><caption>Syntax Representation – &lt;length&gt;</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;length&gt;
   : scalar
@@ -3288,8 +3490,8 @@
 direction and equal to the block progression dimension of the scaled
 font when used to specify lengths in the block progression direction.</p><p>The semantics of the unit of measure <code>c</code> (cell) are
 defined by the parameter <a href="#parameter-attribute-cellResolution"><b>6.2.1 ttp:cellResolution</b></a>.</p></div><div class="div3">
-<h4><a name="style-value-namedColor" id="style-value-namedColor"/>8.3.10 &lt;namedColor&gt;</h4><p>A &lt;namedColor&gt; is used to express an RGBA color with a convenient name, and where the applicable color space is
-defined by <a href="#srgb">[SRGB]</a>.</p><p>For the purpose of parsing, no distinction must be made between lower and upper case.</p><table summary="HTML Table" id="namedColor-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;namedColor&gt;</caption><tbody><tr><td>
+<h4><a id="style-value-namedColor"></a>8.3.10 &lt;namedColor&gt;</h4><p>A &lt;namedColor&gt; is used to express an RGBA color with a convenient name, and where the applicable color space is
+defined by <a href="#srgb">[SRGB]</a>.</p><p>For the purpose of parsing, a distinction must not be made between lower and upper case.</p><a id="namedColor-style-expression-syntax"></a><table class="syntax"><caption>Syntax Representation – &lt;namedColor&gt;</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;namedColor&gt;
   : "transparent"                           // #00000000
@@ -3314,48 +3516,34 @@
 </pre></div>
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>Except for <code>transparent</code>, the set of named colors specified above constitutes a proper
 subset of the set of named colors specified by <a href="#svg11">[SVG 1.1]</a>, § 4.2.</p></div></div><div class="div3">
-<h4><a name="style-value-quotedString" id="style-value-quotedString"/>8.3.11 &lt;quotedString&gt;</h4><p>A &lt;quotedString&gt; is used to express a delimited string that may contain
-a whitespace or a quotation delimiter character. Two types of quotation delimiters
-are provided in order to accommodate strings that contain the other delimiter.</p><table summary="HTML Table" id="quotedString-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;quotedString&gt;</caption><tbody><tr><td>
-<div class="exampleInner"><pre>
-&lt;quotedString&gt;
-  : "\"" ( <em>char</em> - { "\"" } )* "\""
-  | "\'" ( <em>char</em> - { "\'" } )* "\'"
-</pre></div>
-</td></tr></tbody></table><p>In the above syntax representation, the syntactic element <em><code>char</code></em> must adhere to production
-[2] <code>Char</code> as defined by <a href="#xml10">[XML 1.0]</a> §
-2.2.</p></div><div class="div3">
-<h4><a name="style-value-string" id="style-value-string"/>8.3.12 &lt;string&gt;</h4><p>A &lt;string&gt; expression consists of a sequence of characters where no character
-is a quotation delimiter character.</p><table summary="HTML Table" id="string-style-expression-syntax" class="syntax"><caption>Syntax Representation – &lt;string&gt;</caption><tbody><tr><td>
-<div class="exampleInner"><pre>
-&lt;string&gt;
-  : ( <em>char</em> - { "\"" | "\'" } )+
-</pre></div>
-</td></tr></tbody></table><p>In the above syntax representation, the syntactic element <em><code>char</code></em> must adhere to production
-[2] <code>Char</code> as defined by <a href="#xml10">[XML 1.0]</a> §
-2.2.</p></div></div><div class="div2">
-<h3><a name="semantics-style-resolution" id="semantics-style-resolution"/>8.4 Style Resolution</h3><p>This section defines the semantics of style resolution in terms of
+<h4><a id="style-value-quotedString"></a>8.3.11 Deleted</h4><div class="note"><p class="prefix"><b>Note:</b></p><p>The information from this section has been incorporated into
+<a href="#style-value-familyName"><b>8.3.5 &lt;familyName&gt;</b></a>. This section is retained in its empty form
+in order to prevent section renumbering.</p></div></div><div class="div3">
+<h4><a id="style-value-string"></a>8.3.12 Deleted</h4><div class="note"><p class="prefix"><b>Note:</b></p><p>The information from this section has been incorporated into
+<a href="#style-value-familyName"><b>8.3.5 &lt;familyName&gt;</b></a>. This section is retained in its empty form
+in order to prevent section renumbering.</p></div></div></div><div class="div2">
+<h3><a id="semantics-style-resolution"></a>8.4 Style Resolution</h3><p>This section defines the semantics of style resolution in terms of
 a standard processing model as follows:</p><ul><li><p><a href="#semantics-style-association"><b>8.4.1 Style Association</b></a></p></li><li><p><a href="#semantics-style-inheritance"><b>8.4.2 Style Inheritance</b></a></p></li><li><p><a href="#semantics-style-resolution-value-categories"><b>8.4.3 Style Resolution Value Categories</b></a></p></li><li><p><a href="#semantics-style-resolution-processing"><b>8.4.4 Style Resolution Processing</b></a></p></li></ul><p>Any implementation of this model is permitted provided that the
 externally observable results are consistent with the results produced
 by this model.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of style resolution employed here are based upon
 <a href="#xsl11">[XSL 1.1]</a>, § 5.</p></div><div class="div3">
-<h4><a name="semantics-style-association" id="semantics-style-association"/>8.4.1 Style Association</h4><p>Style association is a sub-process of <a href="#semantics-style-resolution-processing"><b>8.4.4 Style Resolution Processing</b></a> used to determine the
+<h4><a id="semantics-style-association"></a>8.4.1 Style Association</h4><p>Style association is a sub-process of <a href="#semantics-style-resolution-processing"><b>8.4.4 Style Resolution Processing</b></a> used to determine the
 specified style set of each content and
 layout element.</p><p>Style matter may be associated with content
  and layout matter in a number of ways:</p><ul><li><p><a href="#semantics-style-association-inline">inline styling</a></p></li><li><p><a href="#semantics-style-association-referential">referential styling</a></p></li><li><p><a href="#semantics-style-association-chained-referential">chained referential styling</a></p></li></ul><p>In addition to the above, style matter may be associated with layout matter using:</p><ul><li><p><a href="#semantics-style-association-nested">nested styling</a></p></li></ul><div class="div4">
-<h5><a name="semantics-style-association-inline" id="semantics-style-association-inline"/>8.4.1.1 Inline Styling</h5><p>Style properties may be expressed in an inline manner by direct
+<h5><a id="semantics-style-association-inline"></a>8.4.1.1 Inline Styling</h5><p>Style properties may be expressed in an inline manner by direct
 specification of an attribute from the TT Style Namespace on the
 affected element. When expressed in this manner, the association of
 style information is referred to as <em>inline styling</em>.</p><p>Style properties associated by inline styling are afforded a higher priority than all other
-forms of style association.</p><table summary="HTML Table" id="style-association-example-1" class="example"><caption>Example – Inline Styling</caption><tbody><tr><td>
+forms of style association.</p><a id="style-association-example-1"></a><table class="example"><caption>Example – Inline Styling</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
-&lt;p <span class="strong">tts:color="white"</span>&gt;White 1 &lt;span <span class="strong">tts:color="yellow"</span>&gt;Yellow&lt;/span&gt; White 2&lt;/p&gt;
+&lt;p <span class="strong">tts:color="white"</span>&gt;White 1&nbsp;&lt;span <span class="strong">tts:color="yellow"</span>&gt;Yellow&lt;/span&gt;&nbsp;White 2&lt;/p&gt;
 </pre></div>
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the above example, the two text fragments <code>"White 1 "</code> and
 <code>" White 2"</code>, which are interpreted as anonymous spans, are not
 associated with a color style property; rather, they inherit their color style
 from their parent <code>p</code> element as described in <a href="#semantics-style-inheritance-content"><b>8.4.2.1 Content Style Inheritance</b></a> below.  </p></div></div><div class="div4">
-<h5><a name="semantics-style-association-referential" id="semantics-style-association-referential"/>8.4.1.2 Referential Styling</h5><p>Style properties may be expressed in an out-of-line manner and referenced by the
+<h5><a id="semantics-style-association-referential"></a>8.4.1.2 Referential Styling</h5><p>Style properties may be expressed in an out-of-line manner and referenced by the
 affected element using the <code>style</code> attribute. When expressed in this manner,
 the association of style information is referred to as <em>referential styling</em>.</p><p>If a <code>style</code> attribute specifies multiple references, then those references are
 evaluated in the specified order, and that order applies to resolution of the value of a
@@ -3365,37 +3553,29 @@
 element that is a descendant of a <code>layout</code> element.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The use of referential styling encourages the reuse of style specifications while
 sacrificing locality of reference.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>A single content element may be associated with style properties by a hybrid mixture of
 inline and referential styling, in which case inline styling is given priority as described above
-by <a href="#semantics-style-association-inline"><b>8.4.1.1 Inline Styling</b></a>.</p></div><table summary="HTML Table" id="style-association-example-2" class="example"><caption>Example – Referential Styling</caption><tbody><tr><td>
+by <a href="#semantics-style-association-inline"><b>8.4.1.1 Inline Styling</b></a>.</p></div><a id="style-association-example-2"></a><table class="example"><caption>Example – Referential Styling</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;style <span class="strong">xml:id="s1"</span> tts:color="white"/&gt;
 &lt;style <span class="strong">xml:id="s2"</span> tts:color="yellow"/&gt;
 ...
-&lt;p <span class="strong">style="s1"</span>&gt;White 1 &lt;span <span class="strong">style="s2"</span>&gt;Yellow&lt;/span&gt; White 2&lt;/p&gt;
+&lt;p <span class="strong">style="s1"</span>&gt;White 1&nbsp;&lt;span <span class="strong">style="s2"</span>&gt;Yellow&lt;/span&gt;&nbsp;White 2&lt;/p&gt;
 </pre></div>
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the above example, the two text fragments <code>"White 1 "</code> and
 <code>" White 2"</code>, which are interpreted as anonymous spans, are not
 associated with a color style property; rather, they inherit their color style
 from their parent <code>p</code> element as described in <a href="#semantics-style-inheritance-content"><b>8.4.2.1 Content Style Inheritance</b></a> below.</p></div></div><div class="div4">
-<h5><a name="semantics-style-association-chained-referential" id="semantics-style-association-chained-referential"/>8.4.1.3 Chained Referential Styling</h5><p>Style properties may be expressed in an out-of-line manner and may themselves reference
+<h5><a id="semantics-style-association-chained-referential"></a>8.4.1.3 Chained Referential Styling</h5><p>Style properties may be expressed in an out-of-line manner and may themselves reference
 other out-of-line style properties, thus creating a chain of references starting at the
 affected element. When expressed in this manner, the association of style information
 is referred to as <em>chained referential styling</em>.</p><p>If the same style property is specified in more than one referenced
-style 
-set,
-then the last referenced style
-set
-applies, where the order of application starts from
-the affected element and proceeds to referenced style
-sets,
-and, in turn, to subsequent, recursively
-referenced style
-sets.</p><p>A loop in a sequence of chained style references must be considered an error.</p><p>The use of referential styling is restricted to making
+style set, then the last referenced style set applies, where the order of application starts from
+the affected element and proceeds to referenced style sets, and, in turn, to subsequent referenced style sets.</p><p>A loop in a sequence of chained style references must be considered an error.</p><p>The use of referential styling is restricted to making
 reference to <code>style</code> element descendants of a <code>styling</code>
 element. It is considered an error to reference a <code>style</code>
 element that is a descendant of a <code>layout</code> element.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The use of chained referential styling encourages the grouping of style specifications
 into general and specific sets, which further aids in style specification reuse.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>A single content element may be associated with style properties by a hybrid mixture of
 inline, referential styling, and chained referential styling, in which case inline styling is
-given priority as described above by <a href="#semantics-style-association-inline"><b>8.4.1.1 Inline Styling</b></a>.</p></div><table summary="HTML Table" id="style-association-example-3" class="example"><caption>Example – Chained Referential Styling</caption><tbody><tr><td>
+given priority as described above by <a href="#semantics-style-association-inline"><b>8.4.1.1 Inline Styling</b></a>.</p></div><a id="style-association-example-3"></a><table class="example"><caption>Example – Chained Referential Styling</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;style <span class="strong">xml:id="s1"</span> tts:color="white" tts:fontFamily="monospaceSerif"/&gt;
 &lt;style <span class="strong">xml:id="s2"</span> <span class="strong">style="s1"</span> tts:color="yellow"/&gt;
@@ -3404,11 +3584,11 @@
 &lt;p <span class="strong">style="s2"</span>&gt;Yellow Monospace&lt;/p&gt;
 </pre></div>
 </td></tr></tbody></table></div><div class="div4">
-<h5><a name="semantics-style-association-nested" id="semantics-style-association-nested"/>8.4.1.4 Nested Styling</h5><p>Style properties may be expressed in an nested manner by direct specification of one or
+<h5><a id="semantics-style-association-nested"></a>8.4.1.4 Nested Styling</h5><p>Style properties may be expressed in a nested manner by direct specification of one or
 more <code>style</code> element children of the affected element.
 When expressed in this manner, the association of style information
 is referred to as <em>nested styling</em>.</p><p>Style properties associated by nested styling are afforded a lower priority than inline
-styling but with higher priority than referential styling.</p><table summary="HTML Table" id="style-association-example-4" class="example"><caption>Example – Nested Styling</caption><tbody><tr><td>
+styling but with higher priority than referential styling.</p><a id="style-association-example-4"></a><table class="example"><caption>Example – Nested Styling</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region xml:id="r1"&gt;
   <span class="strong">&lt;style tts:extent="128px 66px"/&gt;</span>
@@ -3418,16 +3598,16 @@
 </pre></div>
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In this version of this specification, nested styling applies only
 to the <code>region</code> element.</p></div></div></div><div class="div3">
-<h4><a name="semantics-style-inheritance" id="semantics-style-inheritance"/>8.4.2 Style Inheritance</h4><p>Style inheritance is a sub-process of <a href="#semantics-style-resolution-processing"><b>8.4.4 Style Resolution Processing</b></a> used to determine the
+<h4><a id="semantics-style-inheritance"></a>8.4.2 Style Inheritance</h4><p>Style inheritance is a sub-process of <a href="#semantics-style-resolution-processing"><b>8.4.4 Style Resolution Processing</b></a> used to determine the
 specified style set of each content and
 layout element.</p><p>Styles are further propagated to content matter
 using:
 </p><ul><li><p><a href="#semantics-style-inheritance-content">content style inheritance</a></p></li><li><p><a href="#semantics-style-inheritance-content">region style inheritance</a></p></li></ul><p>For the purpose of determining inherited styles, the element hierarchy of
-an intermediate synchronic document form of a TTML document instance must be used, where
+an intermediate synchronic document form of a <em>Document Instance</em> must be used, where
 such intermediate forms are defined by <a href="#semantics-region-layout-step-1"><b>9.3.2 Intermediate Synchronic Document Construction</b></a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The intermediate synchronic document form is utilized rather than
 the original form in order to facilitate region inheritance
 processing.</p></div><div class="div4">
-<h5><a name="semantics-style-inheritance-content" id="semantics-style-inheritance-content"/>8.4.2.1 Content Style Inheritance</h5><p>Style properties are inherited from ancestor content elements
+<h5><a id="semantics-style-inheritance-content"></a>8.4.2.1 Content Style Inheritance</h5><p>Style properties are inherited from ancestor content elements
 within an intermediate synchronic document
 if a style property is not associated with a content element (or
 an anonymous span) and the style property is designated as
@@ -3435,7 +3615,7 @@
 be the value of the same named style property in the computed
 style set of the
 element's immediate ancestor element
-within the applicable intermediate synchronic document.</p><table summary="HTML Table" id="style-inheritance-example-2" class="example"><caption>Example – Content Style Inheritance</caption><tbody><tr><td>
+within the applicable intermediate synchronic document.</p><a id="style-inheritance-example-2"></a><table class="example"><caption>Example – Content Style Inheritance</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;p <span class="strong">tts:fontFamily="monospaceSansSerif"</span>&gt;
   &lt;span tts:color="yellow"&gt;Yellow Monospace&lt;/span&gt;
@@ -3451,7 +3631,7 @@
 specified
 style
 set of the <code>span</code> element.</p></div></div><div class="div4">
-<h5><a name="semantics-style-inheritance-region" id="semantics-style-inheritance-region"/>8.4.2.2 Region Style Inheritance</h5><p>Style properties are inherited from a region element in the following case:</p><ol class="enumar"><li><p>if a style property <em>P</em> is not associated with
+<h5><a id="semantics-style-inheritance-region"></a>8.4.2.2 Region Style Inheritance</h5><p>Style properties are inherited from a region element in the following case:</p><ol class="enumar"><li><p>if a style property <em>P</em> is not associated with
 a content
 element or an anonymous span <em>E</em> and the style
 property is designated as inheritable, and</p></li><li><p>if that
@@ -3459,11 +3639,11 @@
 set of region
 <em>R</em>,
 and</p></li><li><p>if that element <em>E</em> is flowed into (presented within) region
-<em>R</em>.</p></li></ol><table summary="HTML Table" id="style-inheritance-example-3" class="example"><caption>Example – Region Style Inheritance</caption><tbody><tr><td>
+<em>R</em>.</p></li></ol><a id="style-inheritance-example-3"></a><table class="example"><caption>Example – Region Style Inheritance</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region <span class="strong">xml:id="r1"</span>&gt;
-  &lt;style tts:color="yellow"/&gt;
-  &lt;style tts:fontFamily="monospaceSerif"/&gt;
+&nbsp;&nbsp;&lt;style tts:color="yellow"/&gt;
+&nbsp;&nbsp;&lt;style tts:fontFamily="monospaceSerif"/&gt;
 &lt;/region&gt;
 ...
 &lt;p <span class="strong">region="r1"</span>&gt;Yellow Monospace&lt;/p&gt;
@@ -3472,14 +3652,14 @@
 items <code>Yellow Monospace</code> effectively inherits the <code>tts:color</code>
 and <code>tts:fontFamily</code> styles specified on the <code>region</code>
 element into which the <code>p</code> element is flowed (presented).</p></div></div></div><div class="div3">
-<h4><a name="semantics-style-resolution-value-categories" id="semantics-style-resolution-value-categories"/>8.4.3 Style Resolution Value Categories</h4><p>During style resolution, layout, and presentation processing,
+<h4><a id="semantics-style-resolution-value-categories"></a>8.4.3 Style Resolution Value Categories</h4><p>During style resolution, layout, and presentation processing,
 three categories of style property values are distinguished as
 follows:</p><ul><li><p><a href="#semantics-style-resolved-value-category-specified">specified values</a></p></li><li><p><a href="#semantics-style-resolved-value-category-computed">computed values</a></p></li><li><p><a href="#semantics-style-resolved-value-category-actual">actual values</a></p></li></ul><div class="div4">
-<h5><a name="semantics-style-resolved-value-category-specified" id="semantics-style-resolved-value-category-specified"/>8.4.3.1 Specified Values</h5><p>Values of style properties that are associated with or inherited
+<h5><a id="semantics-style-resolved-value-category-specified"></a>8.4.3.1 Specified Values</h5><p>Values of style properties that are associated with or inherited
 by an element or anonymous span are referred to as <em>specified values</em>. The
 set of all specified style properties of a given element is referred to
 as the <em>specified style set</em> of that element.</p></div><div class="div4">
-<h5><a name="semantics-style-resolved-value-category-computed" id="semantics-style-resolved-value-category-computed"/>8.4.3.2 Computed Values</h5><p>When style properties are specified using relative value expressions,
+<h5><a id="semantics-style-resolved-value-category-computed"></a>8.4.3.2 Computed Values</h5><p>When style properties are specified using relative value expressions,
 such as a named color, a relative unit (e.g., cell), or a percentage, then
 they need to be further resolved into absolute units, such as an RGB triple,
 pixels, etc.</p><p>During the style resolution process, all specified style values are
@@ -3492,7 +3672,7 @@
 such as percentage, require evaluating the expression in the immediate
 (local) context of reference, and not in a distant (remote) context of
 reference where the related (resolving) expression is not available.</p></div><div class="div4">
-<h5><a name="semantics-style-resolved-value-category-actual" id="semantics-style-resolved-value-category-actual"/>8.4.3.3 Actual Values</h5><p>During the actual presentation process, other transformations occur
+<h5><a id="semantics-style-resolved-value-category-actual"></a>8.4.3.3 Actual Values</h5><p>During the actual presentation process, other transformations occur
 that map some value expressions to concrete, physical values. For example,
 the colors of computed style values are further subjected to closest color
 approximation and gamma correction
@@ -3512,28 +3692,28 @@
 to actual style set values; as a consequence, no further use or reference
 to actual values is made below when formally describing the style
 resolution process.</p></div></div></div><div class="div3">
-<h4><a name="semantics-style-resolution-processing" id="semantics-style-resolution-processing"/>8.4.4 Style Resolution Processing</h4><p>The process of style resolution is defined herein as the procedure
+<h4><a id="semantics-style-resolution-processing"></a>8.4.4 Style Resolution Processing</h4><p>The process of style resolution is defined herein as the procedure
 (and results thereof) for resolving (determining) the computed values
 of all style properties that apply to content and layout elements:</p><ul><li><p><a href="#semantics-style-resolution-processing-definitions"><b>8.4.4.1 Conceptual Definitions</b></a></p></li><li><p><a href="#semantics-style-resolution-processing-sss"><b>8.4.4.2 Specified Style Set Processing</b></a></p></li><li><p><a href="#semantics-style-resolution-processing-css"><b>8.4.4.3 Computed Style Set Processing</b></a></p></li><li><p><a href="#semantics-style-resolution-process-overall"><b>8.4.4.4 Style Resolution Process</b></a></p></li></ul><p>The process described here forms an integral sub-process of
 <a href="#semantics-region-layout"><b>9.3 Region Layout and Presentation</b></a>.</p><div class="div4">
-<h5><a name="semantics-style-resolution-processing-definitions" id="semantics-style-resolution-processing-definitions"/>8.4.4.1 Conceptual Definitions</h5><p>For the purpose of interpreting the style resolution processing
+<h5><a id="semantics-style-resolution-processing-definitions"></a>8.4.4.1 Conceptual Definitions</h5><p>For the purpose of interpreting the style resolution processing
 model specified below, the following conceptual definitions apply:</p><dl><dt class="label">[style property]</dt><dd><p>a style property, <em>P</em>, is considered to consist of a
 tuple <code>[name, value]</code>, where the name of the
 property is a tuple <code>[namespace value,
 unqualified name]</code> and the value of the property is a
-tuple <code>[category, type, value expression]</code></p><table summary="HTML Table" id="conceptual-definition-example-style-property" class="example"><caption>Example – conceptual style property</caption><tbody><tr><td>
+tuple <code>[category, type, value expression]</code></p><a id="conceptual-definition-example-style-property"></a><table class="example"><caption>Example – conceptual style property</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 [
   ["http://www.w3.org/ns/ttml#styling", "color"],
   ["specified", <em>color</em>, "red"]
 ]
 </pre></div>
-</td></tr></tbody></table><p/></dd><dt class="label">[style (property) set]</dt><dd><p>a style (property) set consists of an unordered collection of style
+</td></tr></tbody></table><p></p></dd><dt class="label">[style (property) set]</dt><dd><p>a style (property) set consists of an unordered collection of style
 properties, where no two style properties within the set have an
 identical name, where by "identical name" is meant equality of
 namespace value of name tuple and unqualified name of name tuple;</p><p>in a specified style (property) set, the category of each style
 property is "specified"; a specified style (property) set of an
-element <em>E</em> is referred to as <em>SSS(E)</em>;</p><table summary="HTML Table" id="conceptual-definition-example-specified-style-set" class="example"><caption>Example – conceptual (specified) style (property) set</caption><tbody><tr><td>
+element <em>E</em> is referred to as <em>SSS(E)</em>;</p><a id="conceptual-definition-example-specified-style-set"></a><table class="example"><caption>Example – conceptual (specified) style (property) set</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 {
   [
@@ -3556,7 +3736,7 @@
 </pre></div>
 </td></tr></tbody></table><p>in a computed style (property) set, the category of each style
 property is either "specified" or "computed"; a computed style (property) set of an element
-<em>E</em> is referred to as <em>CSS(E)</em>;</p><table summary="HTML Table" id="conceptual-definition-example-computed-style-set" class="example"><caption>Example – conceptual (computed) style (property) set</caption><tbody><tr><td>
+<em>E</em> is referred to as <em>CSS(E)</em>;</p><a id="conceptual-definition-example-computed-style-set"></a><table class="example"><caption>Example – conceptual (computed) style (property) set</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 {
   [
@@ -3577,7 +3757,7 @@
   ]
 }
 </pre></div>
-</td></tr></tbody></table><p/></dd><dt class="label">[style (property) merging]</dt><dd><p>a style property <em>P<sub>new</sub></em> is merged into a
+</td></tr></tbody></table><p></p></dd><dt class="label">[style (property) merging]</dt><dd><p>a style property <em>P<sub>new</sub></em> is merged into a
 style (property) set, <em>SS</em>, as follows: if a style property
 <em>P<sub>old</sub></em> is already present in <em>SS</em>
 where the name of <em>P<sub>new</sub></em> is identical to the
@@ -3589,7 +3769,7 @@
 follows: for each style property <em>P<sub>new</sub></em> in
 <em>SS<sub>new</sub></em>, merge <em>P<sub>new</sub></em> into
 <em>SS<sub>old</sub></em>;</p></dd></dl></div><div class="div4">
-<h5><a name="semantics-style-resolution-processing-sss" id="semantics-style-resolution-processing-sss"/>8.4.4.2 Specified Style Set Processing</h5><p>The specified style set <em>SSS</em> of an element or
+<h5><a id="semantics-style-resolution-processing-sss"></a>8.4.4.2 Specified Style Set Processing</h5><p>The specified style set <em>SSS</em> of an element or
 anonymous span <em>E</em>,
 <em>SSS(E)</em>, is determined according to the following ordered
 rules:</p><ol class="enumar"><li><p><span class="strong">[initialization]</span> initialize
@@ -3612,6 +3792,10 @@
 style property <em>P</em> expressed as a specified styling
 attribute of <em>E</em>,
 merge <em>P</em> into the specified style
+set of <em>E</em>, <em>SSS(E)</em>;</p></li><li><p><span class="strong">[animation styling]</span> for each
+style property <em>P</em> expressed as a specified styling
+attribute of an immediate animation (<code>set</code>) element child of element <em>E</em>,
+merge <em>P</em> into the specified style
 set of <em>E</em>, <em>SSS(E)</em>;</p></li><li><p><span class="strong">[implicit inheritance]</span> if the
 element type of <em>E</em> is not the styling element type
 <code>style</code>, then for each inheritable style property
@@ -3630,7 +3814,7 @@
 <em>CSS(PARENT(E))</em>;</p></li><li><p>if the value of <em>P′</em> is not undefined, then merge
 <em>P′</em> into the specified style set of <em>E</em>,
 <em>SSS(E)</em>.</p></li></ol></li></ol></div><div class="div4">
-<h5><a name="semantics-style-resolution-processing-css" id="semantics-style-resolution-processing-css"/>8.4.4.3 Computed Style Set Processing</h5><p>The computed style set <em>CSS</em> of an element or
+<h5><a id="semantics-style-resolution-processing-css"></a>8.4.4.3 Computed Style Set Processing</h5><p>The computed style set <em>CSS</em> of an element or
 anonymous span <em>E</em>,
 <em>CSS(E)</em>, is determined according to the following ordered
 rules:</p><ol class="enumar"><li><p><span class="strong">[resolve specified styles]</span>
@@ -3653,7 +3837,7 @@
 context of a layout or content element which has a presentation
 context, and not in the non-presentation, declaration context
 of a referentiable <code>style</code> element.</p></div></div><div class="div4">
-<h5><a name="semantics-style-resolution-process-overall" id="semantics-style-resolution-process-overall"/>8.4.4.4 Style Resolution Process</h5><p>The top-level style resolution process is defined as follows: using
+<h5><a id="semantics-style-resolution-process-overall"></a>8.4.4.4 Style Resolution Process</h5><p>The top-level style resolution process is defined as follows: using
 a preorder traversal of each element and anonymous span,
 <em>E</em>, of an intermediate synchronic document,
 <em>DOC<sub>inter</sub></em>, perform the following ordered
@@ -3666,7 +3850,7 @@
 determine (obtain) the computed style set <em>CSS</em> of
 <em>E</em>, namely, <em>CSS(E)</em>, in accordance with
 <a href="#semantics-style-resolution-processing-css"><b>8.4.4.3 Computed Style Set Processing</b></a>.</p></li></ol></div></div></div></div><div class="div1">
-<h2><a name="layout" id="layout"/>9 Layout</h2><p>This section specifies the <em>layout</em> matter of the core
+<h2><a id="layout"></a>9 Layout</h2><p>This section specifies the <em>layout</em> matter of the core
 vocabulary catalog, where
 layout is to be understood as a separable layer of information that applies to
 content and that denotes authorial intentions about the presentation of
@@ -3678,12 +3862,12 @@
 exists – use of referential styling –
 in which the style
 matter is not embedded (inlined).</p></div><div class="div2">
-<h3><a name="layout-element-vocabulary" id="layout-element-vocabulary"/>9.1 Layout Element Vocabulary</h3><p>The following elements specify the structure and principal layout aspects of a
-document instance:</p><ul><li><p><a href="#layout-vocabulary-layout"><b>9.1.1 layout</b></a></p></li><li><p><a href="#layout-vocabulary-region"><b>9.1.2 region</b></a></p></li></ul><div class="div3">
-<h4><a name="layout-vocabulary-layout" id="layout-vocabulary-layout"/>9.1.1 layout</h4><p>The <code>layout</code> element is a container element used to group
+<h3><a id="layout-element-vocabulary"></a>9.1 Layout Element Vocabulary</h3><p>The following elements specify the structure and principal layout aspects of a
+<em>Document Instance</em>:</p><ul><li><p><a href="#layout-vocabulary-layout"><b>9.1.1 layout</b></a></p></li><li><p><a href="#layout-vocabulary-region"><b>9.1.2 region</b></a></p></li></ul><div class="div3">
+<h4><a id="layout-vocabulary-layout"></a>9.1.1 layout</h4><p>The <code>layout</code> element is a container element used to group
 layout matter, including metadata that applies to layout matter.</p><p>The <code>layout</code> element accepts as its children zero or more
 elements in the <code>Metadata.class</code> element group, followed by
-zero or more <code>region</code> elements.</p><table summary="HTML Table" id="elt-syntax-layout" class="syntax"><caption>XML Representation – Element Information Item: layout</caption><tbody><tr><td>
+zero or more <code>region</code> elements.</p><a id="elt-syntax-layout"></a><table class="syntax"><caption>XML Representation – Element Information Item: layout</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;layout
   <a href="#content-attribute-id">xml:id</a> = ID
@@ -3695,8 +3879,8 @@
 </pre></div>
 </td></tr></tbody></table><p>To the extent that time semantics apply to the content of the
 <code>layout</code> element, the implied time interval of this element is
-defined to be coterminous with the external time interval.</p></div><div class="div3">
-<h4><a name="layout-vocabulary-region" id="layout-vocabulary-region"/>9.1.2 region</h4><p>The <code>region</code> element is used to define a space or area into which content is
+defined to be coterminous with the <em>Root Temporal Extent</em>.</p></div><div class="div3">
+<h4><a id="layout-vocabulary-region"></a>9.1.2 region</h4><p>The <code>region</code> element is used to define a rectangular space or area into which content is
 to be flowed for the purpose of presentation.</p><p>In addition, and in accordance with
 <a href="#semantics-style-inheritance-region"><b>8.4.2.2 Region Style Inheritance</b></a>, 
 the <code>region</code> element may be used to specify inheritable style properties to be
@@ -3711,7 +3895,8 @@
 element group apply semantically to the <code>region</code> element.
 Any <code>style</code> child element must be considered a local style
 definition that applies only to the containing <code>region</code>
-element, i.e., does not apply for resolving referential styling.</p><table summary="HTML Table" id="elt-syntax-region" class="syntax"><caption>XML Representation – Element Information Item: region</caption><tbody><tr><td>
+element, i.e., does not apply for resolving referential styling (but does apply for region
+style inheritance).</p><a id="elt-syntax-region"></a><table class="syntax"><caption>XML Representation – Element Information Item: region</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;region
   <a href="#timing-attribute-begin">begin</a> = <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>
@@ -3735,54 +3920,54 @@
 If specified, these begin and end points are relative to the time
 interval of the nearest ancestor element associated with a time
 interval, irregardless of whether that interval is explicit or implied.</p><p>The nearest ancestor element of a <code>region</code> element that is associated
-with a time interval is the document instance's root <code>tt</code> element.</p><p>If a <code>dur</code> attribute is specified on the <code>region</code> element, then it
+with a time interval is the <code>layout</code> element.</p><p>If a <code>dur</code> attribute is specified on the <code>region</code> element, then it
 specifies the simple duration of the region.</p><p>For the purpose of determining the semantics of presentation processing, a
 region that is temporally inactive must not produce any visible marks when
 presented on a visual medium.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>A <code>region</code> element may be associated with a time interval for two
 purposes: (1) in order to temporally bound the presentation of the region and
 its content, and (2) to provide a temporal context in which animations of region
-styles may be effected.</p><p>For example, an author may wish a region that is otherwise empty, but
+styles may be effected.</p><p>For example, an author may wish to specify a region that is otherwise empty, but
 may have a visible background color to be presented starting at some time and
 continuing over the region's duration.  The simple duration of the region serves
 additionally to scope the presentation effects of content that is targeted to the
-region. An author may also wish to move a region within the root container
-extent or change a region's background color by means of animation effects. In
+region. An author may also wish to move a region within the <em>Root Container Region</em>
+or change a region's background color by means of animation effects. In
 both of these cases, it is necessary to posit an active time interval for a
 region.</p></div><p>If no <code>timeContainer</code> attribute is specified on
 a <code>region</code> element, then it must be interpreted as having
 <em>parallel</em> time containment semantics.</p><p>If a <a href="#metadata-attribute-role"><code>ttm:role</code></a> attribute is
 specified on a <code>region</code> element, then it must adhere to the
-value syntax defined by <a href="#metadata-attribute-role-syntax"><b>Syntax Representation – ttm:role</b></a>, and where the role(s) identified
-by this attribute expresses the semantic role(s) of the region
-independently from the semantic role(s) of any content targeted to
+value syntax defined by <a href="#metadata-attribute-role-syntax"><b>Syntax Representation – ttm:role</b></a>, and where the roles identified
+by this attribute express the semantic roles of the region
+independently from the semantic roles of any content targeted to
 (associated with) the region.</p></div></div><div class="div2">
-<h3><a name="layout-attribute-vocabulary" id="layout-attribute-vocabulary"/>9.2 Layout Attribute Vocabulary</h3><p>This section defines the <a href="#layout-attribute-region"><b>9.2.1 region</b></a> attribute used with content elements.</p><div class="div3">
-<h4><a name="layout-attribute-region" id="layout-attribute-region"/>9.2.1 region</h4><p>The <code>region</code> attribute is used to reference a <code>region</code>
-element which defines a space or area into which a content element is intended to be flowed.</p><p>The <code>region</code> attribute may be specified by an instance of the following
+<h3><a id="layout-attribute-vocabulary"></a>9.2 Layout Attribute Vocabulary</h3><p>This section defines the <a href="#layout-attribute-region"><b>9.2.1 region</b></a> attribute used with content elements.</p><div class="div3">
+<h4><a id="layout-attribute-region"></a>9.2.1 region</h4><p>The <code>region</code> attribute is used to reference a <code>region</code>
+element which defines a space or area into which a content element is intended to be flowed.</p><p>If specified, the value of a <code>region</code> attribute must
+adhere to the <code>IDREF</code> data type defined by <a href="#xsd-2">[XML Schema Part 2]</a>,
+§ 3.3.9, and, furthermore, this IDREF must reference a <code>region</code> element
+which has a <code>layout</code> element as an ancestor.</p><p>The <code>region</code> attribute may be specified by an instance of the following
 element types:</p><ul><li><p><a href="#document-structure-vocabulary-body"><code>body</code></a></p></li><li><p><a href="#content-vocabulary-div"><code>div</code></a></p></li><li><p><a href="#content-vocabulary-p"><code>p</code></a></p></li><li><p><a href="#content-vocabulary-span"><code>span</code></a></p></li></ul><div class="note"><p class="prefix"><b>Note:</b></p><p>See <a href="#semantics-region-layout"><b>9.3 Region Layout and Presentation</b></a> below for further information on content
 flow in a region.</p></div></div></div><div class="div2">
-<h3><a name="semantics-region-layout" id="semantics-region-layout"/>9.3 Region Layout and Presentation</h3><p>This section defines the semantics of region layout and
+<h3><a id="semantics-region-layout"></a>9.3 Region Layout and Presentation</h3><p>This section defines the semantics of region layout and
 presentation in terms of a standard processing model as
 follows:</p><ul><li><p><a href="#semantics-default-region"><b>9.3.1 Default Region</b></a></p></li><li><p><a href="#semantics-region-layout-step-1"><b>9.3.2 Intermediate Synchronic Document Construction</b></a></p></li><li><p><a href="#semantics-region-layout-step-2"><b>9.3.3 Synchronic Flow Processing</b></a></p></li><li><p><a href="#semantics-region-layout-example"><b>9.3.4 Elaborated Example (Informative)</b></a></p></li></ul><p>Any
 implementation is permitted provided that the externally observable
 results are consistent with the results produced by this model.
 </p><div class="div3">
-<h4><a name="semantics-default-region" id="semantics-default-region"/>9.3.1 Default Region</h4><p>If a TTML document instance does not specify a
+<h4><a id="semantics-default-region"></a>9.3.1 Default Region</h4><p>If a <em>Document Instance</em> does not specify a
 <a href="#layout-vocabulary-region"><code>region</code></a> element,
-then a <em>default region</em> is implied with the following characteristics:</p><ul><li><p>the identity of the default region is considered to be anonymous;</p></li><li><p>the extent of the default region is the same as the root container
-region;</p></li><li><p>the temporal interval of the default region is the same as temporal
-interval of the document instance;</p></li></ul><p>Furthermore, if no <a href="#layout-vocabulary-region"><code>region</code></a> element was
+then a <em>default region</em> is implied with the following characteristics:</p><ul><li><p>the identity of the default region is considered to be anonymous;</p></li><li><p>the extent of the default region is the same as the extent of the <em>Root Container Region</em>;</p></li><li><p>the temporal interval of the default region is the same as the interval defined by the <em>Root Temporal Extent</em>;</p></li></ul><p>Furthermore, if no <a href="#layout-vocabulary-region"><code>region</code></a> element is
 specified, then the <a href="#layout-attribute-region"><code>region</code></a> attribute must
-not be specified on any content element in the document
-instance.</p><p>If a default region is implied for a given document instance, then
+not be specified on any content element in the <em>Document Instance</em>.</p><p>If a default region is implied for a given <em>Document Instance</em>, then
 the <a href="#document-structure-vocabulary-body"><code>body</code></a> element
-is implicitly targeted to (associated with) the default region.</p><p>When implying a default region, the document instance is to be
+is implicitly targeted to (associated with) the default region.</p><p>When implying a default region, the <em>Document Instance</em> is to be
 treated as if a <a href="#layout-vocabulary-region"><code>region</code></a> element and its
 parent <a href="#layout-vocabulary-layout"><code>layout</code></a>
 element were specified in a <a href="#document-structure-vocabulary-head"><code>head</code></a>
 element, and a matching <a href="#layout-attribute-region"><code>region</code></a> attribute were
 specified on the <a href="#document-structure-vocabulary-body"><code>body</code></a> element
-as shown in the following example:</p><table summary="HTML Table" id="semantics-default-region-example" class="example"><caption>Example – Implied Default Region</caption><tbody><tr><td>
+as shown in the following example:</p><a id="semantics-default-region-example"></a><table class="example"><caption>Example – Implied Default Region</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;tt xml:lang="" xmlns="http://www.w3.org/ns/ttml"&gt;
   &lt;head&gt;
@@ -3796,24 +3981,30 @@
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the above example, a default <code>region</code> element and <code>region</code>
 attribute are implied. In addition, a <code>layout</code> container element is implied for
 the implied <code>region</code> element.</p></div></div><div class="div3">
-<h4><a name="semantics-region-layout-step-1" id="semantics-region-layout-step-1"/>9.3.2 Intermediate Synchronic Document Construction</h4><p>For the purposes of performing presentation processing, the active time
-duration of a document instance is divided into a sequence of time coordinates where at
+<h4><a id="semantics-region-layout-step-1"></a>9.3.2 Intermediate Synchronic Document Construction</h4><p>For the purposes of performing presentation processing, the active time
+duration of a <em>Document Instance</em> is divided into a sequence of time coordinates where at
 each time coordinate, some element becomes temporally active or inactive,
-then, at each such time coordinate, a document
-instance is mapped from its original, source
-form, <em>DOC<sub>source</sub></em>, 
+then, at each such time coordinate, a <em>Document Instance</em> is mapped from its original, source
+form, <em>DOC<sub>source</sub></em> , 
 to an intermediate
 synchronic document form,
-<em>DOC<sub>inter</sub></em>, as follows:</p><ol class="enumar"><li><p>for each temporally active region <em>R</em>, replicate the
+<em>DOC<sub>inter</sub></em> , according to the
+<span class="strong">[construct intermediate document]</span> procedure:</p><dl><dt class="label">[construct intermediate document]</dt><dd><ol class="enumar"><li><p>for each temporally active region <em>R</em>, replicate the
 sub-tree
  of <em>DOC<sub>source</sub></em>
 headed by the <code>body</code> element;</p></li><li><p>evaluating this sub-tree in a postorder traversal, prune elements if they
 are not a content element, if they are temporally inactive, if they are empty,
-or if they aren't associated with region <em>R</em>;</p></li><li><p>if the pruned sub-tree is non-empty, then reparent it to the <em>R</em>
+or if they aren't associated with region <em>R</em> according to the
+<span class="strong">[associate region]</span> procedure;</p></li><li><p>if the pruned sub-tree is non-empty, then reparent it to the <em>R</em>
 element;</p></li><li><p>finally, after completing the above steps, prune the original <code>body</code>
 element from the intermediate document, then prune all <code>region</code>,
 <code>begin</code>, <code>end</code>, and <code>dur</code> attributes, which are no
-longer semantically relevant;</p></li></ol><p>A content element is associated with a region according
+longer semantically relevant;</p></li></ol><div class="note"><p class="prefix"><b>Note:</b></p><p>In this section, the term <em>prune</em>, when used in reference to
+an element, means that the element is to be removed from its parent's children,
+which, in turn, implies that the descendants of the pruned element will no longer
+be descendants of the element's parent. When <em>prune</em> is used in
+reference to an attribute, it means that attribute is to be removed from its
+associated (owning) element node.</p></div></dd><dt class="label">[associate region]</dt><dd><p>A content element is associated with a region according
 to the following ordered rules, where the first rule satisfied
 is used and remaining rules are skipped:</p><ol class="enumar"><li><p>if the element specifies a <a href="#layout-attribute-region"><code>region</code></a> attribute,
 then the element is associated with the region referenced by that
@@ -3824,48 +4015,28 @@
 then the element is associated with the region referenced by that
 attribute;</p></li><li><p>if a default region was implied (due to the absence of any
 <a href="#layout-vocabulary-region"><code>region</code></a> element),
-then the element is associated with the default region;</p></li><li><p>the element is not associated with any region.</p></li></ol><p>The pseudo-code shown in <a href="#content-hierarchy-region-mapping"><b>Example – Content Hierarchy Region Mapping</b></a>
-provides one possible algorithm that implements these processing steps.</p><table summary="HTML Table" id="content-hierarchy-region-mapping" class="example"><caption>Example – Content Hierarchy Region Mapping</caption><tbody><tr><td>
-<div class="exampleInner"><pre>
-PREPARE-CONTENT ( D ) := 
-  foreach R in SELECT ( D, "/tt/head/layout/region" )
-    if TEMPORALLY-ACTIVE? ( R )
-      APPEND-CHILDREN ( R, SELECT ( D, "/tt/body" ) )
-      foreach E in POSTORDER-TRAVERSE ( R )
-        if ! CONTENT-ELEMENT? ( E ) or ! TEMPORALLY-ACTIVE? ( E ) or EMPTY? ( E ) or REGION-OF ( E ) != R
-            then PRUNE ( E )
-  PRUNE ( SELECT ( D, "/tt/body" ) )
-  PRUNE ( SELECT ( D, "//*/@region" ) )
-  PRUNE ( SELECT ( D, "//*/@begin" ) )
-  PRUNE ( SELECT ( D, "//*/@end" ) )
-  PRUNE ( SELECT ( D, "//*/@dur" ) )
- 
-REGION-OF ( E ) :=
-  if NULL? ( E )
-    return NULL
-  else if HAS-ATTRIBUTE? ( E, "region" )
-    return VALUE-OF-ATTRIBUTE ( E, "region" )
-  else
-    return REGION-OF ( PARENT-OF ( E ) )
-</pre></div>
-</td></tr></tbody></table><p>The result of performing the processing described above will be a sequence of
+then the element is associated with the default region;</p></li><li><p>the element is not associated with any region.</p></li></ol></dd></dl><p>The result of performing the processing described above will be a sequence of
 <em>N</em> intermediate  synchronic
-document instances,
+<em>Document Instances</em>,
 <em>DOC<sub><span>inter<sub>0</sub></span></sub></em> …
-<em>DOC<sub><span>inter<sub>N−1</sub></span></sub></em>.</p></div><div class="div3">
-<h4><a name="semantics-region-layout-step-2" id="semantics-region-layout-step-2"/>9.3.3 Synchronic Flow Processing</h4><p>Subsequent to performing a temporal (synchronic) slice and subsequent
+<em>DOC<sub><span>inter<sub>N−1</sub></span></sub></em>.</p><div class="note" id="semantics-smooth-scrolling-recommendation"><p class="prefix"><b>Note:</b></p><p>Where an implementation is able to detect significant similarity between two
+adjacent synchronic <em>Document Instances</em>,
+<em>DOC<sub><span>inter<sub>N</sub></span></sub></em>
+<em>DOC<sub><span>inter<sub>N−1</sub></span></sub></em>,
+then it is preferred that the implementation make the transition between
+presenting the two instances as smooth as possible, e.g., as described
+by <a href="#cea608c">[CEA-608-C]</a>, § C.3.</p></div></div><div class="div3">
+<h4><a id="semantics-region-layout-step-2"></a>9.3.3 Synchronic Flow Processing</h4><p>Subsequent to performing a temporal (synchronic) slice and subsequent
 remapping of regionally selected content hierarchy, the resulting intermediate
 synchronic document is subjected to a flow transformation step that produces 
-a rooted flow object tree represented as 
-an XSL FO document instance as defined by <a href="#xsl11">[XSL 1.1]</a>,
+a rooted flow object tree represented as an XSL FO document instance as defined by <a href="#xsl11">[XSL 1.1]</a>,
 and semantically extended by TTML specific style properties that have no XSL
 FO counterpart.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>In this section, the use of XSL FO is intended to be conceptual only, employed
 solely for the purpose of defining the normative presentation semantics of
 TTML. An actual implementation of this algorithm is not required to create or process
-XSL FO representations. In particular, it is possible to implement these semantics
-using alternative presentation models, such as Cascading Style Sheets (CSS).</p></div><p>Each intermediate synchronic  document produced by <a href="#semantics-region-layout-step-1"><b>9.3.2 Intermediate Synchronic Document Construction</b></a> is mapped 
-
-to a styled document <em>F</em> consistent with an XSL FO document instance, as follows</p><ol class="enumar"><li><p>perform the following ordered sub-steps to create anonymous spans:</p><ol class="enumla"><li><p>for each significant text node in a content element,
+XSL-FO representations. In particular, it is possible to implement these semantics
+using alternative presentation models, such as Cascading Style Sheets (CSS).</p></div><p>Each intermediate synchronic document produced by <a href="#semantics-region-layout-step-1"><b>9.3.2 Intermediate Synchronic Document Construction</b></a> is mapped 
+to an XSL FO document instance, <em>F</em>, as follows:</p><ol class="enumar"><li><p>perform the following ordered sub-steps to create anonymous spans:</p><ol class="enumla"><li><p>for each significant text node in a content element,
 synthesize an anonymous span to enclose the text node, substituting
 the new anonymous span for the original text node child in its sibling
 and parent hierarchy;</p></li><li><p>for each contiguous sequence of anonymous spans, replace the
@@ -3876,36 +4047,47 @@
 nodes;</p></li></ol></li><li><p>resolve styles according to <a href="#semantics-style-resolution-process-overall"><b>8.4.4.4 Style Resolution Process</b></a>;</p></li><li><p>map the <code>tt</code> element to an <code>fo:root</code> element, populated
 initially with an <code>fo:layout-master-set</code> element that contains a valid
 <code>fo:simple-page-master</code> that, in turn, contains an
-<code>fo:region-body</code> child, where the root container extent expressed on the
+<code>fo:region-body</code> child, where the extent of the <em>Root Container Region</em> expressed on the
 <code>tt</code> element is mapped to <code>page-width</code> and
 <code>page-height</code> attributes on the <code>fo:simple-page-master</code>
 element;</p></li><li><p>map the <code>layout</code> element to an <code>fo:page-sequence</code> element and a
 child <code>fo:flow</code> element that reference the page master and page region
 defined by the simple page master produced above;</p></li><li><p>map each non-empty <code>region</code> element to an <code>fo:block-container</code>
 element with an <code>absolute-position</code> attribute with value
-<code>absolute</code>, and where the region's position and extent are mapped to equivalent
-<code>top</code>, <code>left</code>, <code>width</code>, and <code>height</code>
-attributes;</p></li><li><p>for each <code>body</code>, <code>div</code>, and <code>p</code> element that is not
+<code>absolute</code>, with <code>top</code>, <code>left</code>, <code>bottom</code>, and <code>right</code>
+attributes that express a rectangle equivalent to the region's origin and
+extent, and with a <code>line-stacking-strategy</code> attribute with value <code>line-height</code>;</p></li><li><p>for each <code>body</code>, <code>div</code>, and <code>p</code> element that is not
 associated with a <code>tts:display</code> style property with the value
 <code>none</code>, map the element to a distinct <code>fo:block</code> element,
 populating the style properties of <code>fo:block</code> by using the computed
-style set associated with each original TTML content element;</p></li><li><p>for the resulting <code>fo:block</code> formatting object
+style set associated with each original TTML Content element;</p></li><li><p>for the resulting <code>fo:block</code> formatting object
 produced in the previous step that corresponds to the <code>body</code>
-element, synthesize and append to the end of its children an empty
-  <code>fo:block</code> with the following attributes:
+element, perform the following ordered sub-steps:</p><ol class="enumla"><li><p>if the <code>display-align</code> style property of this <code>fo:block</code>
+has the value <code>center</code> or <code>after</code>,
+then synthesize and insert as the first child of this <code>fo:block</code>
+an empty <code>fo:block</code> with the following attributes:
 <code>space-after.optimum</code>, <code>space-after.maximum</code>, and
 <code>space-after.conditionality</code>, where the value of the former
 two attributes is the height or width of the containing
 <code>fo:block-container</code> element, whichever of these is designated
 as the block progression dimension, and where the value of the last is
-<code>retain</code>;</p></li><li><p>for each <code>span</code> element that is not
+<code>retain</code>;</p></li><li><p>if the <code>display-align</code> style property of this <code>fo:block</code>
+has the value <code>center</code> or <code>before</code>,
+then synthesize and insert as the last child of this <code>fo:block</code>
+an empty <code>fo:block</code> with the following attributes:
+<code>space-after.optimum</code>, <code>space-after.maximum</code>, and
+<code>space-after.conditionality</code>, where the value of the former
+two attributes is the height or width of the containing
+<code>fo:block-container</code> element, whichever of these is designated
+as the block progression dimension, and where the value of the last is
+<code>retain</code>;</p></li></ol></li><li><p>for each <code>span</code> element that is not
 associated with a <code>tts:display</code> style property with the value
 <code>none</code> and for each anonymous
 span that is a child of a <code>p</code> or <code>span</code> element,
 map the element or
 sequence of character items to a distinct <code>fo:inline</code> element,
 populating the style properties of <code>fo:inline</code> by using the computed
-style set associated with each original TTML content element
+style set associated with each original TTML Content element
 or anonymous span;</p></li><li><p>for each <code>br</code> element that is not
 associated with a <code>tts:display</code> style property with the value
 <code>none</code>, map the element to
@@ -3913,26 +4095,32 @@
 properties:</p><ul><li><p><code>character="&amp;#x000A;"</code></p></li><li><p><code>suppress-at-line-break="retain"</code></p></li></ul></li><li><p>for each TTML style property attribute in some computed
 style set that
 has no counterpart in <a href="#xsl11">[XSL 1.1]</a>, map that attribute directly through
-to the relevant formatting object produced by the input TTML content element to
+to the relevant formatting object produced by the input TTML Content element to
 which the style property applies;</p></li><li><p>optionally, synthesize a unique <code>id</code> attribute on each resulting
 formatting object element that relates that element to the input element that
 resulted in that formatting object element;</p></li></ol><p>For each resulting document instance F, if processing requires presentation on a 
-  visual medium, then apply formatting and rendering semantics consistent with that 
-  prescribed by <a href="#xsl11">[XSL 1.1]</a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>In an XSL FO area tree produced by formatting <em>F</em> using 
+visual medium, then apply formatting and rendering semantics consistent with that 
+prescribed by <a href="#xsl11">[XSL 1.1]</a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>In an XSL FO area tree produced by formatting <em>F</em> using 
 an <a href="#xsl11">[XSL 1.1]</a> formatting processor, 
 the <code>page-viewport-area</code>,
 which is generated by <code>fo:page-sequence</code> element by
 reference to the sole generated <code>fo:simple-page-master</code>
-element, would correspond to the <em>root container region</em> defined
-above in <a href="#definitions"><b>2 Definitions</b></a>.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>
-  Due to the possible presence of TTML style properties or style property values
-  in a given TTML document instance for which there is no <a href="#xsl11">[XSL 1.1]</a> counterpart,
-  Implementors should recognize that it is the layout model of <a href="#xsl11">[XSL 1.1]</a> that is being referenced
-  by this specification, not the requirement to use a compliant <a href="#xsl11">[XSL 1.1]</a> formatting processor,
-  since such would not necessarily be sufficient to satisfy the full presentation semantics
-  defined by this specification, and would contain a large number of features not needed to
-  implement the presentation semantics of TTML.</p></div></div><div class="div3">
-<h4><a name="semantics-region-layout-example" id="semantics-region-layout-example"/>9.3.4 Elaborated Example (Informative)</h4><p>An example of the processing steps described above is elaborated below, starting with <a href="#region-mapping-example-1-s"><b>Example – Sample Source Document</b></a>.</p><table summary="HTML Table" id="region-mapping-example-1-s" class="example"><caption>Example – Sample Source Document</caption><tbody><tr><td>
+element, would correspond to the <em>Root Container Region</em> defined
+above in <a href="#definitions"><b>2 Definitions</b></a>.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>Due to the possible presence of TTML style properties or style property values
+in a given <em>Document Instance</em> for which there is no <a href="#xsl11">[XSL 1.1]</a> counterpart,
+Implementors should recognize that it is the layout model of <a href="#xsl11">[XSL 1.1]</a> that is being referenced
+by this specification, not the requirement to use a compliant <a href="#xsl11">[XSL 1.1]</a> formatting processor,
+since such would not necessarily be sufficient to satisfy the full presentation semantics
+defined by this specification, and would contain a large number of features not needed to
+implement the presentation semantics of TTML.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>The purpose of inserting additional, collapsible space in the block progression
+dimension of the <code>fo:block</code> that corresponds with the <code>body</code> element
+is to ensure that the before and after edges of this <code>fo:block</code> are coincident
+with the before and after edges of the <code>fo:block-container</code> that corresponds
+to the containing <code>region</code>, while simultaneously taking into account the needs
+to satisfy alignment in the block progression dimension. For example, this assures that
+the background color associated with the <code>body</code> element, if not <code>transparent</code>,
+ will fill the containing region wholly.</p></div></div><div class="div3">
+<h4><a id="semantics-region-layout-example"></a>9.3.4 Elaborated Example (Informative)</h4><p>An example of the processing steps described above is elaborated below, starting with <a href="#region-mapping-example-1-s"><b>Example – Sample Source Document</b></a>.</p><a id="region-mapping-example-1-s"></a><table class="example"><caption>Example – Sample Source Document</caption><tbody><tr><td>
 <div class="exampleInner"><pre>&lt;tt tts:extent="640px 480px" xml:lang="en"
   xmlns="http://www.w3.org/ns/ttml"
   xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
@@ -3973,15 +4161,15 @@
 &lt;/tt&gt;
 </pre></div>
 </td></tr></tbody></table><p>In the above document, the content hierarchy consists of two divisions, each
-containing two paragraphs. This content is targeted (selected into) one of two
+containing two paragraphs. This content is targeted (associated with) one of two
 non-overlapping regions that are styled identically except for their position
 and their foreground colors, the latter of which is inherited by and applies to
-the (and, in this case, anonymous) spans reparented into the regions.</p><p>The following, first intermediate document shows the synchronic state at time
+the (and, in this case, anonymous) spans reparented into the regions.</p><p>The following, first intermediate document shows the synchronic state for time
 interval [0,1), during which time only division <code>d1</code> is temporally active,
 and where paragraphs <code>p1</code> and <code>p2</code> (and their ancestors)
-are selected into regions <code>r1</code> and <code>r2</code>, respectively.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The intermediate documents shown below are not valid TTML document instances,
+are associated with regions <code>r1</code> and <code>r2</code>, respectively.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The intermediate documents shown below are not valid <em>Document Instances</em>,
 but rather, are representations of possible internal processing states used for
-didactic purposes.</p></div><table summary="HTML Table" id="region-mapping-example-1-i0" class="example"><caption>Example – Intermediate Document – [0s,1s)</caption><tbody><tr><td>
+didactic purposes.</p></div><a id="region-mapping-example-1-i0"></a><table class="example"><caption>Example – Intermediate Document – [0s,1s)</caption><tbody><tr><td>
 <div class="exampleInner"><pre>&lt;tt tts:extent="640px 480px" xml:lang="en"
   xmlns="http://www.w3.org/ns/ttml"
   xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
@@ -4021,12 +4209,9 @@
   &lt;/head&gt;
 &lt;/tt&gt;
 </pre></div>
-</td></tr></tbody></table><p>
-  
-  An XSL FO document instance that would yield rendering consistent with TTML, and 
-  which may be produced by performing flow processing upon the first intermediate 
-  document is illustrated below.
-</p><table summary="HTML Table" id="region-mapping-example-1-f0" class="example"><caption>Example – XSL FO Document – [0s,1s)</caption><tbody><tr><td>
+</td></tr></tbody></table><p>An XSL FO document instance that would yield rendering consistent with TTML, and 
+which may be produced by performing flow processing upon the first intermediate 
+document is illustrated below.</p><a id="region-mapping-example-1-f0"></a><table class="example"><caption>Example – XSL FO Document – [0s,1s)</caption><tbody><tr><td>
 <div class="exampleInner"><pre>&lt;fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format"&gt;
   &lt;fo:layout-master-set&gt;
     &lt;fo:simple-page-master master-name="m1"
@@ -4042,6 +4227,11 @@
         background-color="black" display-align="center"&gt;
         &lt;!-- body (b1) --&gt;
         &lt;fo:block id="b1-1"&gt;
+          &lt;!-- body's space (before) filler --&gt;
+          &lt;fo:block
+            space-after.optimum="96px"
+            space-after.maximum="96px"
+            space-after.conditionality="retain"/&gt;
           &lt;!-- div (d1) --&gt;
           &lt;fo:block id="d1-1"&gt;
             &lt;!-- p (p1) --&gt;
@@ -4050,7 +4240,7 @@
               color="red"&gt;Text 1&lt;/fo:inline&gt;
             &lt;/fo:block&gt;
           &lt;/fo:block&gt;
-          &lt;!-- body's space filler -&gt;
+          &lt;!-- body's space (after) filler --&gt;
           &lt;fo:block
             space-after.optimum="96px"
             space-after.maximum="96px"
@@ -4063,6 +4253,11 @@
         background-color="black" display-align="center"&gt;
         &lt;!-- body (b1) --&gt;
         &lt;fo:block id="b1-2"&gt;
+          &lt;!-- body's space (before) filler --&gt;
+          &lt;fo:block
+            space-after.optimum="96px"
+            space-after.maximum="96px"
+            space-after.conditionality="retain"/&gt;
           &lt;!-- div (d1) --&gt;
           &lt;fo:block id="d1-2"&gt;
             &lt;!-- p (p2) --&gt;
@@ -4071,7 +4266,7 @@
               color="yellow"&gt;Text 2&lt;/fo:inline&gt;
             &lt;/fo:block&gt;
           &lt;/fo:block&gt;
-          &lt;!-- body's space filler -&gt;
+          &lt;!-- body's space (after) filler --&gt;
           &lt;fo:block
             space-after.optimum="96px"
             space-after.maximum="96px"
@@ -4082,12 +4277,12 @@
   &lt;/fo:page-sequence&gt;
 &lt;/fo:root&gt;
 </pre></div>
-</td></tr></tbody></table><p>The following, second intermediate document shows the synchronic state at
-time interval [1,2), at which time both divisions <code>d1</code> and
+</td></tr></tbody></table><p>The following, second intermediate document shows the synchronic state for
+time interval [1,2), during which time both divisions <code>d1</code> and
 <code>d2</code> are temporally active, and where paragraphs <code>p1</code> and
-<code>p4</code> (and their ancestors) are selected into region <code>r1</code>
+<code>p4</code> (and their ancestors) are associated with region <code>r1</code>
 and paragraphs <code>p2</code> and <code>p3</code> (and their ancestors) are
-selected into region <code>r2</code>.</p><table summary="HTML Table" id="region-mapping-example-1-i1" class="example"><caption>Example – Intermediate Document – [1s,2s)</caption><tbody><tr><td>
+associated with region <code>r2</code>.</p><a id="region-mapping-example-1-i1"></a><table class="example"><caption>Example – Intermediate Document – [1s,2s)</caption><tbody><tr><td>
 <div class="exampleInner"><pre>&lt;tt tts:extent="640px 480px" xml:lang="en"
   xmlns="http://www.w3.org/ns/ttml"
   xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
@@ -4133,10 +4328,10 @@
   &lt;/head&gt;
 &lt;/tt&gt;
 </pre></div>
-</td></tr></tbody></table><p>The following, third intermediate document shows the synchronic state at time
-interval [2,3), at which time only division <code>d2</code> is temporally active,
+</td></tr></tbody></table><p>The following, third intermediate document shows the synchronic state for time
+interval [2,3), during which time only division <code>d2</code> is temporally active,
 and where paragraphs <code>p4</code> and <code>p3</code> (and their ancestors)
-are selected into regions <code>r1</code> and <code>r2</code>, respectively.</p><table summary="HTML Table" id="region-mapping-example-1-i2" class="example"><caption>Example – Intermediate Document – [2s,3s)</caption><tbody><tr><td>
+are associated with regions <code>r1</code> and <code>r2</code>, respectively.</p><a id="region-mapping-example-1-i2"></a><table class="example"><caption>Example – Intermediate Document – [2s,3s)</caption><tbody><tr><td>
 <div class="exampleInner"><pre>&lt;tt tts:extent="640px 480px" xml:lang="en"
   xmlns="http://www.w3.org/ns/ttml"
   xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
@@ -4177,29 +4372,29 @@
 &lt;/tt&gt;
 </pre></div>
 </td></tr></tbody></table></div></div><div class="div2">
-<h3><a name="semantics-line-layout" id="semantics-line-layout"/>9.4 Line Layout</h3><p>If a profile that applies to a document instance
+<h3><a id="semantics-line-layout"></a>9.4 Line Layout</h3><p>If a profile that applies to a <em>Document Instance</em>
 requires use of the <a href="#feature-lineBreak-uax14">#lineBreak-uax14</a> feature
 (i.e., the value attribute for the feature is specified as <code>use</code>), then
-the recommendations defined by <a href="http://www.unicode.org/unicode/reports/tr14/#Algorithm">Line
+the recommendations defined by <a href="http://www.unicode.org/reports/tr14/#Algorithm">Line
 Breaking Algorithm</a> <a href="#uax14">[UAX14]</a> apply when performing
-line layout on the content of the document instance.</p></div></div><div class="div1">
-<h2><a name="timing" id="timing"/>10 Timing</h2><p>This section specifies the <em>timing</em> matter of the core
+line layout on the content of the <em>Document Instance</em>.</p></div></div><div class="div1">
+<h2><a id="timing"></a>10 Timing</h2><p>This section specifies the <em>timing</em> matter of the core
 vocabulary catalog, where
 timing is to be understood as a separable layer of information that applies to
 content and that denotes authorial intentions about the temporal presentation of
 that content.</p><div class="div2">
-<h3><a name="timing-element-vocabulary" id="timing-element-vocabulary"/>10.1 Timing Element Vocabulary</h3><p>No timing related element vocabulary is defined for use in the core
+<h3><a id="timing-element-vocabulary"></a>10.1 Timing Element Vocabulary</h3><p>No timing related element vocabulary is defined for use in the core
 vocabulary catalog.</p></div><div class="div2">
-<h3><a name="timing-attribute-vocabulary" id="timing-attribute-vocabulary"/>10.2 Timing Attribute Vocabulary</h3><p>This section defines the following basic timing attributes for use with timed elements:</p><ul><li><p><a href="#timing-attribute-begin"><b>10.2.1 begin</b></a></p></li><li><p><a href="#timing-attribute-end"><b>10.2.2 end</b></a></p></li><li><p><a href="#timing-attribute-dur"><b>10.2.3 dur</b></a></p></li></ul><p>In addition, this section defines the <a href="#timing-attribute-timeContainer"><b>10.2.4 timeContainer</b></a> attribute for use with timed elements
+<h3><a id="timing-attribute-vocabulary"></a>10.2 Timing Attribute Vocabulary</h3><p>This section defines the following basic timing attributes for use with timed elements:</p><ul><li><p><a href="#timing-attribute-begin"><b>10.2.1 begin</b></a></p></li><li><p><a href="#timing-attribute-end"><b>10.2.2 end</b></a></p></li><li><p><a href="#timing-attribute-dur"><b>10.2.3 dur</b></a></p></li></ul><p>In addition, this section defines the <a href="#timing-attribute-timeContainer"><b>10.2.4 timeContainer</b></a> attribute for use with timed elements
 that serve simultaneously as timing containers.</p><div class="div3">
-<h4><a name="timing-attribute-begin" id="timing-attribute-begin"/>10.2.1 begin</h4><p>The <code>begin</code> attribute is used to specify the begin
+<h4><a id="timing-attribute-begin"></a>10.2.1 begin</h4><p>The <code>begin</code> attribute is used to specify the begin
 point of a temporal interval associated with a timed element. If
 specified, the value of a <code>begin</code> attribute must adhere to
 a &lt;timeExpression&gt; specification as defined by <a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a>.</p><p>The begin point of a temporal interval is included in the
 interval; i.e., the interval is left-wise closed.</p><p>The semantics of the <code>begin</code> attribute are those defined
 by <a href="#smil21">[SMIL 2.1]</a>, § 10.4.1,
 while taking into account any overriding semantics defined by this specification.</p></div><div class="div3">
-<h4><a name="timing-attribute-end" id="timing-attribute-end"/>10.2.2 end</h4><p>The <code>end</code> attribute is used to specify the ending point
+<h4><a id="timing-attribute-end"></a>10.2.2 end</h4><p>The <code>end</code> attribute is used to specify the ending point
 of a temporal interval associated with a timed element. If
 specified, the value of an <code>end</code> attribute must adhere to a
 &lt;timeExpression&gt; specification as defined by <a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a>.</p><p>The ending point of a temporal interval is not included in the
@@ -4213,14 +4408,14 @@
 as [300f,310f).</p></div><p>The semantics of the <code>end</code> attribute are those defined
 by <a href="#smil21">[SMIL 2.1]</a>, § 10.4.1,
 while taking into account any overriding semantics defined by this specification.</p></div><div class="div3">
-<h4><a name="timing-attribute-dur" id="timing-attribute-dur"/>10.2.3 dur</h4><p>The <code>dur</code> attribute is used to specify the duration of a
+<h4><a id="timing-attribute-dur"></a>10.2.3 dur</h4><p>The <code>dur</code> attribute is used to specify the duration of a
 temporal interval associated with a timed element. If specified,
 the value of a <code>dur</code> attribute must adhere to a
 &lt;timeExpression&gt; specification as defined by <a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>When the <code>clock-time</code> form of a &lt;timeExpression&gt; specification
 is used with a <code>dur</code> attribute, it is intended to be interpreted as
-a difference between two implied clock time expressions.</p></div><p>When a TTML document instance specifies the use of the
+a difference between two implied clock time expressions.</p></div><p>When a <em>Document Instance</em> specifies the use of the
 <code>smpte</code> time base and <code>discontinuous</code> marker
-mode, the <code>dur</code> attribute must not be specified on any
+mode, a (well-formed) <code>dur</code> attribute must not be specified on any
 element.</p><p>The semantics of the <code>dur</code> attribute are those defined
 by <a href="#smil21">[SMIL 2.1]</a>, § 10.4.1,
 while taking into account any overriding semantics defined by this specification.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>In the context of the subset of <a href="#smil21">[SMIL 2.1]</a> semantics supported by
@@ -4228,13 +4423,17 @@
 <code>end</code> and <code>dur</code> attributes is equal to the lesser of the value of
 the <code>dur</code> attribute and the difference between the value of the
 <code>end</code> attribute and the element's begin time.</p></div></div><div class="div3">
-<h4><a name="timing-attribute-timeContainer" id="timing-attribute-timeContainer"/>10.2.4 timeContainer</h4><p>The <code>timeContainer</code> attribute is used to specify a local temporal
+<h4><a id="timing-attribute-timeContainer"></a>10.2.4 timeContainer</h4><p>The <code>timeContainer</code> attribute is used to specify a local temporal
 context by means of which timed child elements are temporally situated.</p><p>If specified, the value of a <code>timeContainer</code> attribute must be one
 of the following:</p><ul><li><p><code>par</code></p></li><li><p><code>seq</code></p></li></ul><p>If the time container semantics of an element instance is <code>par</code>,
 then the temporal intervals of child elements are considered to apply in
 parallel, i.e., simultaneously in time. Furthermore, the specification of
 the time interval of each child element is considered to be relative to the temporal
-interval of the container element instance.</p><p>If the time container semantics of an element instance is <code>seq</code>,
+interval of the container element instance. For the purpose of determining the
+<a href="#smil21">[SMIL 2.1]</a> <code>endsync</code> semantics of a <code>par</code>
+time container, a default value of <code>all</code> applies.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The use of a default value of <code>all</code> for the <code>endsync</code>
+behavior is distinct from <a href="#smil21">[SMIL 2.1]</a> which uses a default value
+of <code>last</code>.</p></div><p>If the time container semantics of an element instance is <code>seq</code>,
 then the temporal intervals of child elements are considered to apply in
 sequence, i.e., sequentially in time. Furthermore, the specification of
 the time interval of each child element is considered to be relative to the temporal
@@ -4245,12 +4444,16 @@
 has time container semantics, then <code>par</code> time container semantics must apply.</p><p>Time container semantics applies only to the following element types:</p><ul><li><p><a href="#document-structure-vocabulary-body"><code>body</code></a></p></li><li><p><a href="#content-vocabulary-div"><code>div</code></a></p></li><li><p><a href="#content-vocabulary-p"><code>p</code></a></p></li><li><p><a href="#layout-vocabulary-region"><code>region</code></a></p></li><li><p><a href="#content-vocabulary-span"><code>span</code></a></p></li></ul><p>The semantics of parallel and sequential time
 containment are those defined by <a href="#smil21">[SMIL 2.1]</a>, § 10.4.2,
 while taking into account any overriding semantics defined by this specification.</p></div></div><div class="div2">
-<h3><a name="timing-time-value-expressions" id="timing-time-value-expressions"/>10.3 Time Value Expressions</h3><p>Timing attribute values include the use of the following expressions:</p><ul><li><p><a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a></p></li></ul><div class="div3">
-<h4><a name="timing-value-timeExpression" id="timing-value-timeExpression"/>10.3.1 &lt;timeExpression&gt;</h4><p>A &lt;timeExpression&gt; is used to specify a coordinate along
+<h3><a id="timing-time-value-expressions"></a>10.3 Time Value Expressions</h3><p>Timing attribute values include the use of the following expressions:</p><ul><li><p><a href="#timing-value-timeExpression"><b>10.3.1 &lt;timeExpression&gt;</b></a></p></li></ul><div class="div3">
+<h4><a id="timing-value-timeExpression"></a>10.3.1 &lt;timeExpression&gt;</h4><p>A &lt;timeExpression&gt; is used to specify a coordinate within
 some time base, where the applicable time base is determined by the
-<code>ttp:timeBase</code> parameter.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>See <a href="#parameter-attribute-timeBase"><b>6.2.11 ttp:timeBase</b></a>, <a href="#parameter-attribute-frameRate"><b>6.2.4 ttp:frameRate</b></a>, <a href="#parameter-attribute-subFrameRate"><b>6.2.9 ttp:subFrameRate</b></a>, and <a href="#parameter-attribute-tickRate"><b>6.2.10 ttp:tickRate</b></a> for further information on
-explicit specification of time base, frame rate, sub-frame rate, and
-tick rate.</p></div><table summary="HTML Table" id="timeExpression-syntax" class="syntax"><caption>Syntax Representation – &lt;timeExpression&gt;</caption><tbody><tr><td>
+<code>ttp:timeBase</code> parameter, and where the semantics defined
+by <a href="#time-expression-semantics"><b>N Time Expression Semantics</b></a> apply.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>See
+<a href="#parameter-attribute-frameRate"><b>6.2.4 ttp:frameRate</b></a>,
+<a href="#parameter-attribute-subFrameRate"><b>6.2.9 ttp:subFrameRate</b></a>,
+<a href="#parameter-attribute-tickRate"><b>6.2.10 ttp:tickRate</b></a>, and
+<a href="#parameter-attribute-timeBase"><b>6.2.11 ttp:timeBase</b></a> for further information on
+explicit specification of frame rate, sub-frame rate, tick rate, and time base.</p></div><a id="timeExpression-syntax"></a><table class="syntax"><caption>Syntax Representation – &lt;timeExpression&gt;</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;timeExpression&gt;
   : clock-time
@@ -4292,68 +4495,59 @@
 </pre></div>
 </td></tr></tbody></table><p>If a &lt;timeExpression&gt; is expressed in terms of a
 <em>clock-time</em>, then leading zeroes are used when expressing hours,
-minutes, seconds, and frames less than 10. Minutes are constrained to the range
-[0…59], while seconds are constrained to [0…60], where the value 60
-applies only to leap seconds.</p><p>If a &lt;timeExpression&gt; is expressed in terms of a
+minutes, seconds, and frames less than 10. Minutes are constrained to
+[0…59], while seconds (including any fractional part) are constrained to the closed
+interval [0,60], where the value 60 applies only to leap seconds.</p><p>If a &lt;timeExpression&gt; is expressed in terms of a
 <em>clock-time</em> and a <em>frames</em> term is specified,
 then the value of this term must be constrained to the interval
 [0…<em>F-1</em>], where <em>F</em> is the frame rate
 determined by the <code>ttp:frameRate</code> parameter as defined
-by <a href="#parameter-attribute-frameRate"><b>6.2.4 ttp:frameRate</b></a>.</p><p>If a &lt;timeExpression&gt; is expressed in terms of a
+by <a href="#parameter-attribute-frameRate"><b>6.2.4 ttp:frameRate</b></a>.
+It is considered an error if a <em>frames</em> term or
+<code>f</code> (frames) metric is specified when the <code>clock</code> time base applies.</p><p>If a &lt;timeExpression&gt; is expressed in terms of a
 <em>clock-time</em> and a <em>sub-frames</em> term is
 specified, then the value of this term must be constrained to the
 interval [0…<em>S-1</em>], where <em>S</em> is the
-sub-frame rate determined by the <code>ttp:subFrameRate</code> parameter as defined by <a href="#parameter-attribute-subFrameRate"><b>6.2.9 ttp:subFrameRate</b></a>.</p></div></div><div class="div2">
-<h3><a name="timing-time-intervals" id="timing-time-intervals"/>10.4 Time Intervals</h3><p>The semantics of time containment, durations, and intervals defined by
+sub-frame rate determined by the <code>ttp:subFrameRate</code> parameter as defined by <a href="#parameter-attribute-subFrameRate"><b>6.2.9 ttp:subFrameRate</b></a>.
+It is considered an error if a <em>sub-frames</em> term is specified
+when the <code>clock</code> time base applies.</p></div></div><div class="div2">
+<h3><a id="timing-time-intervals"></a>10.4 Time Intervals</h3><p>The semantics of time containment, durations, and intervals defined by
 <a href="#smil21">[SMIL 2.1]</a> apply to the interpretation of like-named timed elements and timing
 vocabulary defined by this specification, given the following
-constraints:</p><ul><li><p>The implicit duration of
-
-an anonymous span
-
-is defined as follows: if
-the
-
-anonymous span's
-
-parent time container is a parallel time container, then
+constraints:</p><ul><li><p>The implicit duration of an anonymous span is defined as follows: if
+the anonymous span's parent time container is a parallel time container, then
 the implicit duration is equivalent to the <code>indefinite</code>
-duration value as defined by <a href="#smil21">[SMIL 2.1]</a>; if the
-
-anonymous span's
-
-parent time container is a sequential time container, then the
-implicit duration is equivalent to zero.</p></li><li><p>The implicit duration of a <code>body</code>, <code>div</code>, <code>p</code>,
+duration value as defined by <a href="#smil21">[SMIL 2.1]</a>; if the anonymous span's
+parent time container is a sequential time container, then the implicit duration
+is equivalent to zero.</p></li><li><p>The implicit duration of a <code>body</code>, <code>div</code>, <code>p</code>,
 or <code>span</code> element is determined in accordance to (1) whether
-the element is a parallel or sequential time container, and (2) the
-semantics of <a href="#smil21">[SMIL 2.1]</a> as applied to these time
+the element is a parallel or sequential time container, (2) the default
+<code>endsync</code> semantics defined above by <a href="#timing-attribute-timeContainer"><b>10.2.4 timeContainer</b></a>,
+and (3) the semantics of <a href="#smil21">[SMIL 2.1]</a> as applied to these time
 containers.</p></li><li><p>The implicit duration of the <code>region</code> element is defined to
 be equivalent to the <code>indefinite</code>
-duration value as defined by <a href="#smil21">[SMIL 2.1]</a>.</p></li><li><p>If the governing time mode is <code>media</code> or
-<code>smpte</code> with mode <code>continuous</code>, then time
-expressions must be interpreted as
-equivalent to offset based timing
-in <a href="#smil21">[SMIL 2.1]</a>, namely, as offsets from an implicit
-syncbase.</p></li><li><p>If the governing time mode is <code>smpte</code> with mode
-<code>discontinuous</code>, then time expressions must be interpreted
-as equivalent to marker values produced by an external marker event
-source, in which case all time expressions are equivalent to event
-based timing in <a href="#smil21">[SMIL 2.1]</a>.</p></li><li><p>If the governing time mode is <code>clock</code>, then time
-expressions must be interpreted as equivalent to wallclock time
-expressions in <a href="#smil21">[SMIL 2.1]</a>, where the applicable wallclock
-used is determined by the clock mode parameter.</p></li></ul></div></div><div class="div1">
-<h2><a name="animation" id="animation"/>11 Animation</h2><p>This section specifies the <em>animation</em> matter of the
+duration value as defined by <a href="#smil21">[SMIL 2.1]</a>.</p></li><li><p>If the governing time base is <code>clock</code>, then time
+expressions are considered to be equivalent to wall-clock
+based timing in <a href="#smil21">[SMIL 2.1]</a>, where the specific semantics of
+<a href="#time-expression-semantics-clock"><b>N.1 Clock Time Base</b></a> apply.</p></li><li><p>If the governing time base is <code>media</code>, then time
+expressions are considered to be equivalent to offset based timing
+in <a href="#smil21">[SMIL 2.1]</a>, where the specific semantics of
+<a href="#time-expression-semantics-media"><b>N.2 Media Time Base</b></a> apply.</p></li><li><p>If the governing time base is <code>smpte</code>, then time
+expressions are considered to be equivalent to either offset
+based timing or event based timing in <a href="#smil21">[SMIL 2.1]</a>, where the specific semantics of
+<a href="#time-expression-semantics-smpte"><b>N.3 SMPTE Time Base</b></a> apply.</p></li></ul></div></div><div class="div1">
+<h2><a id="animation"></a>11 Animation</h2><p>This section specifies the <em>animation</em> matter of the
 core vocabulary catalog, where
 animation is to be understood as a separable layer of information that combines
 timing and styling in order to denote authorial intention about (temporally) dynamic
 styling of content.</p><div class="div2">
-<h3><a name="animation-element-vocabulary" id="animation-element-vocabulary"/>11.1 Animation Element Vocabulary</h3><p>The following elements specify the structure and principal animation aspects of a
-document instance:</p><ul><li><p><a href="#animation-vocabulary-set"><b>11.1.1 set</b></a></p></li></ul><div class="div3">
-<h4><a name="animation-vocabulary-set" id="animation-vocabulary-set"/>11.1.1 set</h4><p>The <code>set</code> element is used as a child element of a content
+<h3><a id="animation-element-vocabulary"></a>11.1 Animation Element Vocabulary</h3><p>The following elements specify the structure and principal animation aspects of a
+<em>Document Instance</em>:</p><ul><li><p><a href="#animation-vocabulary-set"><b>11.1.1 set</b></a></p></li></ul><div class="div3">
+<h4><a id="animation-vocabulary-set"></a>11.1.1 set</h4><p>The <code>set</code> element is used as a child element of a content
 element or a <code>region</code> element
 in order to express a discrete change of some style parameter value
 that applies over some time interval.</p><p>The <code>set</code> element accepts as its children zero or more
-elements in the <code>Metadata.class</code> element group.</p><table summary="HTML Table" id="elt-syntax-set" class="syntax"><caption>XML Representation – Element Information Item: set</caption><tbody><tr><td>
+elements in the <code>Metadata.class</code> element group.</p><a id="elt-syntax-set"></a><table class="syntax"><caption>XML Representation – Element Information Item: set</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;set
   <a href="#timing-attribute-begin">begin</a> = <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>
@@ -4369,7 +4563,7 @@
 </pre></div>
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The use of multiple <code>set</code> element children may be used to effect fade and
 position transitions.</p></div><p>An example of using the <code>set</code> element to animate content
-styling is illustrated below:</p><table summary="HTML Table" id="animation-vocabulary-set-example-1" class="example"><caption>Example Fragment – Content Style Animation</caption><tbody><tr><td>
+styling is illustrated below:</p><a id="animation-vocabulary-set-example-1"></a><table class="example"><caption>Example Fragment – Content Style Animation</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ...
 &lt;p dur="5s" tts:color="yellow"&gt;
@@ -4383,7 +4577,7 @@
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the above example, the foreground color of the content "Text
 with Flashing Colors" is animated from yellow, to red, to green, to
 red, then back to yellow over a 5 second period.</p></div><p>An example of using the <code>set</code> element to animate region
-styling is illustrated below:</p><table summary="HTML Table" id="animation-vocabulary-set-example-2" class="example"><caption>Example Fragment – Region Style Animation</caption><tbody><tr><td>
+styling is illustrated below:</p><a id="animation-vocabulary-set-example-2"></a><table class="example"><caption>Example Fragment – Region Style Animation</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;tt xml:lang="" xmlns="http://www.w3.org/ns/ttml"
     xmlns:ttp="http://www.w3.org/ns/ttml#parameter"
@@ -4404,39 +4598,37 @@
     &lt;body region="r1"&gt;...&lt;/body&gt;
 &lt;/tt&gt;
 </pre></div>
-</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the above example, the root container region is divided into a
+</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the above example, the <em>Root Container Region</em> is divided into a
 cell grid of 40 columns and 16 rows. A region, <code>r1</code>, with
 dimensions of 24 columns and 2 rows is then positioned within the
-root container region, with its position varying over time in order to
+<em>Root Container Region</em>, with its position varying over time in order to
 create an effect of moving the region, which may be desirable so as
 to avoid obscuring characters in an underlying video with captions.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>The semantics of the <code>set</code> element
 are based upon that defined by <a href="#smil21">[SMIL 2.1]</a>,
 § 3.6.2.</p></div></div></div><div class="div2">
-<h3><a name="animation-attribute-vocabulary" id="animation-attribute-vocabulary"/>11.2 Animation Attribute Vocabulary</h3><p>No animation related attribute vocabulary is defined for use in the
+<h3><a id="animation-attribute-vocabulary"></a>11.2 Animation Attribute Vocabulary</h3><p>No animation related attribute vocabulary is defined for use in the
 core vocabulary catalog.</p></div></div><div class="div1">
-<h2><a name="metadata" id="metadata"/>12 Metadata</h2><p>This section specifies the <em>metadata</em> matter of the core
+<h2><a id="metadata"></a>12 Metadata</h2><p>This section specifies the <em>metadata</em> matter of the core
 vocabulary catalog, where
 metadata is to be understood as a separable layer of information that applies to
 parameters, content,
 style, layout, timing, and even metadata itself, where the information
 represented by metadata takes one of two forms: (1) metadata defined by this
-specification for standardized use in a document instance, and (2) arbitrary
+specification for standardized use in a <em>Document Instance</em>, and (2) arbitrary
 metadata defined outside of the scope of this specification, whose use and
-semantics depend entirely upon an application's use of TTML content.</p><div class="div2">
-<h3><a name="metadata-element-vocabulary" id="metadata-element-vocabulary"/>12.1 Metadata Element Vocabulary</h3><p>The <a href="#metadata-vocabulary-metadata"><b>12.1.1 metadata</b></a> element serves as
+semantics depend entirely upon an application's use of TTML Content.</p><div class="div2">
+<h3><a id="metadata-element-vocabulary"></a>12.1 Metadata Element Vocabulary</h3><p>The <a href="#metadata-vocabulary-metadata"><b>12.1.1 metadata</b></a> element serves as
 a generic container element for grouping metadata information.</p><p>In addition, the following elements, all defined in the TT Metadata Namespace,
-provide standard representations for common metadata that is expected to be commonly
-used in a document instances:
+provide standard representations for metadata that is expected to be commonly
+used in a <em>Document Instances</em>:
 </p><ul><li><p><a href="#metadata-vocabulary-title"><b>12.1.2 ttm:title</b></a></p></li><li><p><a href="#metadata-vocabulary-desc"><b>12.1.3 ttm:desc</b></a></p></li><li><p><a href="#metadata-vocabulary-copyright"><b>12.1.4 ttm:copyright</b></a></p></li><li><p><a href="#metadata-vocabulary-agent"><b>12.1.5 ttm:agent</b></a></p></li><li><p><a href="#metadata-vocabulary-name"><b>12.1.6 ttm:name</b></a></p></li><li><p><a href="#metadata-vocabulary-actor"><b>12.1.7 ttm:actor</b></a></p></li></ul><div class="div3">
-<h4><a name="metadata-vocabulary-metadata" id="metadata-vocabulary-metadata"/>12.1.1 metadata</h4><p>The <code>metadata</code> element functions as a generic container for metadata
-information.</p><p>Metadata information may be expressed by a <code>metadata</code> element
-in one of two (non-mutually exclusive) manners: (1) by specifying one
-or more metadata attributes on the <code>metadata</code>
-element, and (2) by specifying one
-or more child elements
-in the <code>metadata</code> element
-that express metadata. Both types of metadata
-are referred to in this document as <em>metadata items</em>.</p><table summary="HTML Table" id="elt-syntax-metadata" class="syntax"><caption>XML Representation – Element Information Item: metadata</caption><tbody><tr><td>
+<h4><a id="metadata-vocabulary-metadata"></a>12.1.1 metadata</h4><p>The <code>metadata</code> element functions as a generic container for metadata
+information.</p><p>Metadata information may be expressed with a <code>metadata</code> element by specifying
+(1) one or more metadata attributes on the <code>metadata</code> element,
+(2) one or more metadata child elements in the <code>metadata</code> element, or
+(3) a combination of metadata attributes and metadata child elements.  Both types
+of metadata information are referred to in this document as <em>metadata
+items</em>.</p><a id="elt-syntax-metadata"></a><table class="syntax"><caption>XML Representation – Element Information Item: metadata</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;metadata
   <a href="#content-attribute-id">xml:id</a> = ID
@@ -4448,12 +4640,11 @@
 &lt;/metadata&gt;
 </pre></div>
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>The meaning of a specific metadata item must be evaluated in the
-context of where it appears. The core vocabulary catalog permits an
-arbitrary number of <code>metadata</code> element children of any
-content element type except for the
-<code>tt</code> element. See specific element
+context where it appears. The core vocabulary catalog permits an
+arbitrary number of <code>metadata</code> element children on any
+content element type except for the <code>tt</code> element. See specific element
 vocabulary definitions for any constraints that apply to such
-usage.</p></div><p>The use of document metadata is illustrated by the following example.</p><table summary="HTML Table" id="metadata-vocabulary-metadata-example-1" class="example"><caption>Example Fragment – Document Metadata</caption><tbody><tr><td>
+usage.</p></div><p>The use of document metadata is illustrated by the following example.</p><a id="metadata-vocabulary-metadata-example-1"></a><table class="example"><caption>Example Fragment – Document Metadata</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ...
 &lt;head&gt;
@@ -4464,7 +4655,7 @@
 &lt;/head&gt;
 ...
 </pre></div>
-</td></tr></tbody></table><p/><p>The use of element metadata is illustrated by the following example.</p><table summary="HTML Table" id="metadata-vocabulary-metadata-example-2" class="example"><caption>Example Fragment – Element Metadata</caption><tbody><tr><td>
+</td></tr></tbody></table><p></p><p>The use of element metadata is illustrated by the following example.</p><a id="metadata-vocabulary-metadata-example-2"></a><table class="example"><caption>Example Fragment – Element Metadata</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ...
 &lt;div&gt;
@@ -4475,10 +4666,10 @@
 &lt;/div&gt;
 ...
 </pre></div>
-</td></tr></tbody></table><p/><p>The use of metadata attribute items is illustrated by the following example.</p><table summary="HTML Table" id="metadata-vocabulary-metadata-example-3" class="example"><caption>Example Fragment – Foreign Metadata Attribute Items</caption><tbody><tr><td>
+</td></tr></tbody></table><p></p><p>The use of metadata attribute items is illustrated by the following example.</p><a id="metadata-vocabulary-metadata-example-3"></a><table class="example"><caption>Example Fragment – Foreign Metadata Attribute Items</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ...
-&lt;div xmlns:ext="http://foo.bar.example.org/ttaf1#metadata"&gt;
+&lt;div xmlns:ext="http://example.org/ttml#metadata"&gt;
   &lt;metadata ext:ednote="remove this division prior to publishing"/&gt;
 &lt;/div&gt;
 ...
@@ -4489,7 +4680,7 @@
 attribute may also be expressed directly on the <code>div</code> element;
 however, in this case the author wishes to segregate certain metadata
 attributes by expressing them indirectly on <code>metadata</code>
-elements.</p></div><p/><p>The use of foreign element metadata is illustrated by the following example.</p><table summary="HTML Table" id="metadata-vocabulary-metadata-example-4" class="example"><caption>Example Fragment – Foreign Element Metadata</caption><tbody><tr><td>
+elements.</p></div><p></p><p>The use of foreign element metadata is illustrated by the following example.</p><a id="metadata-vocabulary-metadata-example-4"></a><table class="example"><caption>Example Fragment – Foreign Element Metadata</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ...
 &lt;metadata
@@ -4503,9 +4694,9 @@
 ...
 </pre></div>
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the above example, a number of elements defined by the Dublin
-Core metadata vocabulary are used to express document level metadata.</p></div><p/></div><div class="div3">
-<h4><a name="metadata-vocabulary-title" id="metadata-vocabulary-title"/>12.1.2 ttm:title</h4><p>The <code>ttm:title</code> element is used to express a human-readable title of
-a specific element instance.</p><table summary="HTML Table" id="elt-syntax-metadata-title" class="syntax"><caption>XML Representation – Element Information Item: ttm:title</caption><tbody><tr><td>
+Core metadata vocabulary are used to express document level metadata.</p></div><p></p></div><div class="div3">
+<h4><a id="metadata-vocabulary-title"></a>12.1.2 ttm:title</h4><p>The <code>ttm:title</code> element is used to express a human-readable title of
+a specific element instance.</p><a id="elt-syntax-metadata-title"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttm:title</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttm:title
   <a href="#content-attribute-id">xml:id</a> = ID
@@ -4518,8 +4709,8 @@
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>No specific use of the <code>ttm:title</code> element is defined by this specification.</p></div><p>Examples of the <code>ttm:title</code> element are shown above in
 <a href="#metadata-vocabulary-metadata-example-1"><b>Example Fragment – Document Metadata</b></a> and
 <a href="#metadata-vocabulary-metadata-example-2"><b>Example Fragment – Element Metadata</b></a>.</p></div><div class="div3">
-<h4><a name="metadata-vocabulary-desc" id="metadata-vocabulary-desc"/>12.1.3 ttm:desc</h4><p>The <code>ttm:desc</code> element is used to express a human-readable description of
-a specific element instance.</p><table summary="HTML Table" id="elt-syntax-metadata-desc" class="syntax"><caption>XML Representation – Element Information Item: ttm:desc</caption><tbody><tr><td>
+<h4><a id="metadata-vocabulary-desc"></a>12.1.3 ttm:desc</h4><p>The <code>ttm:desc</code> element is used to express a human-readable description of
+a specific element instance.</p><a id="elt-syntax-metadata-desc"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttm:desc</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttm:desc
   <a href="#content-attribute-id">xml:id</a> = ID
@@ -4532,9 +4723,9 @@
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>No specific use of the <code>ttm:desc</code> element is defined by this specification.</p></div><p>Examples of the <code>ttm:desc</code> element are shown above in
 <a href="#metadata-vocabulary-metadata-example-1"><b>Example Fragment – Document Metadata</b></a> and
 <a href="#metadata-vocabulary-metadata-example-2"><b>Example Fragment – Element Metadata</b></a>.</p></div><div class="div3">
-<h4><a name="metadata-vocabulary-copyright" id="metadata-vocabulary-copyright"/>12.1.4 ttm:copyright</h4><p>The <code>ttm:copyright</code> element is used to express a human-readable copyright that
+<h4><a id="metadata-vocabulary-copyright"></a>12.1.4 ttm:copyright</h4><p>The <code>ttm:copyright</code> element is used to express a human-readable copyright that
 applies to some scoping level.</p><p>A copyright statement that applies to a document as a whole should appear as a
-child of the <code>head</code> element.</p><table summary="HTML Table" id="elt-syntax-metadata-copyright" class="syntax"><caption>XML Representation – Element Information Item: ttm:copyright</caption><tbody><tr><td>
+child of the <code>head</code> element.</p><a id="elt-syntax-metadata-copyright"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttm:copyright</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttm:copyright
   <a href="#content-attribute-id">xml:id</a> = ID
@@ -4545,10 +4736,10 @@
 &lt;/ttm:copyright&gt;
 </pre></div>
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>No specific use of the <code>ttm:copyright</code> element is defined by this specification.</p></div></div><div class="div3">
-<h4><a name="metadata-vocabulary-agent" id="metadata-vocabulary-agent"/>12.1.5 ttm:agent</h4><p>The <code>ttm:agent</code> element is used to define an agent for the purpose of associating
+<h4><a id="metadata-vocabulary-agent"></a>12.1.5 ttm:agent</h4><p>The <code>ttm:agent</code> element is used to define an agent for the purpose of associating
 content information with an agent who is involved in the production or expression of that content.</p><p>The <code>ttm:agent</code> element accepts as its children zero or more <code>ttm:name</code> elements followed by
 zero or one <code>ttm:actor</code> element.</p><p>At least one <code>ttm:name</code> element child should be specified that expresses a name for the
-agent, whether it be the name of a person, character, group, or organization.</p><table summary="HTML Table" id="elt-syntax-metadata-agent" class="syntax"><caption>XML Representation – Element Information Item: ttm:agent</caption><tbody><tr><td>
+agent, whether it be the name of a person, character, group, or organization.</p><a id="elt-syntax-metadata-agent"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttm:agent</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttm:agent
   <span class="reqattr">type</span> = (<em>person</em>|<em>character</em>|<em>group</em>|<em>organization</em>|<em>other</em>)
@@ -4567,7 +4758,7 @@
 <code>metadata</code> element child of the <code>head</code> element.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>A <code>ttm:agent</code> element instance is typically referenced using a <code>ttm:agent</code>
 attribute on a content element.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>If a character agent is played by multiple actors, then multiple character
 agents may be specified (and referenced) wherein different definitions of the
-character specify different actors.</p></div><p>The use of agent metadata is illustrated by the following example.</p><table summary="HTML Table" id="metadata-vocabulary-agent-example-1" class="example"><caption>Example Fragment – Agent Metadata</caption><tbody><tr><td>
+character specify different actors.</p></div><p>The use of agent metadata is illustrated by the following example.</p><a id="metadata-vocabulary-agent-example-1"></a><table class="example"><caption>Example Fragment – Agent Metadata</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 
 &lt;tt xml:lang="en" xmlns="http://www.w3.org/ns/ttml" xmlns:ttm="http://www.w3.org/ns/ttml#metadata"&gt;
@@ -4603,8 +4794,8 @@
 the <code>ttm:agent</code> metadata items are specified as immediate
 children of the document's <code>head</code> element rather than being
 placed in a container <code>metadata</code> element.</p></div></div><div class="div3">
-<h4><a name="metadata-vocabulary-name" id="metadata-vocabulary-name"/>12.1.6 ttm:name</h4><p>The <code>ttm:name</code> element is used to specify a name of a person, character,
-group, or organization.</p><table summary="HTML Table" id="elt-syntax-metadata-name" class="syntax"><caption>XML Representation – Element Information Item: ttm:name</caption><tbody><tr><td>
+<h4><a id="metadata-vocabulary-name"></a>12.1.6 ttm:name</h4><p>The <code>ttm:name</code> element is used to specify a name of a person, character,
+group, or organization.</p><a id="elt-syntax-metadata-name"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttm:name</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttm:name
   <span class="reqattr">type</span> = (<em>full</em>|<em>family</em>|<em>given</em>|<em>alias</em>|<em>other</em>)
@@ -4619,8 +4810,8 @@
 if specified, must have one of the following values:</p><ul><li><p><code>full</code></p></li><li><p><code>family</code></p></li><li><p><code>given</code></p></li><li><p><code>alias</code></p></li><li><p><code>other</code></p></li></ul><p>The relationship between the type of a name and the syntactic expression of the name
 is not defined by this specification.</p><p>Two examples of the <code>ttm:name</code> element are shown above in
 <a href="#metadata-vocabulary-agent-example-1"><b>Example Fragment – Agent Metadata</b></a>.</p></div><div class="div3">
-<h4><a name="metadata-vocabulary-actor" id="metadata-vocabulary-actor"/>12.1.7 ttm:actor</h4><p>The <code>ttm:actor</code> element is used to link the definition of a (role-based) character
-agent with another agent that portrays the character.</p><table summary="HTML Table" id="elt-syntax-metadata-actor" class="syntax"><caption>XML Representation – Element Information Item: ttm:actor</caption><tbody><tr><td>
+<h4><a id="metadata-vocabulary-actor"></a>12.1.7 ttm:actor</h4><p>The <code>ttm:actor</code> element is used to link the definition of a (role-based) character
+agent with another agent that portrays the character.</p><a id="elt-syntax-metadata-actor"></a><table class="syntax"><caption>XML Representation – Element Information Item: ttm:actor</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 &lt;ttm:actor
   <span class="reqattr">agent</span> = IDREF
@@ -4632,28 +4823,28 @@
 &lt;/ttm:actor&gt;
 </pre></div>
 </td></tr></tbody></table><p>The <code>agent</code> attribute of a <code>ttm:actor</code> element must
-reference a <code>ttm:agent</code> element that denotes the person,
+reference a <em>significant</em> <code>ttm:agent</code> element that denotes the person,
 group, or organization acting the part of a character.</p><p>An example of the <code>ttm:actor</code> element is shown above in
 <a href="#metadata-vocabulary-agent-example-1"><b>Example Fragment – Agent Metadata</b></a>.</p></div></div><div class="div2">
-<h3><a name="metadata-attribute-vocabulary" id="metadata-attribute-vocabulary"/>12.2 Metadata Attribute Vocabulary</h3><p>This section specifies the following attributes in the TT Metadata Namespace
+<h3><a id="metadata-attribute-vocabulary"></a>12.2 Metadata Attribute Vocabulary</h3><p>This section specifies the following attributes in the TT Metadata Namespace
 for use with the <code>metadata</code> element and with certain content elements:</p><ul><li><p><a href="#metadata-attribute-agent"><b>12.2.1 ttm:agent</b></a></p></li><li><p><a href="#metadata-attribute-role"><b>12.2.2 ttm:role</b></a></p></li></ul><div class="note"><p class="prefix"><b>Note:</b></p><p>Only certain metadata item attributes may be used with content elements. See
 the definitions of content elements to determine permissible usage.</p></div><div class="div3">
-<h4><a name="metadata-attribute-agent" id="metadata-attribute-agent"/>12.2.1 ttm:agent</h4><p>The <code>ttm:agent</code> attribute takes an <code>IDREFS</code>
+<h4><a id="metadata-attribute-agent"></a>12.2.1 ttm:agent</h4><p>The <code>ttm:agent</code> attribute takes an <code>IDREFS</code>
 value, and is used with certain content elements to designate the
 agents that perform or are
-involved in the performance of the content.</p><p>If specified, a <code>ttm:agent</code> attribute must reference
+involved in the performance of the content.</p><p>If specified, a <code>ttm:agent</code> attribute must reference <em>significant</em>
 <code>ttm:agent</code> element instances that appear
-as a descendent of the same document instance as
-that of the referring element.</p><p>An example of the <code>ttm:agent</code> attribute is shown above in
+as a descendent of the same <em>Document Instance</em> as
+that of the referring element.</p><p>The same IDREF, <em>ID</em>, should not appear more than once in the value of a <code>ttm:agent</code> attribute.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>This constraint is intended to discourage the use of redundant agent references.</p></div><p>An example of the <code>ttm:agent</code> attribute is shown above in
 <a href="#metadata-vocabulary-agent-example-1"><b>Example Fragment – Agent Metadata</b></a>.</p></div><div class="div3">
-<h4><a name="metadata-attribute-role" id="metadata-attribute-role"/>12.2.2 ttm:role</h4><p>The <code>ttm:role</code> attribute may be used by a content author
+<h4><a id="metadata-attribute-role"></a>12.2.2 ttm:role</h4><p>The <code>ttm:role</code> attribute may be used by a content author
 to express
 the roles, functions, or characteristics
 of some content element that is so labeled.</p><p>If specified, the value of this attribute must adhere to the following
 syntax, where
 the syntactic element <em>S</em> must adhere to production
-[3] <code>S</code> as defined by <a href="#xml10">[XML 1.0]</a> §
-2.3:</p><table summary="HTML Table" id="metadata-attribute-role-syntax" class="syntax"><caption>Syntax Representation – ttm:role</caption><tbody><tr><td>
+[3] <code>S</code> as defined by <a href="#xml10">[XML 1.0]</a>&nbsp;§
+2.3:</p><a id="metadata-attribute-role-syntax"></a><table class="syntax"><caption>Syntax Representation – ttm:role</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttm:role
   role ( <em>S</em> role )*
@@ -4684,2136 +4875,80 @@
 token-char
   : { XML NameChar }    // XML 1.1 Production [4a]
 </pre></div>
-</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>All values of <code>ttm:role</code> that do not start with the prefix
-<code>x-</code> are reserved for future standardization.</p></div></div></div></div></div><div class="back"><div class="div1">
-<h2><a name="reduced-infoset" id="reduced-infoset"/>A Reduced XML Infoset</h2><p><em>This appendix is normative.</em></p><p>For the purposes of this specification, a Reduced XML Infoset is
+</td></tr></tbody></table><p>The same <code>role</code> token, <em>R</em>, should not appear more than once in the value of a <code>ttm:role</code> attribute.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>This constraint is intended to discourage the use of redundant role tokens.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>All values of <code>ttm:role</code> that do not start with the prefix
+<code>x-</code> are reserved for future standardization.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>If using a custom <code>x-</code> prefixed form of <code>ttm:role</code>, it
+is recommended that an organization unique infix be used as well in order to
+prevent collisions. For example, <code>x-example-org-custom-role</code>. Furthermore,
+a registry for role values is available at
+<a href="http://www.w3.org/wiki/TTML/RoleRegistry">http://www.w3.org/wiki/TTML/RoleRegistry</a>
+in order to promote interoperability and collision avoidance.</p></div></div></div></div></div><div class="back"><div class="div1">
+<h2><a id="reduced-infoset"></a>A Reduced XML Infoset</h2><p><em>This appendix is normative.</em></p><p>For the purposes of this specification, a <em>Reduced XML Infoset</em> is
 an XML Information Set <a href="#infoset">[XML InfoSet]</a> that consists of only the following information items
 and information item properties:</p><div class="div2">
-<h3><a name="reduced-infoset-document" id="reduced-infoset-document"/>A.1 Document Information Item</h3><ul><li><p><code>[document element]</code></p></li></ul></div><div class="div2">
-<h3><a name="reduced-infoset-element" id="reduced-infoset-element"/>A.2 Element Information Item</h3><ul><li><p><code>[namespace URI]</code></p></li><li><p><code>[local name]</code></p></li><li><p><code>[children]</code></p></li><li><p><code>[attributes]</code></p></li></ul><p>Child information items <code>[children]</code> are reduced to 
+<h3><a id="reduced-infoset-document"></a>A.1 Document Information Item</h3><ul><li><p><code>[document element]</code></p></li></ul></div><div class="div2">
+<h3><a id="reduced-infoset-element"></a>A.2 Element Information Item</h3><ul><li><p><code>[namespace URI]</code></p></li><li><p><code>[local name]</code></p></li><li><p><code>[children]</code></p></li><li><p><code>[attributes]</code></p></li></ul><p>Child information items <code>[children]</code> are reduced to 
 only element and character information items.</p></div><div class="div2">
-<h3><a name="reduced-infoset-attribute" id="reduced-infoset-attribute"/>A.3 Attribute Information Item</h3><ul><li><p><code>[namespace URI]</code></p></li><li><p><code>[local name]</code></p></li><li><p><code>[normalized value]</code></p></li></ul></div><div class="div2">
-<h3><a name="reduced-infoset-character" id="reduced-infoset-character"/>A.4 Character Information Item</h3><ul><li><p><code>[character code]</code></p></li></ul><p>Contiguous character information items are not required to be represented distinctly,
+<h3><a id="reduced-infoset-attribute"></a>A.3 Attribute Information Item</h3><ul><li><p><code>[namespace URI]</code></p></li><li><p><code>[local name]</code></p></li><li><p><code>[normalized value]</code></p></li></ul></div><div class="div2">
+<h3><a id="reduced-infoset-character"></a>A.4 Character Information Item</h3><ul><li><p><code>[character code]</code></p></li></ul><p>Contiguous character information items are not required to be represented distinctly,
 but may be aggregated (chunked) into a sequence of character codes (i.e., a character string).</p></div></div><div class="div1">
-<h2><a name="schemas" id="schemas"/>B Schemas</h2><p><em>This appendix is normative.</em></p><p>This appendix specifies the following schemas for use with
-DFXP Content document instances:</p><ul><li><p>Relax NG, Compact Syntax (RNC) Schema</p></li><li><p>XML Schema Definition (XSD) Schema</p></li></ul><p>In any case where a schema specified by this appendix differs from the
+<h2><a id="schemas"></a>B Schemas</h2><p><em>This appendix is normative.</em></p><p>This appendix specifies the following schemas for use with
+<em>Document Instances</em>:</p><ul><li><p>Relax NG, Compact Syntax (RNC) Schema</p></li><li><p>XML Schema Definition (XSD) Schema</p></li></ul><p>In any case where a schema specified by this appendix differs from the
 normative definitions of document type, element type, or attribute type
 as defined by the body of this specification, then the body of this
 specification takes precedence.</p><div class="div2">
-<h3><a name="dfxp-schema-rnc" id="dfxp-schema-rnc"/>B.1 Relax NG Schema</h3><p>This section specifies a Relax NG Compact Syntax (RNC) <a href="#rng">[RELAX NG]</a> based schema
-for DFXP Content, also available in a <a href="rnc/schema.zip">ZIP
-Archive</a>.</p><div class="div3">
-<h4><a name="rnc-dfxp-driver-schema" id="rnc-dfxp-driver-schema"/>B.1.1 Driver</h4><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 Distribution Format Exchange Profile (DFXP) Schema ..........
-# .......................................................................
-
-# default namespace
-default namespace tt = "http://www.w3.org/ns/ttml"
-
-# generic tt modules
-include "ttaf1-dfxp-datatypes.rnc"
-include "ttaf1-dfxp-classes.rnc"
-include "ttaf1-dfxp-core-attribs.rnc"
-include "ttaf1-dfxp-parameter-attribs.rnc"
-include "ttaf1-dfxp-metadata-attribs.rnc"
-include "ttaf1-dfxp-styling-attribs.rnc"
-include "ttaf1-dfxp-timing-attribs.rnc"
-include "ttaf1-dfxp-parameter-items.rnc"
-include "ttaf1-dfxp-parameters.rnc"
-include "ttaf1-dfxp-metadata-items.rnc"
-include "ttaf1-dfxp-metadata.rnc"
-include "ttaf1-dfxp-styling.rnc"
-include "ttaf1-dfxp-animation.rnc"
-include "ttaf1-dfxp-layout.rnc"
-include "ttaf1-dfxp-content.rnc"
-include "ttaf1-dfxp-head.rnc"
-include "ttaf1-dfxp-document.rnc"
-
-start = TTAF.tt | TTAF.parameters.profile
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div3">
-<h4><a name="rnc-dfxp-modules" id="rnc-dfxp-modules"/>B.1.2 Modules</h4><div class="div4">
-<h5><a name="rnc-dfxp-animation-module" id="rnc-dfxp-animation-module"/>B.1.2.1 Animation Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Animation Module .......................................
-# .......................................................................
-
-# set - discrete animation
-TTAF.set =
-  element set {
-    TTAF.set.attlist,
-    TTAF.set.content
-  }
-
-TTAF.set.attlist &amp;=
-  TTAF.Core.attrib.class,
-  TTAF.Timed.attrib.class,
-  (TTAF.Styling.attrib.class |
-   TTAF.Styling.ForeignExtension.attrib+ )
-
-TTAF.set.content.extra = empty
-TTAF.set.content =
-  (TTAF.Metadata.class*,
-   TTAF.set.content.extra*)
-
-TTAF.Animation.extra = empty
-TTAF.Animation.class |=
-  TTAF.set |
-  TTAF.Animation.extra
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-classes-module" id="rnc-dfxp-classes-module"/>B.1.2.2 Classes Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Class Declarations Module ..............................
-# .......................................................................
-
-# attribute group classes
-TTAF.Core.attrib.class = empty
-TTAF.Metadata.attrib.class = empty
-TTAF.Parameter.attrib.class = empty
-TTAF.RegionBinding.attrib.class = empty
-TTAF.StyleBinding.attrib.class = empty
-TTAF.Styled.attrib.class = empty
-TTAF.Styling.attrib.class = empty
-TTAF.Timed.attrib.class = empty
-TTAF.TimedContainer.attrib.class = empty
-TTAF.TimingInterval.attrib.class = empty
-
-# element group classes
-TTAF.Animation.class = empty
-TTAF.Block.class = empty
-TTAF.BlockNoDiv.class = empty
-TTAF.Inline.class = empty
-TTAF.InlineNoSpan.class = empty
-TTAF.MetadataNoAgent.class = empty
-TTAF.Metadata.class = empty
-TTAF.MetadataItems.class = empty
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-content-module" id="rnc-dfxp-content-module"/>B.1.2.3 Content Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Content Module .........................................
-# .......................................................................
-
-# body - content body
-TTAF.body =
-  element body {
-    TTAF.body.attlist,
-    TTAF.body.content
-  }
-
-TTAF.body.attlist &amp;=
-  TTAF.Core.attrib.class,
-  TTAF.Metadata.attrib.class,
-  TTAF.RegionBinding.attrib.class,
-  TTAF.Styled.attrib.class,
-  TTAF.TimedContainer.attrib.class
-
-TTAF.body.content.extra = empty
-TTAF.body.content =
-  (TTAF.Metadata.class*,
-   TTAF.Animation.class*,
-   (TTAF.Block.class | TTAF.body.content.extra)*)
-
-# div - division
-TTAF.div =
-  element div {
-    TTAF.div.attlist,
-    TTAF.div.content
-  }
-
-TTAF.div.attlist &amp;=
-  TTAF.Core.attrib.class,
-  TTAF.Metadata.attrib.class,
-  TTAF.RegionBinding.attrib.class,
-  TTAF.Styled.attrib.class,
-  TTAF.TimedContainer.attrib.class
-
-TTAF.div.content.extra = empty
-TTAF.div.content =
-  (TTAF.Metadata.class*,
-   TTAF.Animation.class*,
-   (TTAF.Block.class | TTAF.div.content.extra)*)
-
-# p - paragraph
-TTAF.p =
-  element p {
-    TTAF.p.attlist,
-    TTAF.p.content
-  }
-
-TTAF.p.attlist &amp;=
-  TTAF.Core.attrib.class,
-  TTAF.Metadata.attrib.class,
-  TTAF.RegionBinding.attrib.class,
-  TTAF.Styled.attrib.class,
-  TTAF.TimedContainer.attrib.class
-
-TTAF.p.content.extra = empty
-TTAF.p.content =
-  (TTAF.Metadata.class*,
-   TTAF.Animation.class*,
-   (TTAF.Inline.class |
-    TTAF.p.content.extra)*)
-
-# span - intra-paragraph inline span
-TTAF.span =
-  element span {
-    TTAF.span.attlist,
-    TTAF.span.content
-  }
-
-TTAF.span.attlist &amp;=
-  TTAF.Core.attrib.class,
-  TTAF.Metadata.attrib.class,
-  TTAF.RegionBinding.attrib.class,
-  TTAF.Styled.attrib.class,
-  TTAF.TimedContainer.attrib.class
-
-TTAF.span.content.extra = empty
-TTAF.span.content =
-  (TTAF.Metadata.class*,
-   TTAF.Animation.class*,
-   (TTAF.Inline.class |
-    TTAF.span.content.extra)*)
-
-# br - manual line break
-TTAF.br =
-  element br {
-    TTAF.br.attlist,
-    TTAF.br.content
-  }
-
-TTAF.br.attlist &amp;=
-  TTAF.Core.attrib.class,
-  TTAF.Metadata.attrib.class,
-  TTAF.Styled.attrib.class
-
-TTAF.br.content.extra = empty
-TTAF.br.content =
-  (TTAF.Metadata.class*,
-   TTAF.Animation.class*,
-   TTAF.br.content.extra*)
-
-# Block.class
-TTAF.Block.extra = empty
-TTAF.BlockNoDiv.class |=
-  TTAF.p | TTAF.Block.extra
-TTAF.Block.class |=
-  TTAF.div | TTAF.BlockNoDiv.class
-
-# Inline.class
-TTAF.Inline.extra = empty
-TTAF.InlineNoSpan.class |=
-  text | TTAF.br | TTAF.Inline.extra
-TTAF.Inline.class |=
-  TTAF.span | TTAF.InlineNoSpan.class
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-core-attribs-module" id="rnc-dfxp-core-attribs-module"/>B.1.2.4 Core Attributes Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Core Attributes Module .................................
-# .......................................................................
-
-TTAF.id.attrib
-  = attribute xml:id { xsd:ID }?
-
-TTAF.lang.attrib
-  = attribute xml:lang { TTAF.LanguageCode.datatype }?
-
-TTAF.lang.required.attrib
-  = attribute xml:lang { TTAF.LanguageCode.datatype }
-
-TTAF.space.attrib
-  = attribute xml:space { TTAF.XMLSpace.datatype }?
-
-TTAF.Core.extra.attrib
-  = empty
-
-TTAF.Core.attrib.class &amp;=
-  TTAF.id.attrib,
-  TTAF.lang.attrib,
-  TTAF.space.attrib,
-  TTAF.Core.extra.attrib
-
-TTAF.Core.required.attrib.class &amp;=
-  TTAF.id.attrib,
-  TTAF.lang.required.attrib,
-  TTAF.space.attrib,
-  TTAF.Core.extra.attrib
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-datatypes-module" id="rnc-dfxp-datatypes-module"/>B.1.2.5 Data Types Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Datatypes Module .......................................
-# .......................................................................
-
-TTAF.Alpha.datatype =
-  xsd:float { minInclusive = "0" maxInclusive = "1" }
-
-TTAF.Agent.datatype =
-  xsd:IDREFS
-
-TTAF.CellResolution.datatype =
-  string
-
-TTAF.ClockMode.datatype =
-  "local" |
-  "gps" |
-  "utc"
-
-TTAF.Color.datatype =
-  string
-
-TTAF.Direction.datatype =
-  "ltr" |
-  "rtl"
-
-TTAF.Display.datatype =
-  "auto" |
-  "none"
-
-TTAF.DisplayAlign.datatype =
-  "before" |
-  "center" |
-  "after"
-
-TTAF.DropMode.datatype =
-  "dropNTSC" |
-  "dropPAL" |
-  "nonDrop"
-
-TTAF.ExtensionDesignator.datatype =
-  TTAF.URI.datatype
-
-TTAF.ExtensionValue.datatype =
- "optional" |
- "required" |
- "use"
-
-TTAF.Extent.datatype =
-  string
-
-TTAF.FeatureDesignator.datatype =
-  TTAF.URI.datatype
-
-TTAF.FeatureValue.datatype =
- "optional" |
- "required" |
- "use"
-
-TTAF.FontFamily.datatype =
-  string
-
-TTAF.FontSize.datatype =
-  string
-
-TTAF.FontStyle.datatype =
-  "normal" |
-  "italic" |
-  "oblique"
-
-TTAF.FontWeight.datatype =
-  "normal" |
-  "bold"
-
-TTAF.FrameRate.datatype =
-  xsd:nonNegativeInteger
-
-TTAF.FrameRateMultiplier.datatype =
-  xsd:string { pattern = "\p{Nd}+\s+\p{Nd}+" }
-
-TTAF.LanguageCode.datatype =
-  xsd:NMTOKEN
-
-TTAF.LineHeight.datatype =
-  string
-
-TTAF.MarkerMode.datatype =
-  "continuous" |
-  "discontinuous"
-
-TTAF.MetadataAgentType.datatype =
-  "person" |
-  "character" |
-  "group" |
-  "organization" |
-  "other"
-
-TTAF.MetadataNameType.datatype =
-  "full" |
-  "family" |
-  "given" |
-  "alias" |
-  "other"
-
-TTAF.MetadataRoleBaseType.datatype =
-  "action" |
-  "caption" |
-  "description" |
-  "dialog" |
-  "expletive" |
-  "kinesic" |
-  "lyrics" |
-  "music" |
-  "narration" |
-  "quality" |
-  "sound" |
-  "source" |
-  "suppressed" |
-  "reproduction" |
-  "thought" |
-  "title" |
-  "transcription"
-
-TTAF.Opacity.datatype =
-  string
-
-TTAF.Origin.datatype =
-  string
-
-TTAF.Overflow.datatype =
-  "visible" |
-  "hidden" 
-
-TTAF.Padding.datatype =
-  string
-
-TTAF.PixelAspectRatio.datatype =
-  xsd:string { pattern = "\p{Nd}+\s+\p{Nd}+" }
-
-TTAF.Profile.datatype =
-  TTAF.URI.datatype
-
-TTAF.Role.datatype =
-  xsd:NMTOKENS
-
-TTAF.ShowBackground.datatype =
-  "always" |
-  "whenActive"
-
-TTAF.SubFrameRate.datatype =
-  xsd:positiveInteger
-
-TTAF.TextAlign.datatype =
-  "left" |
-  "center" |
-  "right" |
-  "start" |
-  "end"
-
-TTAF.TextDecoration.datatype =
-  "none" |
-  "underline" |
-  "noUnderline" |
-  "overline" |
-  "noOverline" |
-  "lineThrough" |
-  "noLineThrough"
-
-TTAF.TextOutline.datatype =
-  string
-
-TTAF.TickRate.datatype =
-  xsd:positiveInteger
-
-TTAF.TimeBase.datatype =
-  "media" |
-  "smpte" |
-  "clock"
-
-TTAF.TimeContainer.datatype =
-  "par" |
-  "seq"
-
-TTAF.TimeCoordinate.datatype =
-  string
-
-TTAF.TimeDuration.datatype =
-  string
-
-TTAF.URI.datatype =
-  xsd:anyURI
-
-TTAF.UnicodeBidi.datatype =
-  "normal" |
-  "embed" |
-  "bidiOverride"
-
-TTAF.Visibility.datatype =
-  "hidden" |
-  "visible"
-
-TTAF.WrapOption.datatype =
-  "wrap" |
-  "noWrap"
-
-TTAF.WritingMode.datatype =
-  "lrtb" |
-  "rltb" |
-  "tbrl" |
-  "tblr" |
-  "lr" |
-  "rl" |
-  "tb"
-
-TTAF.XMLSpace.datatype =
-  "default" |
-  "preserve"
-
-TTAF.ZIndex.datatype =
-  string
-  
-# .......................................................................
-# .......................................................................
-# .......................................................................
-
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-document-module" id="rnc-dfxp-document-module"/>B.1.2.6 Document Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Document Module ........................................
-# .......................................................................
-
-## tt - generic top-level document element type
-TTAF.tt =
-  element tt {
-    TTAF.tt.attlist,
-    TTAF.tt.content
-  }
-
-TTAF.tt.attlist &amp;=
-  TTAF.Core.required.attrib.class,
-  TTAF.Parameter.attrib.class,
-  TTAF.extent.attrib
-
-TTAF.tt.content =
-  (TTAF.head?, TTAF.body?)
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-head-module" id="rnc-dfxp-head-module"/>B.1.2.7 Header Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Header Module ..........................................
-# .......................................................................
-
-# head - generic header
-TTAF.head =
-  element head {
-    TTAF.head.attlist,
-    TTAF.head.content
-  }
-
-TTAF.head.attlist &amp;=
-  TTAF.Core.attrib.class
-
-TTAF.head.content.extra = empty
-TTAF.head.content =
-  (TTAF.Metadata.class*,
-   TTAF.Parameters.class*,
-   TTAF.styling?,
-   TTAF.layout?,
-   TTAF.head.content.extra*)
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-layout-module" id="rnc-dfxp-layout-module"/>B.1.2.8 Layout Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Layout Module ..........................................
-# .......................................................................
-
-# region reference attribute; must reference /head/layout/region
-TTAF.region.attrib
-  = attribute region { xsd:IDREF }?
-
-# region binding attribute class
-TTAF.RegionBinding.attrib.class &amp;=
-  TTAF.region.attrib
-
-# layout - generic layout container
-TTAF.layout =
-  element layout {
-    TTAF.layout.attlist,
-    TTAF.layout.content
-  }
-
-TTAF.layout.attlist &amp;=
-  TTAF.Core.attrib.class
-
-TTAF.layout.content.extra = empty
-TTAF.layout.content =
-  (TTAF.Metadata.class*,
-   TTAF.layout.region*,
-   TTAF.layout.content.extra*)
-
-# region - region declaration
-TTAF.layout.region =
-  element region {
-    TTAF.layout.region.attlist,
-    TTAF.layout.region.content
-  }
-
-TTAF.layout.region.attlist &amp;=
-  TTAF.Core.attrib.class,
-  TTAF.TimedContainer.attrib.class,
-  TTAF.style.attrib,
-  (TTAF.Styling.attrib.class |
-   TTAF.Styling.ForeignExtension.attrib+ )
-
-TTAF.layout.region.content.extra = empty
-TTAF.layout.region.content =
-  (TTAF.Metadata.class*,
-   TTAF.Animation.class*,
-   TTAF.styling.style*,
-   TTAF.layout.region.content.extra*)
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-metadata-module" id="rnc-dfxp-metadata-module"/>B.1.2.9 Metadata Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Metadata Module ........................................
-# .......................................................................
-
-# namespace prefix bindings
-namespace tt = "http://www.w3.org/ns/ttml"
-namespace ttm = "http://www.w3.org/ns/ttml#metadata"
-namespace local = ""
-
-# meta - generic metadata
-TTAF.metadata =
-  element metadata {
-    TTAF.metadata.attlist,
-    TTAF.metadata.content
-  }
-
-TTAF.metadata.attlist &amp;=
-  TTAF.Core.attrib.class
-
-TTAF.External.class =
-  element * - ( tt:* | ttm:* ) {
-    ( attribute * - ( xml:id ) { text }
-      | text
-      | TTAF.External.class
-    )*
-  }
-
-TTAF.metadata.content.extra = empty
-TTAF.metadata.content =
-  (TTAF.MetadataItems.class |
-   TTAF.External.class |
-   TTAF.metadata.content.extra)*
-
-TTAF.Metadata.class |=
-  TTAF.MetadataItems.class |
-  TTAF.metadata
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-metadata-items-module" id="rnc-dfxp-metadata-items-module"/>B.1.2.10 Metadata Items Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Metadata Items Module ......................................
-# .......................................................................
-
-namespace ttm = "http://www.w3.org/ns/ttml#metadata"
-
-## actor - specifies actor
-TTAF.meta.actor =
-  element ttm:actor {
-    TTAF.meta.actor.attlist,
-    TTAF.meta.actor.content
-  }
-
-TTAF.meta.actor.attlist &amp;=
-  TTAF.Core.attrib.class,
-  attribute agent { xsd:IDREF }
-
-TTAF.meta.actor.content.extra = empty
-TTAF.meta.actor.content = empty
-
-## agent - specifies agent
-TTAF.meta.agent =
-  element ttm:agent {
-    TTAF.meta.agent.attlist,
-    TTAF.meta.agent.content
-  }
-
-TTAF.meta.agent.attlist &amp;=
-  TTAF.Core.attrib.class,
-  attribute type { TTAF.MetadataAgentType.datatype }
-
-TTAF.meta.agent.content.extra = empty
-TTAF.meta.agent.content =
-  (TTAF.meta.name*,
-   TTAF.meta.actor?,
-   TTAF.meta.agent.content.extra*)
-
-## copyright - specifies copyright statement
-TTAF.meta.copyright =
-  element ttm:copyright {
-    TTAF.meta.copyright.attlist,
-    TTAF.meta.copyright.content
-  }
-
-TTAF.meta.copyright.attlist &amp;=
-  TTAF.Core.attrib.class
-
-TTAF.meta.copyright.content.extra = empty
-TTAF.meta.copyright.content = text
-
-## desc - specifies description
-TTAF.meta.desc =
-  element ttm:desc {
-    TTAF.meta.desc.attlist,
-    TTAF.meta.desc.content
-  }
-
-TTAF.meta.desc.attlist &amp;=
-  TTAF.Core.attrib.class
-
-TTAF.meta.desc.content.extra = empty
-TTAF.meta.desc.content = text
-
-## name - specifies name
-TTAF.meta.name =
-  element ttm:name {
-    TTAF.meta.name.attlist,
-    TTAF.meta.name.content
-  }
-
-TTAF.meta.name.attlist &amp;=
-  TTAF.Core.attrib.class,
-  attribute type { TTAF.MetadataNameType.datatype }
-
-TTAF.meta.name.content.extra = empty
-TTAF.meta.name.content = text
-
-## title - describes title
-TTAF.meta.title =
-  element ttm:title {
-    TTAF.meta.title.attlist,
-    TTAF.meta.title.content
-  }
-
-TTAF.meta.title.attlist &amp;=
-  TTAF.Core.attrib.class
-
-TTAF.meta.title.content.extra = empty
-TTAF.meta.title.content = text
-
-## MetadataItems.class
-TTAF.MetadataItems.extra = empty
-TTAF.MetadataItems.class |=
-  TTAF.meta.agent |
-  TTAF.meta.copyright |
-  TTAF.meta.desc |
-  TTAF.meta.title |
-  TTAF.MetadataItems.extra
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-metadata-attribs-module" id="rnc-dfxp-metadata-attribs-module"/>B.1.2.11 Metadata Attributes Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Metadata Attributes Module ..............................
-# .......................................................................
-
-namespace tt = "http://www.w3.org/ns/ttml"
-namespace ttm = "http://www.w3.org/ns/ttml#metadata"
-namespace local = ""
-
-# Standard Metadata Attributes
-
-TTAF.agent.attrib
-  = attribute ttm:agent { TTAF.Agent.datatype }?
-TTAF.role.attrib
-  = attribute ttm:role { TTAF.Role.datatype }?
-
-# Metadata Attribute Class
-
-TTAF.Metadata.attrib.class &amp;=
-  TTAF.agent.attrib,
-  TTAF.role.attrib
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-parameters-module" id="rnc-dfxp-parameters-module"/>B.1.2.12 Parameters Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Parameters Module ......................................
-# .......................................................................
-
-TTAF.Parameters.class |=
-  TTAF.ParameterItems.class
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-parameter-items-module" id="rnc-dfxp-parameter-items-module"/>B.1.2.13 Parameter Items Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Parameter Items Module .................................
-# .......................................................................
-
-namespace ttp = "http://www.w3.org/ns/ttml#parameter"
-
-# profile - profile definition or use declaration
-TTAF.parameters.profile =
-  element ttp:profile {
-    TTAF.parameters.profile.attlist,
-    TTAF.parameters.profile.content
-  }
-
-TTAF.parameters.profile.attlist &amp;=
-  TTAF.id.attrib,
-  attribute use { TTAF.Profile.datatype }?
-
-TTAF.parameters.profile.content.extra = empty
-TTAF.parameters.profile.content =
-  (TTAF.Metadata.class*,
-   TTAF.parameters.features*,
-   TTAF.parameters.extensions*,
-   TTAF.parameters.profile.content.extra*)
-
-# features - container for feature elements
-TTAF.parameters.features =
-  element ttp:features {
-    TTAF.parameters.features.attlist,
-    TTAF.parameters.features.content
-  }
-
-TTAF.parameters.features.attlist &amp;=
-  TTAF.id.attrib,
-  attribute xml:base { TTAF.URI.datatype }?
-
-TTAF.parameters.features.content.extra = empty
-TTAF.parameters.features.content =
-  (TTAF.Metadata.class*,
-   TTAF.parameters.feature*,
-   TTAF.parameters.features.content.extra*)
-
-# feature - feature requirements declaration
-TTAF.parameters.feature =
-  element ttp:feature {
-    TTAF.parameters.feature.attlist,
-    TTAF.parameters.feature.content
-  }
-
-TTAF.parameters.feature.attlist =
-  TTAF.id.attrib,
-  attribute value { TTAF.FeatureValue.datatype }?
-
-TTAF.parameters.feature.content =
-  TTAF.FeatureDesignator.datatype
-
-# extensions - container for extension elements
-TTAF.parameters.extensions =
-  element ttp:extensions {
-    TTAF.parameters.extensions.attlist,
-    TTAF.parameters.extensions.content
-  }
-
-TTAF.parameters.extensions.attlist &amp;=
-  TTAF.id.attrib,
-  attribute xml:base { TTAF.URI.datatype }?
-
-TTAF.parameters.extensions.content.extra = empty
-TTAF.parameters.extensions.content =
-  (TTAF.Metadata.class*,
-   TTAF.parameters.extension*,
-   TTAF.parameters.extensions.content.extra*)
-
-# extension - extension requirements declaration
-TTAF.parameters.extension =
-  element ttp:extension {
-    TTAF.parameters.extension.attlist,
-    TTAF.parameters.extension.content
-  }
-
-TTAF.parameters.extension.attlist =
-  TTAF.id.attrib,
-  attribute value { TTAF.ExtensionValue.datatype }?
-
-TTAF.parameters.extension.content =
-  TTAF.ExtensionDesignator.datatype
-
-## ParameterItems.class
-TTAF.ParameterItems.extra = empty
-TTAF.ParameterItems.class |=
-  TTAF.parameters.profile |
-  TTAF.ParameterItems.extra
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-parameter-attribs-module" id="rnc-dfxp-parameter-attribs-module"/>B.1.2.14 Parameter Attributes Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Parameter Attributes Module ............................
-# .......................................................................
-
-namespace ttp = "http://www.w3.org/ns/ttml#parameter"
-
-# Standard Metadata Attributes
-
-TTAF.cellResolution.attrib
-  = attribute ttp:cellResolution { TTAF.CellResolution.datatype }?
-TTAF.clockMode.attrib
-  = attribute ttp:clockMode { TTAF.ClockMode.datatype }?
-TTAF.dropMode.attrib
-  = attribute ttp:dropMode { TTAF.DropMode.datatype }?
-TTAF.frameRate.attrib
-  = attribute ttp:frameRate { TTAF.FrameRate.datatype }?
-TTAF.frameRateMultiplier.attrib
-  = attribute ttp:frameRateMultiplier { TTAF.FrameRateMultiplier.datatype }?
-TTAF.markerMode.attrib
-  = attribute ttp:markerMode { TTAF.MarkerMode.datatype }?
-TTAF.profile.attrib
-  = attribute ttp:profile { TTAF.Profile.datatype }?
-TTAF.pixelAspectRatio.attrib
-  = attribute ttp:pixelAspectRatio { TTAF.PixelAspectRatio.datatype }?
-TTAF.subFrameRate.attrib
-  = attribute ttp:subFrameRate { TTAF.SubFrameRate.datatype }?
-TTAF.tickRate.attrib
-  = attribute ttp:tickRate { TTAF.TickRate.datatype }?
-TTAF.timeBase.attrib
-  = attribute ttp:timeBase { TTAF.TimeBase.datatype }?
-
-# Parameter Attribute Class
-
-TTAF.Parameter.attrib.class &amp;=
-  TTAF.cellResolution.attrib,
-  TTAF.clockMode.attrib,
-  TTAF.dropMode.attrib,
-  TTAF.frameRate.attrib,
-  TTAF.frameRateMultiplier.attrib,
-  TTAF.markerMode.attrib,
-  TTAF.pixelAspectRatio.attrib,
-  TTAF.profile.attrib,
-  TTAF.subFrameRate.attrib,
-  TTAF.tickRate.attrib,
-  TTAF.timeBase.attrib
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-styling-attribs-module" id="rnc-dfxp-styling-attribs-module"/>B.1.2.15 Styling Attributes Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Styling Attributes Module ..............................
-# .......................................................................
-
-namespace tt = "http://www.w3.org/ns/ttml"
-namespace tts = "http://www.w3.org/ns/ttml#styling"
-namespace local = ""
-
-# Standard Style Attributes
-
-TTAF.backgroundColor.attrib
-  = attribute tts:backgroundColor { TTAF.Color.datatype }?
-TTAF.color.attrib
-  = attribute tts:color { TTAF.Color.datatype }?
-TTAF.direction.attrib
-  = attribute tts:direction { TTAF.Direction.datatype }?
-TTAF.display.attrib
-  = attribute tts:display { TTAF.Display.datatype }?
-TTAF.displayAlign.attrib
-  = attribute tts:displayAlign { TTAF.DisplayAlign.datatype }?
-TTAF.extent.attrib
-  = attribute tts:extent { TTAF.Extent.datatype }?
-TTAF.fontFamily.attrib
-  = attribute tts:fontFamily { TTAF.FontFamily.datatype }?
-TTAF.fontSize.attrib
-  = attribute tts:fontSize { TTAF.FontSize.datatype }?
-TTAF.fontStyle.attrib
-  = attribute tts:fontStyle { TTAF.FontStyle.datatype }?
-TTAF.fontWeight.attrib
-  = attribute tts:fontWeight { TTAF.FontWeight.datatype }?
-TTAF.lineHeight.attrib
-  = attribute tts:lineHeight { TTAF.LineHeight.datatype }?
-TTAF.opacity.attrib
-  = attribute tts:opacity { TTAF.Opacity.datatype }?
-TTAF.origin.attrib
-  = attribute tts:origin { TTAF.Origin.datatype }?
-TTAF.overflow.attrib
-  = attribute tts:overflow { TTAF.Overflow.datatype }?
-TTAF.padding.attrib
-  = attribute tts:padding { TTAF.Padding.datatype }?
-TTAF.showBackground.attrib
-  = attribute tts:showBackground { TTAF.ShowBackground.datatype }?
-TTAF.textAlign.attrib
-  = attribute tts:textAlign { TTAF.TextAlign.datatype }?
-TTAF.textDecoration.attrib
-  = attribute tts:textDecoration { TTAF.TextDecoration.datatype }?
-TTAF.textOutline.attrib
-  = attribute tts:textOutline { TTAF.TextOutline.datatype }?
-TTAF.unicodeBidi.attrib
-  = attribute tts:unicodeBidi { TTAF.UnicodeBidi.datatype }?
-TTAF.visibility.attrib
-  = attribute tts:visibility { TTAF.Visibility.datatype }?
-TTAF.wrapOption.attrib
-  = attribute tts:wrapOption { TTAF.WrapOption.datatype }?
-TTAF.writingMode.attrib
-  = attribute tts:writingMode { TTAF.WritingMode.datatype }?
-TTAF.zIndex.attrib
-  = attribute tts:zIndex { TTAF.ZIndex.datatype }?
-
-# Extension Style Attributes
-
-TTAF.Styling.ForeignExtension.attrib =
-  attribute * - ( tt:* | tts:* | xml:* | local:* ) { text }
-
-# Styling Attribute Class
-
-TTAF.Styling.attrib.class &amp;=
-  TTAF.backgroundColor.attrib,
-  TTAF.color.attrib,
-  TTAF.direction.attrib,
-  TTAF.display.attrib,
-  TTAF.displayAlign.attrib,
-  TTAF.extent.attrib,
-  TTAF.fontFamily.attrib,
-  TTAF.fontSize.attrib,
-  TTAF.fontStyle.attrib,
-  TTAF.fontWeight.attrib,
-  TTAF.lineHeight.attrib,
-  TTAF.opacity.attrib,
-  TTAF.origin.attrib,
-  TTAF.overflow.attrib,
-  TTAF.padding.attrib,
-  TTAF.showBackground.attrib,
-  TTAF.textAlign.attrib,
-  TTAF.textDecoration.attrib,
-  TTAF.textOutline.attrib,
-  TTAF.unicodeBidi.attrib,
-  TTAF.visibility.attrib,
-  TTAF.wrapOption.attrib,
-  TTAF.writingMode.attrib,
-  TTAF.zIndex.attrib
-
-# Style Binding Attribute Class
-
-TTAF.StyleBinding.attrib.class &amp;=
-  TTAF.style.attrib
-
-# Styled Content Attribute Class
-
-TTAF.Styled.extra.attrib = empty
-TTAF.Styled.attrib.class &amp;=
-  TTAF.Styling.attrib.class,
-  TTAF.StyleBinding.attrib.class,
-  TTAF.Styled.extra.attrib
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-styling-module" id="rnc-dfxp-styling-module"/>B.1.2.16 Styling Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Styling Module .........................................
-# .......................................................................
-
-# style reference attribute; must reference /tt/head/styling/style
-TTAF.style.attrib
-  = attribute style { xsd:IDREFS }?
-
-# styling - generic styling container
-TTAF.styling =
-  element styling {
-    TTAF.styling.attlist,
-    TTAF.styling.content
-  }
-
-TTAF.styling.attlist &amp;=
-  TTAF.Core.attrib.class
-
-TTAF.styling.content.extra = empty
-TTAF.styling.content =
-  (TTAF.Metadata.class*,
-   TTAF.styling.defs.class*,
-   TTAF.styling.content.extra*)
-
-# style - style declaration
-TTAF.styling.style =
-  element style {
-    TTAF.styling.style.attlist,
-    TTAF.styling.style.content
-  }
-
-TTAF.styling.style.attlist =
-  TTAF.Core.attrib.class,
-  TTAF.style.attrib,
-  (TTAF.Styling.attrib.class |
-   TTAF.Styling.ForeignExtension.attrib+ )
-
-TTAF.styling.style.content.extra = empty
-TTAF.styling.style.content =
-  (TTAF.styling.style.content.extra)*
-
-# style definitions class
-TTAF.styling.defs.extra = empty
-TTAF.styling.defs.class = 
-  TTAF.styling.style
-  | TTAF.styling.defs.extra
-
-# .......................................................................
-# .......................................................................
-# .......................................................................</pre></div></div><div class="div4">
-<h5><a name="rnc-dfxp-timing-attribs-module" id="rnc-dfxp-timing-attribs-module"/>B.1.2.17 Timing Attributes Module</h5><div class="exampleInner"><pre># .......................................................................
-# TT-AF 1.0 DFXP Timing Attributes Module ...............................
-# .......................................................................
-
-# Timing Attributes
-
-TTAF.timing.begin.attrib
-  = attribute begin { TTAF.TimeCoordinate.datatype }?
-TTAF.timing.dur.attrib
-  = attribute dur { TTAF.TimeDuration.datatype }?
-TTAF.timing.end.attrib
-  = attribute end { TTAF.TimeCoordinate.datatype }?
-TTAF.timing.timeContainer.attrib
-  = attribute timeContainer { TTAF.TimeContainer.datatype }?
-
-# Timing Interval Attribute class
-
-TTAF.TimingInterval.extra.attrib = empty
-TTAF.TimingInterval.attrib.class &amp;=
-  TTAF.timing.begin.attrib,
-  TTAF.timing.dur.attrib,
-  TTAF.timing.end.attrib,
-  TTAF.TimingInterval.extra.attrib
-
-# Timing Container Attribute class
-
-TTAF.TimingContainer.extra.attrib = empty
-TTAF.TimingContainer.attrib.class &amp;=
-  TTAF.timing.timeContainer.attrib,
-  TTAF.TimingContainer.extra.attrib
-
-# Timed Content Attribute Class
-
-TTAF.Timed.extra.attrib = empty
-TTAF.Timed.attrib.class &amp;=
-  TTAF.TimingInterval.attrib.class,
-  TTAF.Timed.extra.attrib
-
-# Timed Content Container Attribute Class
-
-TTAF.TimedContainer.extra.attrib = empty
-TTAF.TimedContainer.attrib.class &amp;=
-  TTAF.Timed.attrib.class,
-  TTAF.TimingContainer.attrib.class,
-  TTAF.TimedContainer.extra.attrib
-
-# .......................................................................
-# .......................................................................
-# .......................................................................
-</pre></div></div></div></div><div class="div2">
-<h3><a name="dfxp-schema-xsd" id="dfxp-schema-xsd"/>B.2 XML Schema Definition (XSD) Schema</h3><p>This section specifies a W3C XML Schema Definition (XSD) <a href="#xsd-1">[XML Schema Part 1]</a> based schema
-for DFXP Content, also available in a <a href="xsd/schema.zip">ZIP
-Archive</a>.</p><div class="div3">
-<h4><a name="xsd-dfxp-driver-schema" id="xsd-dfxp-driver-schema"/>B.2.1 Driver</h4><div class="exampleInner"><pre>&lt;xs:schema targetNamespace="http://www.w3.org/ns/ttml" xml:lang="en"
-  xmlns:xs="http://www.w3.org/2001/XMLSchema"
-  xmlns:tt="http://www.w3.org/ns/ttml"&gt;
-  &lt;xs:include schemaLocation="ttaf1-dfxp-document.xsd"/&gt;
-&lt;/xs:schema&gt;
-</pre></div></div><div class="div3">
-<h4><a name="xsd-dfxp-modules" id="xsd-dfxp-modules"/>B.2.2 Modules</h4><div class="div4">
-<h5><a name="xsd-dfxp-animation-module" id="xsd-dfxp-animation-module"/>B.2.2.1 Animation Module</h5><div class="exampleInner"><pre>&lt;xs:schema targetNamespace="http://www.w3.org/ns/ttml" xml:lang="en"
-  xmlns:xs="http://www.w3.org/2001/XMLSchema"
-  xmlns:tt="http://www.w3.org/ns/ttml"
-  xmlns:ttm="http://www.w3.org/ns/ttml#metadata"
-  xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
-  &lt;xs:include schemaLocation="ttaf1-dfxp-core-attribs.xsd"/&gt;
-  &lt;xs:include schemaLocation="ttaf1-dfxp-timing-attribs.xsd"/&gt;
-  &lt;xs:include schemaLocation="ttaf1-dfxp-metadata.xsd"/&gt;
-  &lt;xs:import namespace="http://www.w3.org/ns/ttml#styling"
-    schemaLocation="ttaf1-dfxp-styling-attribs.xsd"/&gt;
-  &lt;xs:attributeGroup name="set.attlist"&gt;
-    &lt;xs:attributeGroup ref="tt:Core.attrib.class" /&gt;
-    &lt;xs:attributeGroup ref="tt:Timed.attrib.class" /&gt;
-    &lt;xs:attributeGroup ref="tts:Styling.attrib.class" /&gt;
-  &lt;/xs:attributeGroup&gt;
-  &lt;xs:complexType name="set.eltype"&gt;
-    &lt;xs:sequence&gt;
-      &lt;xs:group ref="tt:Metadata.class" minOccurs="0" maxOccurs="unbounded"/&gt;
-    &lt;/xs:sequence&gt;
-    &lt;xs:attributeGroup ref="tt:set.attlist"/&gt;
-  &lt;/xs:complexType&gt;
-  &lt;xs:element name="set" type="tt:set.eltype"/&gt;
-  &lt;xs:group name="Animation.class"&gt;
-    &lt;xs:choice&gt;
-      &lt;xs:element ref="tt:set"/&gt;
-    &lt;/xs:choice&gt;
-  &lt;/xs:group&gt;
-&lt;/xs:schema&gt;
-</pre></div></div><div class="div4">
-<h5><a name="xsd-dfxp-content-module" id="xsd-dfxp-content-module"/>B.2.2.2 Content Module</h5><div class="exampleInner"><pre>&lt;xs:schema targetNamespace="http://www.w3.org/ns/ttml" xml:lang="en"
-  xmlns:xs="http://www.w3.org/2001/XMLSchema"
-  xmlns:tt="http://www.w3.org/ns/ttml"
-  xmlns:ttm="http://www.w3.org/ns/ttml#metadata"
-  xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
-  &lt;xs:include schemaLocation="ttaf1-dfxp-core-attribs.xsd"/&gt;
-  &lt;xs:include schemaLocation="ttaf1-dfxp-timing-attribs.xsd"/&gt;
-  &lt;xs:include schemaLocation="ttaf1-dfxp-metadata.xsd"/&gt;
-  &lt;xs:include schemaLocation="ttaf1-dfxp-animation.xsd"/&gt;
-  &lt;xs:include schemaLocation="ttaf1-dfxp-layout.xsd"/&gt;
-  &lt;xs:include schemaLocation="ttaf1-dfxp-styling.xsd"/&gt;
-  &lt;xs:import namespace="http://www.w3.org/ns/ttml#metadata"
-    schemaLocation="ttaf1-dfxp-metadata-attribs.xsd"/&gt;
-  &lt;xs:attributeGroup name="body.attlist"&gt;
-    &lt;xs:attributeGroup ref="tt:Core.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:TimedContainer.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:RegionBinding.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:Styled.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="ttm:Metadata.attrib.class"/&gt;
-  &lt;/xs:attributeGroup&gt;
-  &lt;xs:attributeGroup name="div.attlist"&gt;
-    &lt;xs:attributeGroup ref="tt:Core.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:TimedContainer.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:RegionBinding.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:Styled.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="ttm:Metadata.attrib.class"/&gt;
-  &lt;/xs:attributeGroup&gt;
-  &lt;xs:attributeGroup name="p.attlist"&gt;
-    &lt;xs:attributeGroup ref="tt:Core.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:TimedContainer.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:RegionBinding.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:Styled.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="ttm:Metadata.attrib.class"/&gt;
-  &lt;/xs:attributeGroup&gt;
-  &lt;xs:attributeGroup name="span.attlist"&gt;
-    &lt;xs:attributeGroup ref="tt:Core.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:TimedContainer.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:RegionBinding.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:Styled.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="ttm:Metadata.attrib.class"/&gt;
-  &lt;/xs:attributeGroup&gt;
-  &lt;xs:attributeGroup name="br.attlist"&gt;
-    &lt;xs:attributeGroup ref="tt:Core.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="tt:Styled.attrib.class"/&gt;
-    &lt;xs:attributeGroup ref="ttm:Metadata.attrib.class"/&gt;
-  &lt;/xs:attributeGroup&gt;
-  &lt;xs:complexType name="body.eltype"&gt;
-    &lt;xs:sequence&gt;
-      &lt;xs:group ref="tt:Metadata.class" minOccurs="0" maxOccurs="unbounded"/&gt;
-      &lt;xs:group ref="tt:Animation.class" minOccurs="0" maxOccurs="unbounded"/&gt;
-      &lt;xs:element ref="tt:div" minOccurs="0" maxOccurs="unbounded"/&gt;
-    &lt;/xs:sequence&gt;
-    &lt;xs:attributeGroup ref="tt:body.attlist"/&gt;
-  &lt;/xs:complexType&gt;
-  &lt;xs:complexType name="div.eltype"&gt;
-    &lt;xs:sequence&gt;
-      &lt;xs:group ref="tt:Metadata.class" minOccurs="0" maxOccurs="unbounded"/&gt;
-      &lt;xs:group ref="tt:Animation.class" minOccurs="0" maxOccurs="unbounded"/&gt;
-      &lt;xs:group ref="tt:Block.class" minOccurs="0" maxOccurs="unbounded"/&gt;
-    &lt;/xs:sequence&gt;
-    &lt;xs:attributeGroup ref="tt:div.attlist"/&gt;
-  &lt;/xs:complexType&gt;
-  &lt;xs:complexType name="p.eltype" mixed="true"&gt;
-    &lt;xs:sequence&gt;
-      &lt;xs:group ref="tt:Metadata.class" minOccurs="0" maxOccurs="unbounded"/&gt;
-      &lt;xs:group ref="tt:Animation.class" minOccurs="0" maxOccurs="unbounded"/&gt;
-      &lt;xs:group ref="tt:Inline.class" minOccurs="0" maxOccurs="unbounded"/&gt;
-    &lt;/xs:sequence&gt;
-    &lt;xs:attributeGroup ref="tt:p.attlist"/&gt;
-  &lt;/xs:complexType&gt;
-  &lt;xs:complexType name="span.eltype" mixed="true