[imsc] merge with trunk
authorpal@sandflow.org
Tue, 23 Sep 2014 15:34:45 -0700
changeset 716 2879d372e119
parent 715 7084721154b6 (current diff)
parent 714 e5d31f0ff77a (diff)
child 717 7221f45db85f
[imsc] merge with trunk
--- a/ttml1/spec/ttml1-errata.html	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml1/spec/ttml1-errata.html	Tue Sep 23 15:34:45 2014 -0700
@@ -54,7 +54,7 @@
     <h2>Conventions</h2>
     <p>Added text marked <span class="diff-add">thus</span>. Removed text
       marked <span class="diff-del">thus</span>. Changed text marked <span class="diff-chg">thus</span>.</p>
-    <h2 id="errors">Known errata as of 31 July 2014</h2>
+    <h2 id="errors">Known errata as of 17 September 2014</h2>
     <ul>
       <li><a href="#errata-2.2-1">Correction in TTML1 Section 2.2 Terminology</a>
           (published 2014-07-31)</li>
@@ -62,8 +62,12 @@
           (published 2014-07-31)</li>
       <li><a href="#errata-5.2-1">Correction in TTML1 Section 5.2 Profiles</a>
           (published 2014-01-30)</li>
+      <li><a href="#errata-6.1.5-1">Correction in TTML1 Section 6.1.5 Profiles</a>
+          (published 2014-09-14)</li>
       <li><a href="#errata-8.2.7-1">Correction in TTML1 Section 8.2.7 tts:extent attribute</a>
           (published 2014-07-17)</li>
+      <li><a href="#errata-8.2.15-1">Correction in TTML1 Section 8.2.16 tts:overflow attribute</a>
+          (published 2014-09-17)</li>
       <li><a href="#errata-8.2.16-1">Correction in TTML1 Section 8.2.16 tts:padding attribute</a>
           (published 2014-07-17)</li>
       <li><a href="#errata-8.2.17-1">Correction in TTML1 Section 8.2.17 tts:showBackground attribute</a>
@@ -108,6 +112,14 @@
     <p>Change "... and must not <span class="diff-del">be </span>appear ..."</p>
     <p>to read "... and must not appear ...".</p>
     <hr />
+    <p id="errata-6.1.5-1">Correction
+        in <a href="http://www.w3.org/TR/2013/REC-ttml1-20130924/#parameter-vocabulary-extension">TTML1 Section 6.1.5 ttp:extension</a> (published 2014-09-14) </p>
+    <p class="description"><span class="title-description">Description</span>:</p>
+    Minor typographical error, in the second paragraph under XML Representation - Element Information Item ttp:extension.
+    <p class="description"><em><strong><span class="title-correction">Resolution</span></strong></em>:</p>
+    <p>Change "... of the <code>ttp:feature</code> element ..."</p>
+    <p>to read "... of the <span class="diff-chg"><code>ttp:extension</code></span> element ...".</p>
+    <hr />
     <p id="errata-8.2.7-1">Correction
         in <a href="http://www.w3.org/TR/2013/REC-ttml1-20130924/#style-attribute-extent">TTML1 Section 8.2.7 - tts:extent attribute</a> (published 2014-07-17) </p>
     <p class="description"><span class="title-description">Description</span>:</p>
@@ -118,6 +130,31 @@
     The rationale for this difference in treatment is that use of a larger extent ensures that the affected content will be contained in the region area without
     causing region overflow, while use of a smaller extent makes region overflow more likely.</span></p>
     <hr />
+    <p id="errata-8.2.15-1">Correction
+        in <a href="http://www.w3.org/TR/2013/REC-ttml1-20130924/#style-attribute-overflow">TTML1 Section 8.2.15 - tts:overflow attribute</a> (published 2014-09-17) </p>
+    <p class="description"><span class="title-description">Description</span>:</p>
+    Clarify context in which oveflow semantics apply and constraints on those semantics when they do apply.
+    <p class="description"><em><strong><span class="title-correction">Resolution</span></strong></em>:</p>
+    <p>Add the following <strong>Note</strong> immediately after the paragraph starting with "If the value of this attribute is <code>visible</code>...":</p>
+    <p><b class="diff-add">Note:</b></p>
+    <p><span class="diff-add">This attribute has no impact on presentation processing when no overflow condition applies. Furthermore, an overflow condition
+    only applies in either (or both) of two specific contexts: (1) when <code>tts:wrapOption</code> is <code>noWrap</code> and the bounding box of some descendant glyph area
+    overflows (extends outside of) the containing region's nominal content area extent in the inline progression dimension,
+    or (and) (2) when the bounding box of some descendant line area overflows
+    (extends outside of) the containing region's nominal content area extent in the block progression dimension,
+    where the nominal content area extent in the inline and block progression
+    dimensions is determined by the computed values of the <code>tts:extent</code> and <code>tts:padding</code> style properties of the containing region.
+    Furthermore, when an overflow condition applies, it is not intended that the effective extent of the region be modified for the purpose of presentation processing.
+    For example, the area painted with the region's background color is not extended in either dimension to enclose the overflowed content.</span></p>
+    <p><span class="diff-add">Note that,
+    in particular, the normative text in the previous paragraph "region composition and layout must be performed as if the region's width and height
+    were unconstrained" refers to the process of determining the effective extent and origin of
+    descendant line areas produced in either (or both) of the two overflow contexts described here, and
+    is not intended to imply that the region extent is altered for the purpose of determining the region's padding area insets or the extent of its background color.
+    More specifically, the normative language above is not intended to override or contradict the semantics of
+    <a href="http://www.w3.org/TR/2013/REC-ttml1-20130924/#xsl11">[XSL 1.1]</a>, &sect; 7.21.2, or of
+    <a href="http://www.w3.org/TR/2013/REC-ttml1-20130924/#css2">[CSS2]</a>, &sect; 11.1.1, on which the former is based.</span></p>
+    <hr />
     <p id="errata-8.2.16-1">Correction
         in <a href="http://www.w3.org/TR/2013/REC-ttml1-20130924/#style-attribute-padding">TTML1 Section 8.2.16 - tts:padding attribute</a> (published 2014-07-17) </p>
     <p class="description"><span class="title-description">Description</span>:</p>
--- a/ttml2/spec/acknowledgements.xml	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/acknowledgements.xml	Tue Sep 23 15:34:45 2014 -0700
@@ -10,7 +10,7 @@
 by members: Micheal Dolan (SMPTE time codes, streaming; SMPTE liaison), David
 Kirby (introductory example document; SMPTE time codes, descriptive metadata; EBU/AAF liaison), Geoff Freed (styling
 and example images of style properties), Sean Hayes (advanced profile
-concepts, including applicative timing), Eric Hodge (timing),
+concepts, including applicative timing), Erik Hodge (timing),
 Thierry Michel (metadata), and Dave Singer (animation, scrolling).</p>
 <p>The Working Group dedicates this specification to our colleague David Kirby.</p>
 </inform-div1>
Binary file ttml2/spec/images/ruby_1.png has changed
Binary file ttml2/spec/images/ruby_2.png has changed
Binary file ttml2/spec/rnc/schema.zip has changed
--- a/ttml2/spec/rnc/ttml2-datatypes.rnc	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/rnc/ttml2-datatypes.rnc	Tue Sep 23 15:34:45 2014 -0700
@@ -132,6 +132,13 @@
   "continuous" |
   "discontinuous"
 
+TTAF.MediaDuration.datatype =
+  TTAF.TimeDuration.datatype |
+  "indefinite"
+
+TTAF.MediaOffset.datatype =
+  string
+
 TTAF.MetadataAgentType.datatype =
   "person" |
   "character" |
@@ -215,6 +222,26 @@
   TTAF.MetadataRoleBaseType.datatype |
   xsd:NMTOKEN { pattern = "x-\c+" }
 
+TTAF.Ruby.datatype =
+  "none" |
+  "container" |
+  "base" |
+  "baseContainer" |
+  "text" |
+  "textContainer" |
+  "delimiter"
+
+TTAF.RubyAlign.datatype =
+  "start" |
+  "center" |
+  "spaceBetween" |
+  "spaceAround"
+
+TTAF.RubyPosition.datatype =
+  "before" |
+  "after" |
+  "interCharacter"
+
 TTAF.ShowBackground.datatype =
   "always" |
   "whenActive"
--- a/ttml2/spec/rnc/ttml2-document.rnc	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/rnc/ttml2-document.rnc	Tue Sep 23 15:34:45 2014 -0700
@@ -12,7 +12,7 @@
 TTAF.tt.attlist &=
   TTAF.Core.required.attrib.class,
   TTAF.Parameter.attrib.class,
-  TTAF.extent.attrib
+  TTAF.Styled.attrib.class
 
 TTAF.tt.content =
   (TTAF.head?, TTAF.body?)
--- a/ttml2/spec/rnc/ttml2-parameter-attribs.rnc	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/rnc/ttml2-parameter-attribs.rnc	Tue Sep 23 15:34:45 2014 -0700
@@ -26,6 +26,10 @@
   = attribute ttp:inferProcessorProfileSource { TTAF.InferProcessorProfileSource.datatype }?
 TTAF.markerMode.attrib
   = attribute ttp:markerMode { TTAF.MarkerMode.datatype }?
+TTAF.mediaDuration.attrib
+  = attribute ttp:mediaDuration { TTAF.MediaDuration.datatype }?
+TTAF.mediaOffset.attrib
+  = attribute ttp:mediaOffset { TTAF.MediaOffset.datatype }?
 TTAF.permitFeatureNarrowing.attrib
   = attribute ttp:permitFeatureNarrowing { TTAF.PermitFeatureNarrowingOrWidening.datatype }?
 TTAF.permitFeatureWidening.attrib
--- a/ttml2/spec/rnc/ttml2-styling-attribs.rnc	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/rnc/ttml2-styling-attribs.rnc	Tue Sep 23 15:34:45 2014 -0700
@@ -40,6 +40,12 @@
   = attribute tts:overflow { TTAF.Overflow.datatype }?
 TTAF.padding.attrib
   = attribute tts:padding { TTAF.Padding.datatype }?
+TTAF.ruby.attrib
+  = attribute tts:ruby { TTAF.Ruby.datatype }?
+TTAF.rubyAlign.attrib
+  = attribute tts:rubyAlign { TTAF.RubyAlign.datatype }?
+TTAF.rubyPosition.attrib
+  = attribute tts:rubyPosition { TTAF.RubyPosition.datatype }?
 TTAF.showBackground.attrib
   = attribute tts:showBackground { TTAF.ShowBackground.datatype }?
 TTAF.textAlign.attrib
@@ -85,6 +91,9 @@
   TTAF.origin.attrib,
   TTAF.overflow.attrib,
   TTAF.padding.attrib,
+  TTAF.ruby.attrib,
+  TTAF.rubyAlign.attrib,
+  TTAF.rubyPosition.attrib,
   TTAF.showBackground.attrib,
   TTAF.textAlign.attrib,
   TTAF.textDecoration.attrib,
--- a/ttml2/spec/rnc/ttml2-styling.rnc	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/rnc/ttml2-styling.rnc	Tue Sep 23 15:34:45 2014 -0700
@@ -19,6 +19,7 @@
 TTAF.styling.content.extra = empty
 TTAF.styling.content =
   (TTAF.Metadata.class*,
+   TTAF.styling.initial*,
    TTAF.styling.defs.class*,
    TTAF.styling.content.extra*)
 
@@ -40,6 +41,24 @@
   (TTAF.Metadata.class*,
    TTAF.styling.style.content.extra*)
 
+# initial - initial declaration
+TTAF.styling.initial =
+  element initial {
+    TTAF.styling.initial.attlist,
+    TTAF.styling.initial.content
+  }
+
+TTAF.styling.initial.attlist =
+  TTAF.Core.attrib.class,
+  TTAF.style.attrib,
+  (TTAF.Styling.attrib.class |
+   TTAF.Styling.ForeignExtension.attrib+ )
+
+TTAF.styling.initial.content.extra = empty
+TTAF.styling.initial.content =
+  (TTAF.Metadata.class*,
+   TTAF.styling.initial.content.extra*)
+
 # style definitions class
 TTAF.styling.defs.extra = empty
 TTAF.styling.defs.class = 
--- a/ttml2/spec/ttml2-changes.html	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/ttml2-changes.html	Tue Sep 23 15:34:45 2014 -0700
@@ -33,6 +33,8 @@
 <pre>
 <span class="strong">Technical Changes</span>
 
+* In 5.1, add TT Intermediate Synchronic Document Namespace to Table 5-1.
+
 * In 5.2, add TTML2 (transformation, presentation, full) profiles.
 
 * In 5.2, specify profile state concepts and algorithm semantics in detail.
@@ -42,15 +44,41 @@
   for a presentation processor, then use a presentation profile as a default
   not a transformation profile.
 
-* In 5.3.1, add new animation vocabulary, 'animation' and 'animate', to Table 5-3.
-
-* In 5.3.1, add new animation vocabulary, 'animate', to Animation.class in Table 5-4.
+* In 5.3.1, add new animation vocabulary, 'animation' and 'animate', to
+  Table 5-3.
 
-* In 5.3.1, add new attribute vocabulary, 'tts:border' and 'tts:textOrientation',
+* In 5.3.1, add new parameter attribute vocabulary
+'ttp:contentProfiles',
+'ttp:contentProfileCombination',
+'ttp:inferProcessorProfileMethod',
+'ttp:inferProcessorProfileSource',
+'ttp:mediaDuration,
+'ttp:mediaOffset',
+'ttp:permitFeatureNarrowing',
+'ttp:permitFeatureWidening',
+'ttp:processorProfiles',
+'ttp:processorProfileCombination',
+'ttp:validation',
+'ttp:validationAction',
+and
+'ttp:version'
+to Table 5-5.
+
+* In 5.3.1, add new animation vocabulary, 'animate', to Animation.class in
+  Table 5-4.
+
+* In 5.3.1, add new styling attribute vocabulary
+'tts:border',
+'tts:ruby',
+'tts:rubyAlign',
+'tts:rubyPosition',
+and
+'tts:textOrientation'
+to Table 5-5.
+
+* In 5.3.1, add new animation binding attribute vocabulary, 'animate',
   to Table 5-5.
 
-* In 5.3.1, add new attribute vocabulary, 'animate', to Table 5-5.
-
 * In 6.1.1, add support for nesting profiles by changing content model of
   ttp:profile to permit either (1) a list of features/extensions or (2)
   a list of nested profiles.
@@ -95,6 +123,10 @@
 
 * In 6.2, add 'ttp:inferProcessorProfileSource' parameter attribute.
 
+* In 6.2, add 'ttp:mediaDuration' parameter attribute.
+
+* In 6.2, add 'ttp:mediaOffset' parameter attribute.
+
 * In 6.2, add 'ttp:permitFeatureNarrowing' parameter attribute.
 
 * In 6.2, add 'ttp:permitFeatureWidening' parameter attribute.
@@ -103,6 +135,10 @@
 
 * In 6.2, add 'ttp:processorProfileCombination' parameter attribute.
 
+* In 6.2, add 'ttp:validation parameter attribute.
+
+* In 6.2, add 'ttp:validationAction parameter attribute.
+
 * In 6.2, add 'ttp:version' parameter attribute.
 
 * In 6.2.7, deprecate 'ttp:markerMode' parameter attribute, requiring it be
@@ -113,6 +149,10 @@
 * In 6.2.10, deprecate 'ttp:profile' parameter attribute, replacing it with
   'ttp:processorProfiles' parameter attribute.
 
+* In 7.1.1, add {any attribute in TT Style Namespace} to definition of 'tt'
+  element in order to support a common ancestor of 'region' elements from
+  which styles may be inherited.
+
 * In 7.1.2, add new 'animation' container element as optional child of 'head'
   element.
 
@@ -142,12 +182,24 @@
 
 * In 7.1.7, add 'animate' attribute to 'br' element.
 
-* In 8.1.2, add Metadata.class children to 'style' element.
+* Insert new subsection 8.1.2, defining  'initial' element type used to
+  redefine initial value of style property(ies).
+
+* In 8.1.3, add Metadata.class children to 'style' element.
 
 * In 8.2, add 'tts:border' styling attribute.
 
+* In 8.2, add 'tts:ruby styling attribute.
+
+* In 8.2, add 'tts:rubyAlign styling attribute.
+
+* In 8.2, add 'tts:rubyPosition styling attribute.
+
 * In 8.2, add 'tts:textOrientation' styling attribute.
 
+* In 8.2 prologue, add proscription against specifying non-applicable,,
+  non-inheritable style attributes on stylable elements.
+
 * In 8.2.1, add 'set' element to enumeration of element types to which 'style'
   attribute applies.
 
@@ -184,12 +236,18 @@
 * In 8.3, add &lt;border-color&gt;, &lt;border-style&gt;, and &lt;border-width&gt;
   value expressions.
 
+* Add section 8.4.2.3 defining root style inheritance.
+
 * In 8.3.12, add 'vw', 'vh', 'vmin', and 'vmax' units of measure in order to
   express lengths as a percentage of the root container region (as viewport).
 
 * In 8.4.4, add semantics for determining specified style set and computed
   style set for 'set' element.
 
+* In 8.4.4.2, rework SSS(E) processing algorithm to properly account for
+  inheritable and non-inheritable properties, use of specified initial
+  value overrides, and root style inheritance.
+
 * In 9.1.2, require out-of-line region to specify 'xml:id' attribute.
 
 * In 9.3.1, qualify default region in terms of out-of-line region(s).
@@ -218,9 +276,12 @@
 * In 11.3 (new), add new sub-section defining animation specific value
   expressions.
 
-* In Appendix C, remove contents for mediate type registration, since
-  registration has (will have) already occurred (by the time TTML2 goes to
-  FPWD).
+* In Appendix B, update referenced schemas to reflect new/changed vocabulary
+  definitions.
+
+* In Appendix C, replace former content specifying media type registration
+  (no longer needed since registration already occurred in TTML1 context)
+  with new (unrelated) material defining TTML ISD and ISD Sequence Formats.
 
 * In Appendix D, add #border, #textOrientation, and #version feature
   designators.
@@ -230,6 +291,15 @@
 * In Appendix F, add #border, #textOrientation, and #version feature
   designators in standard profiles.
 
+* In Appendix G, add (normative) reference to RFC2396 (URI).
+
+* In Appendix G, add (normative) reference to Ruby Annotations REC.
+
+* In Appendix G, add (normative) reference to CSS Ruby Draft.
+
+* In Appendix G, move SVG1.1 reference from Appendix H and update to Second
+  Edition.
+
 * In Appendix O, change appendix designation to normative, effectively
   changing the informative concrete encoding recommendation to a normative
   recommendation.
@@ -244,11 +314,17 @@
 
 <span class="strong">Editorial Changes</span>
 
+* In 2.1, add acronym: "ISD".
+
 * In 2.2, add definitions: "anonymous profile", "baseline profile",
   "content profile", "default processor profile", "designated profile",
   "enclosing document instance", "extension specification",
   "feature specification", "fragment identifier", "implied inline region",
-  "inline animation", "inline region", "nested profile", "nesting profile",
+  "inline animation", "inline region",
+  "intermediate synchronic document",
+  "intermediate synchronic document sequence",
+  "intermediate synchronic document sequence syntax",
+  "nested profile", "nesting profile",
   "non-nesting profile", "out-of-line animation", "out-of-line region",
   "profile", "profile designator", "profile fragment identifier",
   "profile specification", "top-level profile", "undesignated profile".
@@ -264,6 +340,9 @@
 
 * In 5.*, renumber tables to use M-N format.
 
+* In 5.1, extend note under Table 5-1 to clarify meaning of unqualified
+  attribute names.
+
 * In 6.*, renumber tables to use M-N format.
 
 * In 6.1.3, segregate the semantics of the 'value' attribute according to
@@ -274,19 +353,26 @@
 
 * In 8.2, add note about the use of non-applicable style attributes.
 
+* In 8.4.4.4, rework [filter] step to explicitly enumerate element types
+  not filtered.
+
 * In 9.2.1, add 'br' element to list of elements on which region attribute may
   be specified.
 
 * In 9.3, insert "Inline Regions" as sub-section 9.3.2, renumbering following
   sub-sections.
 
-* In Appendix G, add (normative) reference to RFC2396 (URI).
-
-* In Appendix G, move SVG1.1 reference from Appendix H and update to Second
-  Edition.
+* In 10.3, permit metric component to be omitted from offset-time, in which case
+  's' (seconds) is implied.
 
 * In Appendix H, add (non-normative) reference to CSS Writing Modes Level 3.
 
+* In Appendix H, add (non-normative) reference to Japanese Language Requirements
+  (JLREQ).
+
+* In Appendix H, add (non-normative) reference to original Namespaces in XML
+  REC (NSOriginal).
+
 * In Appendix H, add (non-normative) reference to SDP US.
 
 * In Appendix H, add (non-normative) reference to TTML1.
--- a/ttml2/spec/ttml2.html	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/ttml2.html	Tue Sep 23 15:34:45 2014 -0700
@@ -82,13 +82,13 @@
 .obsoleted { background-color: #f26d7d }
 .reqattr { font-weight: bold }
 .optattr { font-style: italic }
-</style><link rel="stylesheet" type="text/css" href="https://www.w3.org/StyleSheets/TR/W3C-ED.css"></head><body>Last Modified: $Date: 2014/08/07 16:46:04 $<div id="revisions"></div><div class="head">
+</style><link rel="stylesheet" type="text/css" href="https://www.w3.org/StyleSheets/TR/W3C-ED.css"></head><body>Last Modified: $Date: 2014/09/23 18:57:41 $<div id="revisions"></div><div class="head">
 <h1><a id="title"></a>Timed Text Markup Language 2 (TTML2)</h1>
-<h2><a id="w3c-doctype"></a>Editors' copy $Date: 2014/08/07 16:46:04 $ @@ @@@@ @@@@</h2><dl><dt>This version:</dt><dd>
+<h2><a id="w3c-doctype"></a>Editors' copy $Date: 2014/09/23 18:57:41 $ @@ @@@@ @@@@</h2><dl><dt>This version:</dt><dd>
 <a href="ttml2.html">ttml2.html</a>
 </dd><dt>Latest version:</dt><dd><a href="https://dvcs.w3.org/hg/ttml/raw-file/default/ttml2/spec/ttml2.html?content-type=text/html;charset=utf-8">https://dvcs.w3.org/hg/ttml/raw-file/default/ttml2/spec/ttml2.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>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
+</dd><dt>Editor:</dt><dd>Glenn Adams, Cox Communications, Inc.</dd><dt>Contributing Authors:</dt><dd>Mike Dolan, Invited Expert</dd><dd>Sean Hayes, Microsoft</dd><dd>Frans de Jong, European Broadcasting Union</dd><dd>Pierre-Anthony Lemieux, MovieLabs</dd><dd>Nigel Megitt, British Broadcasting Corporation</dd><dd>Dave Singer, Apple Computer</dd><dd>Jerry Smith, Microsoft</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=ttml2"><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), Version 2, also known as TTML2,
 in terms of a vocabulary and semantics thereof.</p><p>The Timed Text Markup Language is a content type that represents
@@ -152,18 +152,20 @@
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.8 <a href="#parameter-attribute-inferProcessorProfileMethod">ttp:inferProcessorProfileMethod</a><br>
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.9 <a href="#parameter-attribute-inferProcessorProfileSource">ttp:inferProcessorProfileSource</a><br>
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.10 <a href="#parameter-attribute-markerMode">ttp:markerMode</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.11 <a href="#parameter-attribute-permitFeatureNarrowing">ttp:permitFeatureNarrowing</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.12 <a href="#parameter-attribute-permitFeatureWidening">ttp:permitFeatureWidening</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.13 <a href="#parameter-attribute-pixelAspectRatio">ttp:pixelAspectRatio</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.14 <a href="#parameter-attribute-profile">ttp:profile</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.15 <a href="#parameter-attribute-processorProfiles">ttp:processorProfiles</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.16 <a href="#parameter-attribute-processorProfileCombination">ttp:processorProfileCombination</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.17 <a href="#parameter-attribute-subFrameRate">ttp:subFrameRate</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.18 <a href="#parameter-attribute-tickRate">ttp:tickRate</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.19 <a href="#parameter-attribute-timeBase">ttp:timeBase</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.20 <a href="#parameter-attribute-validation">ttp:validation</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.21 <a href="#parameter-attribute-validationAction">ttp:validationAction</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.22 <a href="#parameter-attribute-version">ttp:version</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.11 <a href="#parameter-attribute-mediaDuration">ttp:mediaDuration</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.12 <a href="#parameter-attribute-mediaOffset">ttp:mediaOffset</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.13 <a href="#parameter-attribute-permitFeatureNarrowing">ttp:permitFeatureNarrowing</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.14 <a href="#parameter-attribute-permitFeatureWidening">ttp:permitFeatureWidening</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.15 <a href="#parameter-attribute-pixelAspectRatio">ttp:pixelAspectRatio</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.16 <a href="#parameter-attribute-profile">ttp:profile</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.17 <a href="#parameter-attribute-processorProfiles">ttp:processorProfiles</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.18 <a href="#parameter-attribute-processorProfileCombination">ttp:processorProfileCombination</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.19 <a href="#parameter-attribute-subFrameRate">ttp:subFrameRate</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.20 <a href="#parameter-attribute-tickRate">ttp:tickRate</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.21 <a href="#parameter-attribute-timeBase">ttp:timeBase</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.22 <a href="#parameter-attribute-validation">ttp:validation</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.23 <a href="#parameter-attribute-validationAction">ttp:validationAction</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6.2.24 <a href="#parameter-attribute-version">ttp:version</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>
@@ -180,7 +182,8 @@
 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;&nbsp;&nbsp;&nbsp;&nbsp;8.1.2 <a href="#styling-vocabulary-initial">initial</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.1.3 <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>
@@ -199,16 +202,19 @@
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.15 <a href="#style-attribute-origin">tts:origin</a><br>
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.16 <a href="#style-attribute-overflow">tts:overflow</a><br>
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.17 <a href="#style-attribute-padding">tts:padding</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.18 <a href="#style-attribute-showBackground">tts:showBackground</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.19 <a href="#style-attribute-textAlign">tts:textAlign</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.20 <a href="#style-attribute-textDecoration">tts:textDecoration</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.21 <a href="#style-attribute-textOrientation">tts:textOrientation</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.22 <a href="#style-attribute-textOutline">tts:textOutline</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.23 <a href="#style-attribute-unicodeBidi">tts:unicodeBidi</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.24 <a href="#style-attribute-visibility">tts:visibility</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.25 <a href="#style-attribute-wrapOption">tts:wrapOption</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.26 <a href="#style-attribute-writingMode">tts:writingMode</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.27 <a href="#style-attribute-zIndex">tts:zIndex</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.18 <a href="#style-attribute-ruby">tts:ruby</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.19 <a href="#style-attribute-rubyAlign">tts:rubyAlign</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.20 <a href="#style-attribute-rubyPosition">tts:rubyPosition</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.21 <a href="#style-attribute-showBackground">tts:showBackground</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.22 <a href="#style-attribute-textAlign">tts:textAlign</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.23 <a href="#style-attribute-textDecoration">tts:textDecoration</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.24 <a href="#style-attribute-textOrientation">tts:textOrientation</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.25 <a href="#style-attribute-textOutline">tts:textOutline</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.26 <a href="#style-attribute-unicodeBidi">tts:unicodeBidi</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.27 <a href="#style-attribute-visibility">tts:visibility</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.28 <a href="#style-attribute-wrapOption">tts:wrapOption</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.29 <a href="#style-attribute-writingMode">tts:writingMode</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.2.30 <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-border-color">&lt;border-color&gt;</a><br>
@@ -234,6 +240,7 @@
 &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;&nbsp;&nbsp;&nbsp;&nbsp;8.4.2.3 <a href="#semantics-style-inheritance-root">Root 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>
@@ -302,7 +309,15 @@
 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> (Non-Normative)<br>
+C <a href="#isd">Intermediate Synchronic Document Syntax</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;C.1 <a href="#isd-vocabulary">ISD Vocabulary</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;C.1.1 <a href="#isd-vocabulary-sequence">isd:sequence</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;C.1.2 <a href="#isd-vocabulary-isd">isd:isd</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;C.1.3 <a href="#isd-vocabulary-css">isd:css</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;C.1.4 <a href="#isd-vocabulary-region">isd:region</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;C.2 <a href="#isd-parameter-attribute-set">ISD Parameter Attribute Set</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;C.3 <a href="#isd-interchange">ISD Interchange</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;C.4 <a href="#isd-examples">ISD Examples</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>
@@ -433,11 +448,11 @@
 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="#d3e25233">Element Derivation</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;J.2 <a href="#d3e25750">Attribute Derivation</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;J.1 <a href="#d3e27291">Element Derivation</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;J.2 <a href="#d3e27808">Attribute Derivation</a><br>
 K <a href="#qa">QA Framework Compliance</a> (Non-Normative)<br>
-&nbsp;&nbsp;&nbsp;&nbsp;K.1 <a href="#d3e26743">Requirements</a><br>
-&nbsp;&nbsp;&nbsp;&nbsp;K.2 <a href="#d3e26907">Guidelines</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;K.1 <a href="#d3e28801">Requirements</a><br>
+&nbsp;&nbsp;&nbsp;&nbsp;K.2 <a href="#d3e28965">Guidelines</a><br>
 L <a href="#streaming">Streaming TTML Content</a> (Non-Normative)<br>
 M <a href="#concrete-encoding">Concrete Encoding</a><br>
 N <a href="#time-expression-semantics">Time Expression Semantics</a><br>
@@ -647,7 +662,7 @@
 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 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="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>ISD</b></td><td class="def"><p>Intermedia Synchronic Document</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"><a id="terms-abstract-document-instance"></a>[abstract document instance]</dt><dd><p>An instance of an abstract data set as represented by a
 <a href="#terms-reduced-xml-infoset">reduced xml infoset</a>.</p></dd><dt class="label"><a id="terms-abstract-document-type"></a>[abstract document type]</dt><dd><p>A set of constraints that defines a class of <em>XML Information
 Sets</em> <a href="#infoset">[XML InfoSet]</a>.</p></dd><dt class="label"><a id="terms-anonymous-profile"></a>[anonymous profile]</dt><dd><p>See <a href="#terms-undesignated-profile">undesignated profile</a>.</p></dd><dt class="label"><a id="terms-attribute-information-item"></a>[attribute information item]</dt><dd><p>Each specified or defaulted attribute  of an XML document corresponds with an attribute information
@@ -707,7 +722,9 @@
 or <a href="#style-attribute-origin">tts:origin</a> style attribute on a <a href="#terms-content-element">content element</a>.
 There is a one-to-one relation between an inline <a href="#layout-vocabulary-region"><code>region</code></a> element and its
 parent <a href="#terms-content-element">content element</a>. An inline region is assigned its parent element's time interval as its active
-time interval. No <code>region</code> attribute makes reference to an inline region.</p></dd><dt class="label"><a id="terms-nested-profile"></a>[nested profile]</dt><dd><p>A constituent <a href="#terms-profile">profile</a> of a <a href="#terms-nesting-profile">nesting profile</a>, i.e., one of the
+time interval. No <code>region</code> attribute makes reference to an inline region.</p></dd><dt class="label"><a id="terms-intermediate-synchronic-document"></a>[intermediate synchronic document]</dt><dd><p>An abstract or concrete representation of the static content, styling, and layout of a source TTML <a href="#terms-document-instance">document instance</a>
+during a non-overlapping temporal interval that intersects with the source document's <a href="#terms-root-temporal-extent">root temporal extent</a>.</p></dd><dt class="label"><a id="terms-intermediate-synchronic-document-sequence"></a>[intermediate synchronic document sequence]</dt><dd><p>An abstract or concrete representation of a sequence of <a href="#terms-intermediate-synchronic-document">intermediate synchronic document</a> instances
+that effectively represent the content, styling, layout, and timing of a source TTML <a href="#terms-document-instance">document instance</a>.</p></dd><dt class="label"><a id="terms-intermediate-synchronic-document-sequence-syntax"></a>[intermediate synchronic document sequence syntax]</dt><dd><p>A formalism for use in the concrete representation of an <a href="#terms-intermediate-synchronic-document-sequence">intermediate synchronic document sequence</a>.</p></dd><dt class="label"><a id="terms-nested-profile"></a>[nested profile]</dt><dd><p>A constituent <a href="#terms-profile">profile</a> of a <a href="#terms-nesting-profile">nesting profile</a>, i.e., one of the
 descendant <code>ttp:profile</code> element(s) of a higher level (ancestor) <code>ttp:profile</code> element. A given <code>ttp:profile</code> may serve
 as both a <a href="#terms-nested-profile">nested profile</a> and a <a href="#terms-nesting-profile">nesting profile</a>.</p></dd><dt class="label"><a id="terms-nesting-profile"></a>[nesting profile]</dt><dd><p>A <a href="#terms-profile">profile</a> defined by making reference to one or more child <code>ttp:profile</code> element(s), wherein a
 profile combination method determines how profile specifications from the multiple child <code>ttp:profile</code> element(s) are combined.</p></dd><dt class="label"><a id="terms-non-nesting-profile"></a>[non-nesting profile]</dt><dd><p>A <a href="#terms-profile">profile</a> defined without making reference to one or more child <code>ttp:profile</code> element(s); that is,
@@ -899,7 +916,7 @@
 a <code>ttp:profile</code> attribute on its root
 <code>tt</code>
 element
-as defined by <a href="#parameter-attribute-profile"><b>6.2.14 ttp:profile</b></a>
+as defined by <a href="#parameter-attribute-profile"><b>6.2.16 ttp:profile</b></a>
 or (2)
 a <code>ttp:profile</code> element as a child of the
 <code>head</code> element as defined by
@@ -957,8 +974,12 @@
 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 <a href="#terms-document-instance">document instance</a>, it is not required that the default
 prefixes shown below are used. Any prefix or namespace binding that satisfies the constraints
-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 5-1 – 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
+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 5-1 – 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 Intermediate Synchronic Document</td><td><code>isd:</code></td><td><code>http://www.w3.org/ns/ttml#isd</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>If a reference to an attribute is used in this specification and the name
+of the attribute is not namespace qualified, then the attribute is implicitly qualified by
+the element type with which it is used. That is, the attribute resides in the so-called
+<a href="http://www.w3.org/TR/1999/REC-xml-names-19990114/#ns-breakdown"><em>per-element-type namespace partition</em></a>
+<a href="#nsoriginal">[NSOriginal]</a>, the members of which are interpreted in accordance with the definition of the element type on which they appear.</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
 future version of this specification). In such cases, the use of the
@@ -1231,19 +1252,20 @@
 Styling
 </td><td>
 <a href="#styling-vocabulary-styling">styling</a>,
+<a href="#styling-vocabulary-initial">initial</a>,
 <a href="#styling-vocabulary-style">style</a>
 </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 5-4 – Element Vocabulary Groups</b></a>.</p><a id="element-vocab-group-table"></a><table class="common"><caption>Table 5-4 – Element Vocabulary Groups</caption><col width="25%" span="1"><col span="1"><tbody><tr><th>Group</th><th>Elements</th></tr><tr><td>
+for TTML element types are enumerated in <a href="#element-vocab-group-table"><b>Table 5-4 – Element Vocabulary Groups</b></a>.</p><a id="element-vocab-group-table"></a><table class="common"><caption>Table 5-4 – Element Vocabulary Groups</caption><col width="25%" span="1"><col span="1"><tbody><tr><th>Group</th><th>Elements</th></tr><tr id="element-vocab-group-animation"><td>
 Animation.class
 </td><td>
 <a href="#animation-vocabulary-animate">animate</a> |
 <a href="#animation-vocabulary-set">set</a>
-</td></tr><tr><td>
+</td></tr><tr id="element-vocab-group-block"><td>
 Block.class
 </td><td>
 <a href="#content-vocabulary-div">div</a> |
 <a href="#content-vocabulary-p">p</a>
-</td></tr><tr><td>
+</td></tr><tr id="element-vocab-group-inline"><td>
 Inline.class
 </td><td>
 <a href="#content-vocabulary-span">span</a> |
@@ -1251,9 +1273,9 @@
 <code>#PCDATA</code>
 </td></tr><tr><td>
 Layout.class
-</td><td>
+</td><td id="element-vocab-group-layout">
 <a href="#layout-vocabulary-region">region</a>
-</td></tr><tr><td>
+</td></tr><tr id="element-vocab-group-metadata"><td>
 Metadata.class
 </td><td>
 <a href="#metadata-vocabulary-metadata">metadata</a> |
@@ -1261,28 +1283,28 @@
 <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><p>The attribute vocabulary specified for use with the core vocabulary
+</td></tr><tr id="element-vocab-group-parameters"><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 5-5 – Attribute Vocabulary</b></a>.</p><a id="attribute-vocab-table"></a><table class="common"><caption>Table 5-5 – Attribute Vocabulary</caption><col width="25%" span="1"><col span="1"><tbody><tr><th>Module</th><th>Attributes</th></tr><tr><td>
+<a href="#attribute-vocab-table"><b>Table 5-5 – Attribute Vocabulary</b></a>.</p><a id="attribute-vocab-table"></a><table class="common"><caption>Table 5-5 – Attribute Vocabulary</caption><col width="25%" span="1"><col span="1"><tbody><tr><th>Module</th><th>Attributes</th></tr><tr id="attribute-vocab-group-animation-binding"><td>
 Animation Binding Attribute
 </td><td>
 <a href="#animation-attribute-animate">animate</a>
-</td></tr><tr><td>
+</td></tr><tr id="attribute-vocab-group-core"><td>
 Core Attributes
 </td><td>
 <a href="#content-attribute-id">xml:id</a>,
 <a href="#content-attribute-lang">xml:lang</a>,
 <a href="#content-attribute-space">xml:space</a>
-</td></tr><tr><td>
+</td></tr><tr id="attribute-vocab-group-layout-binding"><td>
 Layout Binding Attribute
 </td><td>
 <a href="#layout-attribute-region">region</a>
-</td></tr><tr><td>
+</td></tr><tr id="attribute-vocab-group-metadata"><td>
 Metadata Attributes
 </td><td>
 <a href="#metadata-attribute-agent">ttm:agent</a>,
 <a href="#metadata-attribute-role">ttm:role</a>
-</td></tr><tr><td>
+</td></tr><tr id="attribute-vocab-group-parameters"><td>
 Parameter Attributes
 </td><td>
 <a href="#parameter-attribute-cellResolution">ttp:cellResolution</a>,
@@ -1295,6 +1317,8 @@
 <a href="#parameter-attribute-inferProcessorProfileMethod">ttp:inferProcessorProfileMethod</a>,
 <a href="#parameter-attribute-inferProcessorProfileSource">ttp:inferProcessorProfileSource</a>,
 <a href="#parameter-attribute-markerMode">ttp:markerMode</a>,
+<a href="#parameter-attribute-mediaDuration">ttp:mediaDuration</a>,
+<a href="#parameter-attribute-mediaOffset">ttp:mediaOffset</a>,
 <a href="#parameter-attribute-permitFeatureNarrowing">ttp:permitFeatureNarrowing</a>,
 <a href="#parameter-attribute-permitFeatureWidening">ttp:permitFeatureWidening</a>,
 <a href="#parameter-attribute-pixelAspectRatio">ttp:pixelAspectRatio</a>,
@@ -1307,11 +1331,11 @@
 <a href="#parameter-attribute-validation">ttp:validation</a>,
 <a href="#parameter-attribute-validationAction">ttp:validationAction</a>,
 <a href="#parameter-attribute-version">ttp:version</a>
-</td></tr><tr><td>
+</td></tr><tr id="attribute-vocab-group-style-binding"><td>
 Style Binding Attribute
 </td><td>
 <a href="#style-attribute-style">style</a>
-</td></tr><tr><td>
+</td></tr><tr id="attribute-vocab-group-style"><td>
 Styling Attributes
 </td><td>
 <a href="#style-attribute-backgroundColor">tts:backgroundColor</a>,
@@ -1330,6 +1354,9 @@
 <a href="#style-attribute-origin">tts:origin</a>,
 <a href="#style-attribute-overflow">tts:overflow</a>,
 <a href="#style-attribute-padding">tts:padding</a>,
+<a href="#style-attribute-ruby">tts:ruby</a>,
+<a href="#style-attribute-rubyAlign">tts:rubyAlign</a>,
+<a href="#style-attribute-rubyPosition">tts:rubyPosition</a>,
 <a href="#style-attribute-showBackground">tts:showBackground</a>,
 <a href="#style-attribute-textAlign">tts:textAlign</a>,
 <a href="#style-attribute-textDecoration">tts:textDecoration</a>,
@@ -1340,7 +1367,7 @@
 <a href="#style-attribute-wrapOption">tts:wrapOption</a>,
 <a href="#style-attribute-writingMode">tts:writingMode</a>,
 <a href="#style-attribute-zIndex">tts:zIndex</a>
-</td></tr><tr><td>
+</td></tr><tr id="attribute-vocab-group-timing"><td>
 Timing Attributes
 </td><td>
 <a href="#timing-attribute-begin">begin</a>,
@@ -1543,7 +1570,10 @@
 feature referenced by the <code>extends</code> attribute.
 The <code>restricts</code> attribute may be used to indicate that the feature being defined
 is, from either (or both) a syntactic or (and) semantic perspective, a proper subset of the
-feature referenced by the <code>restricts</code> attribute.</p><p>If the URI expressed by (1) the content of the <code>ttp:feature</code>
+feature referenced by the <code>restricts</code> attribute.
+If an <code>extends</code> attribute is specified, then a <code>restricts</code> attribute must
+not be specified on a <code>ttp:feature</code> element; likewise, if a <code>restricts</code> attribute
+is specified, then an <code>extends</code> attribute must not be specified.</p><p>If the URI expressed by (1) the content of the <code>ttp:feature</code>
 element, (2) the <code>extends</code> attribute, or (3) the <code>restricts</code> attribute
 is a relative URI, then, when combined with the
 feature namespace value expressed by the
@@ -1677,8 +1707,11 @@
 is, from either (or both) a syntactic or (and) semantic perspective, a proper superset of the
 feature or extension referenced by the <code>extends</code> attribute.
 The <code>restricts</code> attribute may be used to indicate that the extension being defined
-is, from either (or both) a syntacitc or (and) semantic perspective, a proper subset of the
-feature or extension referenced by the <code>restricts</code> attribute.</p><p>If the URI expressed by (1) the content of the <code>ttp:extension</code>
+is, from either (or both) a syntactic or (and) semantic perspective, a proper subset of the
+feature or extension referenced by the <code>restricts</code> attribute.
+If an <code>extends</code> attribute is specified, then a <code>restricts</code> attribute must
+not be specified on a <code>ttp:extension</code> element; likewise, if a <code>restricts</code> attribute
+is specified, then an <code>extends</code> attribute must not be specified.</p><p>If the URI expressed by (1) the content of the <code>ttp:extension</code>
 element, (2) the <code>extends</code> attribute, or (3) the <code>restricts</code> attribute
 is a relative URI, then, when combined with the
 extension namespace value expressed by the
@@ -1689,7 +1722,7 @@
 element must further adhere to the syntax of an extension designation as
 defined by <a href="#extension-designations"><b>E.1 Extension Designations</b></a>,
 while the URI expressed by the <code>extends</code> attribute and/or the
-<code>restricts</code> attribute must ahdere to the syntax of a feature designation
+<code>restricts</code> attribute must adhere to the syntax of a feature designation
 or an extension designation as defined by <a href="#feature-designations"><b>D.1 Feature Designations</b></a> or
 <a href="#extension-designations"><b>E.1 Extension Designations</b></a>, respectively.</p><p>If the URI expressed by the content of the <code>ttp:extension</code> element,
 by the <code>extends</code> attribute, or by the <code>restricts</code> attribute
@@ -1759,7 +1792,7 @@
 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 TTML transformation profile and
 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-contentProfiles"><b>6.2.3 ttp:contentProfiles</b></a></p></li><li><p><a href="#parameter-attribute-contentProfileCombination"><b>6.2.4 ttp:contentProfileCombination</b></a></p></li><li><p><a href="#parameter-attribute-dropMode"><b>6.2.5 ttp:dropMode</b></a></p></li><li><p><a href="#parameter-attribute-frameRate"><b>6.2.6 ttp:frameRate</b></a></p></li><li><p><a href="#parameter-attribute-frameRateMultiplier"><b>6.2.7 ttp:frameRateMultiplier</b></a></p></li><li><p><a href="#parameter-attribute-inferProcessorProfileMethod"><b>6.2.8 ttp:inferProcessorProfileMethod</b></a></p></li><li><p><a href="#parameter-attribute-inferProcessorProfileSource"><b>6.2.9 ttp:inferProcessorProfileSource</b></a></p></li><li><p><a href="#parameter-attribute-markerMode"><b>6.2.10 ttp:markerMode</b></a></p></li><li><p><a href="#parameter-attribute-permitFeatureNarrowing"><b>6.2.11 ttp:permitFeatureNarrowing</b></a></p></li><li><p><a href="#parameter-attribute-permitFeatureWidening"><b>6.2.12 ttp:permitFeatureWidening</b></a></p></li><li><p><a href="#parameter-attribute-pixelAspectRatio"><b>6.2.13 ttp:pixelAspectRatio</b></a></p></li><li><p><a href="#parameter-attribute-profile"><b>6.2.14 ttp:profile</b></a></p></li><li><p><a href="#parameter-attribute-processorProfiles"><b>6.2.15 ttp:processorProfiles</b></a></p></li><li><p><a href="#parameter-attribute-processorProfileCombination"><b>6.2.16 ttp:processorProfileCombination</b></a></p></li><li><p><a href="#parameter-attribute-subFrameRate"><b>6.2.17 ttp:subFrameRate</b></a></p></li><li><p><a href="#parameter-attribute-tickRate"><b>6.2.18 ttp:tickRate</b></a></p></li><li><p><a href="#parameter-attribute-timeBase"><b>6.2.19 ttp:timeBase</b></a></p></li><li><p><a href="#parameter-attribute-validation"><b>6.2.20 ttp:validation</b></a></p></li><li><p><a href="#parameter-attribute-validationAction"><b>6.2.21 ttp:validationAction</b></a></p></li><li><p><a href="#parameter-attribute-version"><b>6.2.22 ttp:version</b></a></p></li></ul><p>Unless explicitly stated otherwise, linear white-space (LWSP) must
+<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-contentProfiles"><b>6.2.3 ttp:contentProfiles</b></a></p></li><li><p><a href="#parameter-attribute-contentProfileCombination"><b>6.2.4 ttp:contentProfileCombination</b></a></p></li><li><p><a href="#parameter-attribute-dropMode"><b>6.2.5 ttp:dropMode</b></a></p></li><li><p><a href="#parameter-attribute-frameRate"><b>6.2.6 ttp:frameRate</b></a></p></li><li><p><a href="#parameter-attribute-frameRateMultiplier"><b>6.2.7 ttp:frameRateMultiplier</b></a></p></li><li><p><a href="#parameter-attribute-inferProcessorProfileMethod"><b>6.2.8 ttp:inferProcessorProfileMethod</b></a></p></li><li><p><a href="#parameter-attribute-inferProcessorProfileSource"><b>6.2.9 ttp:inferProcessorProfileSource</b></a></p></li><li><p><a href="#parameter-attribute-markerMode"><b>6.2.10 ttp:markerMode</b></a></p></li><li><p><a href="#parameter-attribute-mediaDuration"><b>6.2.11 ttp:mediaDuration</b></a></p></li><li><p><a href="#parameter-attribute-mediaOffset"><b>6.2.12 ttp:mediaOffset</b></a></p></li><li><p><a href="#parameter-attribute-permitFeatureNarrowing"><b>6.2.13 ttp:permitFeatureNarrowing</b></a></p></li><li><p><a href="#parameter-attribute-permitFeatureWidening"><b>6.2.14 ttp:permitFeatureWidening</b></a></p></li><li><p><a href="#parameter-attribute-pixelAspectRatio"><b>6.2.15 ttp:pixelAspectRatio</b></a></p></li><li><p><a href="#parameter-attribute-profile"><b>6.2.16 ttp:profile</b></a></p></li><li><p><a href="#parameter-attribute-processorProfiles"><b>6.2.17 ttp:processorProfiles</b></a></p></li><li><p><a href="#parameter-attribute-processorProfileCombination"><b>6.2.18 ttp:processorProfileCombination</b></a></p></li><li><p><a href="#parameter-attribute-subFrameRate"><b>6.2.19 ttp:subFrameRate</b></a></p></li><li><p><a href="#parameter-attribute-tickRate"><b>6.2.20 ttp:tickRate</b></a></p></li><li><p><a href="#parameter-attribute-timeBase"><b>6.2.21 ttp:timeBase</b></a></p></li><li><p><a href="#parameter-attribute-validation"><b>6.2.22 ttp:validation</b></a></p></li><li><p><a href="#parameter-attribute-validationAction"><b>6.2.23 ttp:validationAction</b></a></p></li><li><p><a href="#parameter-attribute-version"><b>6.2.24 ttp:version</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
@@ -1769,7 +1802,6 @@
 <div class="exampleInner"><pre>
 ttp:cellResolution
   : columns rows                            // <em>columns</em> != 0; <em>rows</em> != 0
-
 columns | rows
   : <a href="#style-value-digit">&lt;digit&gt;</a>+
 </pre></div>
@@ -1790,7 +1822,7 @@
 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>6.2.19 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
+operating with time base of <code>clock</code> as defined by <a href="#parameter-attribute-timeBase"><b>6.2.21 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 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
@@ -1798,7 +1830,7 @@
   | "gps"
   | "utc"
 </pre></div>
-</td></tr></tbody></table><p>If the time base, defined by <a href="#parameter-attribute-timeBase"><b>6.2.19 ttp:timeBase</b></a>, is designated as
+</td></tr></tbody></table><p>If the time base, defined by <a href="#parameter-attribute-timeBase"><b>6.2.21 ttp:timeBase</b></a>, is designated as
 <code>clock</code>, then this parameter applies as follows: if the
 parameter's value is <code>local</code>, then time expressions are
 interpreted as local wall-clock time coordinates;
@@ -1830,13 +1862,10 @@
   : designators
   | "all(" designators ")"
   | "any(" designators ")"
-
 designators
   : designator (lwsp designator)*
-
 designator
   : xsd:anyURI
-
 lwsp
   : ( ' ' | '\t' | '\n' | '\r' )+
 </pre></div>
@@ -1863,14 +1892,14 @@
 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>6.2.19 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>
+<a href="#parameter-attribute-timeBase"><b>6.2.21 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"
   | "dropPAL"
   | "nonDrop"
 </pre></div>
-</td></tr></tbody></table><p>If the time base, defined by <a href="#parameter-attribute-timeBase"><b>6.2.19 ttp:timeBase</b></a>, is designated as
+</td></tr></tbody></table><p>If the time base, defined by <a href="#parameter-attribute-timeBase"><b>6.2.21 ttp:timeBase</b></a>, is designated as
 <code>smpte</code>, then this parameter applies as follows: if the
 parameter's value is <code>nonDrop</code>, then, within any given
 second of a time expression, frames count from 0 to
@@ -1943,7 +1972,6 @@
 <div class="exampleInner"><pre>
 ttp:frameRateMultiplier
   : numerator denominator                   // <em>numerator</em> != 0; <em>denominator</em> != 0
-
 numerator | denominator
   : <a href="#style-value-digit">&lt;digit&gt;</a>+
 </pre></div>
@@ -1991,7 +2019,7 @@
 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>6.2.19 ttp:timeBase</b></a>.</p><p>If specified and support for neither <code>#markerMode</code> nor <code>#markerMode-continuous</code> feature
+<a href="#parameter-attribute-timeBase"><b>6.2.21 ttp:timeBase</b></a>.</p><p>If specified and support for neither <code>#markerMode</code> nor <code>#markerMode-continuous</code> feature
 is required by a document's <a href="#terms-effective-processor-profile">effective processor profile</a>,
 then the specified value must be ignored and the value <code>discontinuous</code> applied.</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>
@@ -1999,7 +2027,7 @@
   : "continuous"
   | "discontinuous"
 </pre></div>
-</td></tr></tbody></table><p>If the time base, defined by <a href="#parameter-attribute-timeBase"><b>6.2.19 ttp:timeBase</b></a>, is designated as
+</td></tr></tbody></table><p>If the time base, defined by <a href="#parameter-attribute-timeBase"><b>6.2.21 ttp:timeBase</b></a>, is designated as
 <code>smpte</code>, then this parameter applies as follows: if the
 parameter's value is <code>continuous</code>, then <a href="#smpte12m">[SMPTE 12M]</a> time coordinates
 may be assumed to be linear and either monotonically increasing or
@@ -2058,7 +2086,47 @@
 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 id="parameter-attribute-permitFeatureNarrowing"></a>6.2.11 ttp:permitFeatureNarrowing</h4><p>The <code>ttp:permitFeatureNarrowing</code> attribute is used to specify whether
+<h4><a id="parameter-attribute-mediaDuration"></a>6.2.11 ttp:mediaDuration</h4><p>The <code>ttp:mediaDuration</code> attribute is used to specify the
+temporal extent (simple duration) of a <a href="#terms-related-media-object">related media object</a>.</p><p>If the temporal extent (simple duration) of the <a href="#terms-related-media-object">related media object</a> is known at authoring time, then this
+attribute should be specified; otherwise, if no <a href="#terms-related-media-object">related media object</a> applies or its
+temporal extent is unknown, then this attribute should not be specified.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-mediaDuration-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:mediaDuration</caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+ttp:mediaDuration
+  : <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>                        // restricted to <em>offset-time</em> form
+  | "indefinite"
+</pre></div>
+</td></tr></tbody></table><p>If specified, the value of this parameter must either (1) adhere to the <em>offset-time</em> form of
+a <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a> or (2) take the value <code>indefinite</code>.</p><p>If the value <code>indefinite</code> is specified, then there is no <a href="#terms-related-media-object">related media object</a>,
+the temporal extent (simple duration) of the
+<a href="#terms-related-media-object">related media object</a> is not known at the time this attribute is
+encoded, or the <a href="#terms-related-media-object">related media object</a> has no temporal end point.</p><p>If not specified, the value of this parameter must be considered
+to be <code>indefinite</code>.</p><p>A <code>ttp:mediaDuration</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>See <a href="#timing-time-value-expressions"><b>10.3 Time Value Expressions</b></a> for the
+specification of time expression syntax and semantics.</p></div></div><div class="div3">
+<h4><a id="parameter-attribute-mediaOffset"></a>6.2.12 ttp:mediaOffset</h4><p>The <code>ttp:mediaOffset</code> attribute is used to specify the
+temporal offset between the begin time of the <a href="#terms-root-temporal-extent">root temporal extent</a>
+and the begin time of a <a href="#terms-related-media-object">related media object</a> when operating in a
+<a href="#time-expression-semantics-media">Media Time Base</a>
+or a <a href="#time-expression-semantics-smpte">SMPTE Time Base</a>. It does not apply and
+must not be specified when operating in a <a href="#time-expression-semantics-clock">Clock Time Base</a>.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-mediaOffset-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:mediaOffset</caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+ttp:mediaOffset
+  : sign? <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>                  // restricted to <em>offset-time</em> form
+sign
+  : "+" | "-"
+</pre></div>
+</td></tr></tbody></table><p>If specified, the value of this parameter must adhere to the <em>offset-time</em> form of
+a <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a> optionally expressed with a sign.
+If not specified, the value of this parameter must be considered
+to be <code>0s</code>.</p><p>If no sign is specified or it is specified as <code>+</code>, then the begin time of the
+<a href="#terms-root-temporal-extent">root temporal extent</a> follows the begin time of the
+<a href="#terms-related-media-object">related media object</a>; otherwise (sign is present and
+specified as <code>-</code>), the begin time of the
+<a href="#terms-root-temporal-extent">root temporal extent</a> precedes the begin time of the
+<a href="#terms-related-media-object">related media object</a>.</p><p>A <code>ttp:mediaOffset</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>See <a href="#timing-time-value-expressions"><b>10.3 Time Value Expressions</b></a> for the
+specification of time expression syntax and semantics.</p></div></div><div class="div3">
+<h4><a id="parameter-attribute-permitFeatureNarrowing"></a>6.2.13 ttp:permitFeatureNarrowing</h4><p>The <code>ttp:permitFeatureNarrowing</code> attribute is used to specify whether
 requirements related to a feature or extension may be satisfied by a (syntactically or semantically) narrower interpretation
 of the feature or extension.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-permitFeatureNarrowing-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:permitFeatureNarrowing</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
@@ -2071,7 +2139,7 @@
 by a more narrowly defined feature or extension specified by an <code>extends</code> attribute.</p><p>If not specified, the value of this parameter must be considered
 to be <code>false</code>.</p><p>A <code>ttp:permitFeatureNarrowing</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p></div><div class="div3">
-<h4><a id="parameter-attribute-permitFeatureWidening"></a>6.2.12 ttp:permitFeatureWidening</h4><p>The <code>ttp:permitFeatureWidening</code> attribute is used to specify whether
+<h4><a id="parameter-attribute-permitFeatureWidening"></a>6.2.14 ttp:permitFeatureWidening</h4><p>The <code>ttp:permitFeatureWidening</code> attribute is used to specify whether
 requirements related to a feature or extension may be satisfied by a (syntactically or semantically) wider interpretation
 of the feature or extension.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-permitFeatureWidening-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:permitFeatureWidening</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
@@ -2084,13 +2152,12 @@
 by a more widely defined feature or extension specified by an <code>restricts</code> attribute.</p><p>If not specified, the value of this parameter must be considered
 to be <code>false</code>.</p><p>A <code>ttp:permitFeatureWidening</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p></div><div class="div3">
-<h4><a id="parameter-attribute-pixelAspectRatio"></a>6.2.13 ttp:pixelAspectRatio</h4><p>The <code>ttp:pixelAspectRatio</code> attribute may be used by a content author
+<h4><a id="parameter-attribute-pixelAspectRatio"></a>6.2.15 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><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
-
 width | height
   : <a href="#style-value-digit">&lt;digit&gt;</a>+
 </pre></div>
@@ -2099,9 +2166,9 @@
 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 id="parameter-attribute-profile"></a>6.2.14 ttp:profile</h4><p>The <code>ttp:profile</code> attribute is <span class="deprecated">deprecated</span>. If creating a TTML document instance for TTML2 (or later versions),
+<h4><a id="parameter-attribute-profile"></a>6.2.16 ttp:profile</h4><p>The <code>ttp:profile</code> attribute is <span class="deprecated">deprecated</span>. If creating a TTML document instance for TTML2 (or later versions),
 then the <code>ttp:profile</code> attribute should not be used; instead, the content author should use the <code>ttp:processorProfiles</code>
-attribute, specified at <a href="#parameter-attribute-processorProfiles"><b>6.2.15 ttp:processorProfiles</b></a>.</p><p>If used in a document, the <code>ttp:profile</code> attribute
+attribute, specified at <a href="#parameter-attribute-processorProfiles"><b>6.2.17 ttp:processorProfiles</b></a>.</p><p>If used in a document, the <code>ttp:profile</code> attribute
 denotes a <a href="#terms-processor-profile">processor profile</a>
 of the Timed Text Markup Language (TTML) that applies when processing
 a <a href="#terms-document-instance">document instance</a>.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>For information on signaling content profile(s), see <a href="#parameter-attribute-contentProfiles"><b>6.2.3 ttp:contentProfiles</b></a>.</p></div><p>If specified, the value of this attribute must adhere to the following syntax
@@ -2113,7 +2180,6 @@
 <div class="exampleInner"><pre>
 <span class="deprecated">ttp:profile</span>
   : designator
-
 designator
   : xsd:anyURI
 </pre></div>
@@ -2123,7 +2189,7 @@
 is defined in a <a href="#terms-document-instance">document instance</a>, then the
 <a href="#parameter-attribute-profile"><code>ttp:profile</code></a>
 attribute should not be specified on the <code>tt</code> element.</p></div><div class="div3">
-<h4><a id="parameter-attribute-processorProfiles"></a>6.2.15 ttp:processorProfiles</h4><p>The <code>ttp:processorProfiles</code> attribute may be used by a content author
+<h4><a id="parameter-attribute-processorProfiles"></a>6.2.17 ttp:processorProfiles</h4><p>The <code>ttp:processorProfiles</code> attribute may be used by a content author
 to express one or more <a href="#terms-processor-profile">processor profiles</a> of
 the Timed Text Markup Language (TTML) where the
 <a href="#terms-enclosing-document-instance">enclosing document instance</a> requires support for each and all
@@ -2136,13 +2202,10 @@
   : designators
   | "all(" designators ")"
   | "any(" designators ")"
-
 designators
   : designator (lwsp designator)*
-
 designator
   : xsd:anyURI
-
 lwsp
   : ( ' ' | '\t' | '\n' | '\r' )+
 </pre></div>
@@ -2152,7 +2215,7 @@
 of the designated <a href="#terms-processor-profile">processor profiles</a>.</p><p>A <code>ttp:processorProfiles</code>
 attribute is considered to be significant only when specified on the
 <code>tt</code> element.</p></div><div class="div3">
-<h4><a id="parameter-attribute-processorProfileCombination"></a>6.2.16 ttp:processorProfileCombination</h4><p>The <code>ttp:processorProfileCombination</code> attribute is used to specify the
+<h4><a id="parameter-attribute-processorProfileCombination"></a>6.2.18 ttp:processorProfileCombination</h4><p>The <code>ttp:processorProfileCombination</code> attribute is used to specify the
 method for combining multiple <a href="#terms-processor-profile">processor profiles</a>.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-processorProfileCombination-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:processorProfileCombination</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:processorProfileCombination
@@ -2165,7 +2228,7 @@
 of arguments is determined in accordance with the lexical order of
 <a href="#terms-processor-profile">processor profiles</a> in a <a href="#terms-document-instance">document instance</a>.</p><a id="processor-profile-combination-table"></a><table class="common"><caption>Table 6-3 – Processor Profile Combination</caption><col width="16.67%" span="1"><col width="16.67%" span="1"><col width="22%" span="1"><col width="22%" span="1"><col width="22%" span="1"><tbody><tr><th><em>arg1</em></th><th><em>arg2</em></th><th><code>leastRestrictive</code></th><th><code>mostRestrictive</code></th><th><code>replace</code></th></tr><tr><td>optional</td><td>optional</td><td>optional</td><td>optional</td><td>optional</td></tr><tr><td>optional</td><td>required</td><td>optional</td><td>required</td><td>required</td></tr><tr><td>required</td><td>optional</td><td>optional</td><td>required</td><td>optional</td></tr><tr><td>required</td><td>required</td><td>required</td><td>required</td><td>required</td></tr></tbody></table><p>A <code>ttp:processorProfileCombination</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p></div><div class="div3">
-<h4><a id="parameter-attribute-subFrameRate"></a>6.2.17 ttp:subFrameRate</h4><p>The <code>ttp:subFrameRate</code> attribute is used to specify the sub-frame rate of a related
+<h4><a id="parameter-attribute-subFrameRate"></a>6.2.19 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 <a href="#terms-document-instance">document instance</a> 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>
@@ -2184,7 +2247,7 @@
 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 id="parameter-attribute-tickRate"></a>6.2.18 ttp:tickRate</h4><p>The <code>ttp:tickRate</code> attribute is used to specify the tick rate of a related
+<h4><a id="parameter-attribute-tickRate"></a>6.2.20 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 <a href="#terms-document-instance">document instance</a> 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>
@@ -2209,7 +2272,7 @@
 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 id="parameter-attribute-timeBase"></a>6.2.19 ttp:timeBase</h4><p>The <code>ttp:timeBase</code> attribute is used to specify the
+<h4><a id="parameter-attribute-timeBase"></a>6.2.21 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 <a href="#terms-document-instance">document instance</a>.</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>
@@ -2255,23 +2318,26 @@
 given <a href="#terms-document-instance">document instance</a>, the interpretation of time expressions
 is uniform throughout the <a href="#terms-document-instance">document instance</a>.</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 class="div3">
-<h4><a id="parameter-attribute-validation"></a>6.2.20 ttp:validation</h4><p>The <code>ttp:validation</code> attribute is used to specify whether validation processing
+<h4><a id="parameter-attribute-validation"></a>6.2.22 ttp:validation</h4><p>The <code>ttp:validation</code> attribute is used to specify whether validation processing
 may or must be performed on a <a href="#terms-document-instance">document instance</a> by a
 <a href="#terms-validating-content-processor">validating content processor</a>.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-validation-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:validation</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
 ttp:validation
-  : "optional"
-  | "required"
-</pre></div>
-</td></tr></tbody></table><p>If this parameter's value is <code>optional</code>, then, a <a href="#terms-validating-content-processor">validating content processor</a>
+  : "required"
+  | "optional"
+  | "prohibited"
+</pre></div>
+</td></tr></tbody></table><p>If this parameter's value is <code>required</code>, then, a <a href="#terms-validating-content-processor">validating content processor</a>
+must perform validation processing on a TTML <a href="#terms-document-instance">document instance</a> prior to performing
+other types of processing, e.g., presentation or transformation processing.</p><p>If this parameter's value is <code>optional</code>, then, a <a href="#terms-validating-content-processor">validating content processor</a>
 may, but need not, perform validation processing on a TTML <a href="#terms-document-instance">document instance</a> prior to performing
-other types of processing, e.g., presentation or transformation processing.</p><p>If this parameter's value is <code>required</code>, then, a <a href="#terms-validating-content-processor">validating content processor</a>
-must perform validation processing on a TTML <a href="#terms-document-instance">document instance</a> prior to performing
-other types of processing, e.g., presentation or transformation processing.</p><p>If validation processing is performed on a TTML <a href="#terms-document-instance">document instance</a> and validation fails, then the computed value of
+other types of processing, e.g., presentation or transformation processing.</p><p>If this parameter's value is <code>prohibited</code>, then, a <a href="#terms-validating-content-processor">validating content processor</a>
+must not perform validation processing on a TTML <a href="#terms-document-instance">document instance</a> prior to performing
+other types of processing, e.g., presentation or transformation processing, unless the end-user or application overrides this prohibition.</p><p>If validation processing is performed on a TTML <a href="#terms-document-instance">document instance</a> and validation fails, then the computed value of
 the <code>ttp:validationAction</code> parameter property is used to determine what action to take before performing further processing.</p><p>If not specified, the value of this parameter must be considered
 to be <code>optional</code>.</p><p>A <code>ttp:validation</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p></div><div class="div3">
-<h4><a id="parameter-attribute-validationAction"></a>6.2.21 ttp:validationAction</h4><p>The <code>ttp:validationAction</code> attribute is used to specify what action is to be taken
+<h4><a id="parameter-attribute-validationAction"></a>6.2.23 ttp:validationAction</h4><p>The <code>ttp:validationAction</code> attribute is used to specify what action is to be taken
 by a <a href="#terms-validating-content-processor">validating content processor</a> when
 validation of a <a href="#terms-document-instance">document instance</a> fails.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-validationAction-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:validationAction</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
@@ -2284,10 +2350,14 @@
 must abort processing of a TTML <a href="#terms-document-instance">document instance</a> when validation processing fails.</p><p>If this parameter's value is <code>warn</code>, then, a <a href="#terms-validating-content-processor">validating content processor</a>
 should warn the end-user when validation processing fails, and, give the end-user the option to continue or abort processing.</p><p>If this parameter's value is <code>ignore</code>, then, a <a href="#terms-validating-content-processor">validating content processor</a>
 should not abort and should not warn the end-user when validation processing fails.</p><p>If not specified, the value of this parameter is determined as follows:
-if the computed value of the <a href="#parameter-attribute-validation"><code>ttp:validation</code></a> parameter property is <code>optional</code>,
-then the value must be considered to be <code>warn</code>; otherwise, it must be considered to be <code>abort</code>.</p><p>A <code>ttp:validationAction</code> attribute is considered to be significant only
+if the computed value of the <a href="#parameter-attribute-validation"><code>ttp:validation</code></a> parameter property is <code>required</code>,
+then the value must be considered to be <code>abort</code>;
+if it is <code>optional</code>,
+then the value must be considered to be <code>warn</code>;
+otherwise, if it is <code>prohibited</code>,
+then the value must be considered to be <code>ignore</code>.</p><p>A <code>ttp:validationAction</code> attribute is considered to be significant only
 when specified on the <code>tt</code> element.</p></div><div class="div3">
-<h4><a id="parameter-attribute-version"></a>6.2.22 ttp:version</h4><p>The <code>ttp:version</code> attribute is used to specify which version of the
+<h4><a id="parameter-attribute-version"></a>6.2.24 ttp:version</h4><p>The <code>ttp:version</code> attribute is used to specify which version of the
 <a href="#terms-timed-text-markup-language">Timed Text Markup Language</a>
 specification was used in authoring a TTML <a href="#terms-document-instance">document instance</a>.</p><p>If specified, the value of this attribute must adhere to the following syntax:</p><a id="parameter-attribute-version-syntax"></a><table class="syntax"><caption>Syntax Representation – ttp:version</caption><tbody><tr><td>
 <div class="exampleInner"><pre>
@@ -2324,6 +2394,7 @@
   <a href="#content-attribute-lang"><span class="reqattr">xml:lang</span></a> = string
   <a href="#content-attribute-space">xml:space</a> = (<em>default</em>|<em>preserve</em>) : default
   {<em>any attribute in TT Parameter namespace</em>}
+  {<em>any attribute in TT Style namespace</em>}
   {<em>any attribute not in default or any TT namespace</em>}&gt;
   <em>Content:</em> <a href="#document-structure-vocabulary-head">head</a>?, <a href="#document-structure-vocabulary-body">body</a>?
 &lt;/tt&gt;
@@ -2342,7 +2413,9 @@
 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="#cea708e">[CEA-708-E]</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.
+the semantics of <a href="#cea708e">[CEA-708-E]</a> , §4.5 “Caption Service Metadata”, “ASPECT RATIO”.</p></div><p>Except for the <code>tts:extent</code> attribute described above, an attribute in the TT Style Namespace should not be specified on the <code>tt</code> element
+unless it denotes an inheritable style property, and, if specified, must be ignored for the purpose of non-validation processing. In the case of validation
+processing, such usage should be reported as a warning, or, if strict validation is performed, as an error.</p><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 <a href="#terms-document-instance">document instance</a>.</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">
@@ -2650,24 +2723,49 @@
 <code>&lt;?xml-stylesheet ... ?&gt;</code> processing instruction is defined
 by this specification.</p><div class="div2">
 <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
-<a href="#terms-document-instance">document instance</a>:</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">
+<a href="#terms-document-instance">document instance</a>:</p><ul><li><p><a href="#styling-vocabulary-styling"><b>8.1.1 styling</b></a></p></li><li><p><a href="#styling-vocabulary-initial"><b>8.1.2 initial</b></a></p></li><li><p><a href="#styling-vocabulary-style"><b>8.1.3 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><a id="elt-syntax-styling"></a><table class="syntax"><caption>XML Representation – Element Information Item: styling</caption><tbody><tr><td>
+elements in the <code>Metadata.class</code> element group,
+followed by zero or more <code>initial</code> elements,
+followed by 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
   <a href="#content-attribute-lang">xml:lang</a> = string
   <a href="#content-attribute-space">xml:space</a> = (<em>default</em>|<em>preserve</em>)
   {<em>any attribute not in default or any TT namespace</em>}&gt;
-  <em>Content:</em> <a href="#element-vocab-group-table">Metadata.class</a>*, <a href="#styling-vocabulary-style">style</a>*
+  <em>Content:</em> <a href="#element-vocab-group-table">Metadata.class</a>*, <a href="#styling-vocabulary-initial">initial</a>*, <a href="#styling-vocabulary-style">style</a>*
 &lt;/styling&gt;
 </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 <a href="#terms-root-temporal-extent">root temporal extent</a>.</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
+<h4><a id="styling-vocabulary-initial"></a>8.1.2 initial</h4><p>The <code>initial</code> element is used to modify the initial value of one or more style properties, i.e, to specify use of different value(s) than
+the specification defined initial value(s).</p><p>The <code>initial</code> element accepts as its children zero or more <code>metadata</code> elements.</p><a id="elt-syntax-initial"></a><table class="syntax"><caption>XML Representation – Element Information Item: initial</caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+&lt;initial
+  <a href="#content-attribute-id">xml:id</a> = ID
+  <a href="#content-attribute-lang">xml:lang</a> = string
+  <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> <a href="#element-vocab-group-table">Metadata.class</a>*
+&lt;/initial&gt;
+</pre></div>
+</td></tr></tbody></table><p>The <code>initial</code> element is illustrated by the following example, wherein
+the initial value of the <code>tts:color</code> property is defined to be <code>yellow</code>.</p><a id="style-vocabulary-initial-example-1"></a><table class="example"><caption>Example Fragment – <code>initial</code></caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+...
+&lt;head&gt;
+  &lt;styling&gt;
+    <span class="strong">&lt;initial tts:color="yellow"/&gt;</span>
+  &lt;styling&gt;
+&lt;head&gt;
+...
+</pre></div>
+</td></tr></tbody></table></div><div class="div3">
+<h4><a id="styling-vocabulary-style"></a>8.1.3 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><a id="elt-syntax-style"></a><table class="syntax"><caption>XML Representation – Element Information Item: style</caption><tbody><tr><td>
@@ -2692,15 +2790,20 @@
 <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 certain animation elements, <a href="#terms-content-element">content elements</a>, certain layout elements, and style definition 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 <a href="#terms-content-element">content elements</a>
-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-border"><b>8.2.3 tts:border</b></a></p></li><li><p><a href="#style-attribute-color"><b>8.2.4 tts:color</b></a></p></li><li><p><a href="#style-attribute-direction"><b>8.2.5 tts:direction</b></a></p></li><li><p><a href="#style-attribute-display"><b>8.2.6 tts:display</b></a></p></li><li><p><a href="#style-attribute-displayAlign"><b>8.2.7 tts:displayAlign</b></a></p></li><li><p><a href="#style-attribute-extent"><b>8.2.8 tts:extent</b></a></p></li><li><p><a href="#style-attribute-fontFamily"><b>8.2.9 tts:fontFamily</b></a></p></li><li><p><a href="#style-attribute-fontSize"><b>8.2.10 tts:fontSize</b></a></p></li><li><p><a href="#style-attribute-fontStyle"><b>8.2.11 tts:fontStyle</b></a></p></li><li><p><a href="#style-attribute-fontWeight"><b>8.2.12 tts:fontWeight</b></a></p></li><li><p><a href="#style-attribute-lineHeight"><b>8.2.13 tts:lineHeight</b></a></p></li><li><p><a href="#style-attribute-opacity"><b>8.2.14 tts:opacity</b></a></p></li><li><p><a href="#style-attribute-origin"><b>8.2.15 tts:origin</b></a></p></li><li><p><a href="#style-attribute-overflow"><b>8.2.16 tts:overflow</b></a></p></li><li><p><a href="#style-attribute-padding"><b>8.2.17 tts:padding</b></a></p></li><li><p><a href="#style-attribute-showBackground"><b>8.2.18 tts:showBackground</b></a></p></li><li><p><a href="#style-attribute-textAlign"><b>8.2.19 tts:textAlign</b></a></p></li><li><p><a href="#style-attribute-textDecoration"><b>8.2.20 tts:textDecoration</b></a></p></li><li><p><a href="#style-attribute-textOrientation"><b>8.2.21 tts:textOrientation</b></a></p></li><li><p><a href="#style-attribute-textOutline"><b>8.2.22 tts:textOutline</b></a></p></li><li><p><a href="#style-attribute-unicodeBidi"><b>8.2.23 tts:unicodeBidi</b></a></p></li><li><p><a href="#style-attribute-visibility"><b>8.2.24 tts:visibility</b></a></p></li><li><p><a href="#style-attribute-wrapOption"><b>8.2.25 tts:wrapOption</b></a></p></li><li><p><a href="#style-attribute-writingMode"><b>8.2.26 tts:writingMode</b></a></p></li><li><p><a href="#style-attribute-zIndex"><b>8.2.27 tts:zIndex</b></a></p></li></ul><table border="1" class="ednote" summary="Editorial note: Additional Border Styling Attributes"><tr class="ednote-r1"><td align="left" valign="top"><b>Editorial note: Additional Border Styling Attributes</b></td><td align="right" valign="top">2013-08-24</td></tr><tr class="ednote-r2"><td colspan="2" align="left" valign="top">Consider adding support for <code>tts:borderColor</code>, <code>tts:borderStyle</code>, and <code>tts:borderWidth</code>
+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-border"><b>8.2.3 tts:border</b></a></p></li><li><p><a href="#style-attribute-color"><b>8.2.4 tts:color</b></a></p></li><li><p><a href="#style-attribute-direction"><b>8.2.5 tts:direction</b></a></p></li><li><p><a href="#style-attribute-display"><b>8.2.6 tts:display</b></a></p></li><li><p><a href="#style-attribute-displayAlign"><b>8.2.7 tts:displayAlign</b></a></p></li><li><p><a href="#style-attribute-extent"><b>8.2.8 tts:extent</b></a></p></li><li><p><a href="#style-attribute-fontFamily"><b>8.2.9 tts:fontFamily</b></a></p></li><li><p><a href="#style-attribute-fontSize"><b>8.2.10 tts:fontSize</b></a></p></li><li><p><a href="#style-attribute-fontStyle"><b>8.2.11 tts:fontStyle</b></a></p></li><li><p><a href="#style-attribute-fontWeight"><b>8.2.12 tts:fontWeight</b></a></p></li><li><p><a href="#style-attribute-lineHeight"><b>8.2.13 tts:lineHeight</b></a></p></li><li><p><a href="#style-attribute-opacity"><b>8.2.14 tts:opacity</b></a></p></li><li><p><a href="#style-attribute-origin"><b>8.2.15 tts:origin</b></a></p></li><li><p><a href="#style-attribute-overflow"><b>8.2.16 tts:overflow</b></a></p></li><li><p><a href="#style-attribute-padding"><b>8.2.17 tts:padding</b></a></p></li><li><p><a href="#style-attribute-ruby"><b>8.2.18 tts:ruby</b></a></p></li><li><p><a href="#style-attribute-rubyAlign"><b>8.2.19 tts:rubyAlign</b></a></p></li><li><p><a href="#style-attribute-rubyPosition"><b>8.2.20 tts:rubyPosition</b></a></p></li><li><p><a href="#style-attribute-showBackground"><b>8.2.21 tts:showBackground</b></a></p></li><li><p><a href="#style-attribute-textAlign"><b>8.2.22 tts:textAlign</b></a></p></li><li><p><a href="#style-attribute-textDecoration"><b>8.2.23 tts:textDecoration</b></a></p></li><li><p><a href="#style-attribute-textOrientation"><b>8.2.24 tts:textOrientation</b></a></p></li><li><p><a href="#style-attribute-textOutline"><b>8.2.25 tts:textOutline</b></a></p></li><li><p><a href="#style-attribute-unicodeBidi"><b>8.2.26 tts:unicodeBidi</b></a></p></li><li><p><a href="#style-attribute-visibility"><b>8.2.27 tts:visibility</b></a></p></li><li><p><a href="#style-attribute-wrapOption"><b>8.2.28 tts:wrapOption</b></a></p></li><li><p><a href="#style-attribute-writingMode"><b>8.2.29 tts:writingMode</b></a></p></li><li><p><a href="#style-attribute-zIndex"><b>8.2.30 tts:zIndex</b></a></p></li></ul><table border="1" class="ednote" summary="Editorial note: Additional Border Styling Attributes"><tr class="ednote-r1"><td align="left" valign="top"><b>Editorial note: Additional Border Styling Attributes</b></td><td align="right" valign="top">2013-08-24</td></tr><tr class="ednote-r2"><td colspan="2" align="left" valign="top">Consider adding support for <code>tts:borderColor</code>, <code>tts:borderStyle</code>, and <code>tts:borderWidth</code>
 in order to provide a means to independently express styling of the four different borders (top, right, bottom, left). As currently specified, i.e., with only the
-<code>tts:border</code> attribute, one can only express the four borders using the same color, style, and width.</td></tr></table><p>Unless explicitly stated otherwise, linear white-space (LWSP) must
+<code>tts:border</code> attribute, one can only express the four borders using the same color, style, and width.</td></tr></table><p>Unless explicitly permitted by an element type definition, an attribute in the TT Style Namespace should not be specified on an element
+unless it either applies to that element or denotes an inheritable style property. If it does not apply to that element
+and does not denote an inheritable style property, then it must be ignored for the purpose of non-validation processing.
+In the case of validation processing, such usage should be reported as a warning, or, if strict validation is performed,
+as an error.</p><p>Unless explicitly stated otherwise, linear white-space (LWSP) must
 appear between adjacent non-terminal components of a value of a TT
 Style 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
-properties.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>A style property may be expressed as a specified attribute on any
+properties.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>An inheritable style property may be expressed as a specified attribute on the
+root <a href="#document-structure-vocabulary-tt"><code>tt</code></a> element or on a
 <a href="#terms-content-element">content element</a> type
 independently of whether the property applies to that
 element type. This capability permits the expression of an inheritable
@@ -3367,16 +3470,13 @@
 </td></tr><tr><td><em>Initial:</em></td><td><code>hidden</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>If the value of this attribute is <code>visible</code>, then content should
-not be clipped outside of the affected region, and region composition and layout
-must be performed as if the region's width and height were
-unconstrained,
-but with
-a well-defined origin.  If the value is <code>hidden</code>, then content should
+not be clipped outside of the affected region.
+If the value is <code>hidden</code>, then content should
 be clipped outside of the affected region.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>Unless a manual line break element <code>br</code> is used by the content author,
 a paragraph of a given region will generate no more than one line area in that
-region if the value of the <code>tts:overflow</code> style that applies to the
-region is <code>visible</code> and if the applicable <code>tts:wrapOption</code>
-style is <code>noWrap</code>.</p></div><p>If a computed value of the property associated with this attribute is not supported,
+region if the computed values of the <code>tts:overflow</code> and <code>tts:wrapOption</code>
+style properties of the region are <code>visible</code> and <code>noWrap</code>,
+respectively.</p></div><p>If a computed value of the property associated with this attribute is not supported,
 then a <a href="#terms-presentation-processor">presentation processor</a> must use the value <code>hidden</code>.</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;
@@ -3471,7 +3571,90 @@
 § 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>8.2.18 tts:showBackground</h4><p>The <code>tts:showBackground</code> attribute is used to specify
+<h4><a id="style-attribute-ruby"></a>8.2.18 tts:ruby</h4><p>The <code>tts:ruby</code> attribute is used to specify the application of ruby
+styling.</p><p>This attribute applies only to <a href="#content-vocabulary-span"><code>span</code></a> elements and is not inheritable, so it should
+not be specified on any other element type. If specified elsewhere, then it must be ignored for
+the purpose of presentation processing.</p><a id="style-property-details-ruby"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
+<code>none</code> |
+<code>container</code> |
+<code>base</code> |
+<code>baseContainer</code> |
+<code>text</code> |
+<code>textContainer</code> |
+<code>delimiter</code>
+</td></tr><tr><td><em>Initial:</em></td><td><code>none</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>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></p><p>If the value of this attribute is <code>none</code>, then no ruby semantics apply; otherwise, the ruby semantics enumerated by
+<a href="#ruby-semantics-mapping-table"><b>Table 8-1 – Ruby Semantics Mapping</b></a> apply, where the maximal content model defined by <a href="#ruby">[Ruby]</a>, §2.1, applies
+and must be treated as an error if violated.</p><p>If a computed value of the property associated with this attribute is not supported,
+then a <a href="#terms-presentation-processor">presentation processor</a> must use the value <code>none</code>.</p><a id="ruby-semantics-mapping-table"></a><table class="common"><caption>Table 8-1 – Ruby Semantics Mapping</caption><col width="25%" span="1"><col width="25%" span="1"><col width="25%" span="1"><col width="25%" span="1"><col span="1"><tbody><tr><th>Category</th><th>tts:ruby</th><th>Annotation <a href="#ruby">[Ruby]</a></th><th>CSS display <a href="#cssruby">[CSS Ruby]</a></th></tr><tr><td>Ruby Container</td><td><code>container</code></td><td><code>ruby</code></td><td><code>ruby</code></td></tr><tr><td>Ruby Base Content</td><td><code>base</code></td><td><code>rb</code></td><td><code>ruby-base</code></td></tr><tr><td>Ruby Text Content</td><td><code>text</code></td><td><code>rt</code></td><td><code>ruby-text</code></td></tr><tr><td>Ruby Base Container</td><td><code>baseContainer</code></td><td><code>rbc</code></td><td><code>ruby-base-container</code></td></tr><tr><td>Ruby Text Container</td><td><code>textContainer</code></td><td><code>rtc</code></td><td><code>ruby-text-container</code></td></tr><tr><td>Ruby Fallback Delimiter</td><td><code>delimiter</code></td><td><code>rp</code></td><td><code>none</code></td></tr></tbody></table><p>Use of <code>tts:ruby</code> to specify simple ruby annotation is illustrated by the following example.</p><a id="style-attribute-ruby-example-1"></a><table class="example"><caption>Example Fragment – Simple Ruby</caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+&lt;span <span class="strong">tts:ruby="container"</span>&gt;
+  &lt;span <span class="strong">tts:ruby="base"</span>&gt;利用許諾&lt;/span&gt;
+  &lt;span <span class="strong">tts:ruby="text"</span>&gt;ライセンス&lt;/span&gt;
+&lt;/span&gt;
+</pre></div>
+</td></tr></tbody></table><p></p><a id="style-attribute-ruby-example-1-images"></a><table class="example-images"><caption>Example Rendition – Simple Ruby</caption><tbody><tr><td><img src="images/ruby_1.png" alt="TTML ruby style property"></td></tr></tbody></table><p>Use of <code>tts:ruby</code> to specify complex ruby annotation is illustrated by the following example.</p><a id="style-attribute-ruby-example-2"></a><table class="example"><caption>Example Fragment – Complex Ruby</caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+&lt;span&gt;
+  &lt;span <span class="strong">tts:ruby="container"</span>&gt;
+    &lt;span <span class="strong">tts:ruby="baseContainer"</span>&gt;
+      &lt;span <span class="strong">tts:ruby="base"</span>&gt;東南&lt;/span&gt;
+    &lt;/span&gt;
+    &lt;span <span class="strong">tts:ruby="textContainer"</span> tts:rubyPosition="before"&gt;
+      &lt;span <span class="strong">tts:ruby="text"</span>&gt;とうなん&lt;/span&gt;
+    &lt;/span&gt;
+    &lt;span <span class="strong">tts:ruby="textContainer"</span> tts:rubyPosition="after"&gt;
+      &lt;span <span class="strong">tts:ruby="text"</span>&gt;たつみ&lt;/span&gt;
+    &lt;/span&gt;
+  &lt;/span&gt;
+  &lt;span&gt;の方角&lt;/span&gt;
+&lt;/span&gt;
+</pre></div>
+</td></tr></tbody></table><p></p><a id="style-attribute-ruby-example-2-images"></a><table class="example-images"><caption>Example Rendition – Complex Ruby</caption><tbody><tr><td><img src="images/ruby_2.png" alt="TTML ruby 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="#ruby">[Ruby]</a> and <a href="#cssruby">[CSS Ruby]</a>. See also
+<a href="#jlreq">[JLREQ]</a>, §3.3, for further information.</p></div></div><div class="div3">
+<h4><a id="style-attribute-rubyAlign"></a>8.2.19 tts:rubyAlign</h4><p>The <code>tts:rubyAlign</code> attribute is used to specify the position of ruby text within the inline area generated by the ruby text container annotation.</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 <a href="#content-vocabulary-span"><code>span</code></a> elements on which the computed value of the
+<code>tts:ruby</code> style property is either <code>textContainer</code> or <code>text</code>.</p><a id="style-property-details-rubyAlign"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
+<code>start</code> |
+<code>center</code> |
+<code>spaceBetween</code> |
+<code>spaceAround</code>
+</td></tr><tr><td><em>Initial:</em></td><td><code>spaceAround</code></td></tr><tr><td><em>Applies to:</em></td><td>
+<em>see prose (above)</em>
+</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></p><p>If the value of this attribute is <code>start</code>, then the start edge of the first glyph area descendant of an inline area generated from a ruby text container
+or ruby text annotation is aligned to the start edge of that inline area.
+If the value is <code>center</code>, then excess whitespace
+is equally distributed before and after the first and last glyphs, respectively.
+If the value is <code>spaceBetween</code>, then excess whitespace
+is equally distributed between each glyph area descendant.
+If the value is <code>spaceAround</code>, then excess whitespace
+is equally distributed before and after each glyph area descendant.</p><p>If a computed value of the property associated with this attribute is not supported,
+then a <a href="#terms-presentation-processor">presentation processor</a> must use the value <code>spaceAround</code>.</p><table border="1" class="ednote" summary="Editorial note: Ruby Align Example"><tr class="ednote-r1"><td align="left" valign="top"><b>Editorial note: Ruby Align Example</b></td><td align="right" valign="top">2014-09-20</td></tr><tr class="ednote-r2"><td colspan="2" align="left" valign="top">Add example and example rendering of tts:rubyAlign.</td></tr></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="#cssruby">[CSS Ruby]</a>, §4.3, and the examples and example
+renderings shown there apply.</p></div></div><div class="div3">
+<h4><a id="style-attribute-rubyPosition"></a>8.2.20 tts:rubyPosition</h4><p>The <code>tts:rubyPosition</code> attribute is used to specify the position of ruby text in the block progression dimension
+with respect to its associated ruby base.</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 <a href="#content-vocabulary-span"><code>span</code></a> elements on which the computed value of the
+<code>tts:ruby</code> style property is either <code>textContainer</code> or <code>text</code>.</p><a id="style-property-details-rubyPosition"></a><table class="common"><col width="25%" span="1"><col span="1"><tbody><tr><td><em>Values:</em></td><td>
+<code>before</code> |
+<code>after</code> |
+<code>interCharacter</code>
+</td></tr><tr><td><em>Initial:</em></td><td><code>before</code></td></tr><tr><td><em>Applies to:</em></td><td>
+<em>see prose (above)</em>
+</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></p><p>If the value of this attribute is <code>before</code>, then an inline area generated from a ruby text container or ruby text annotation
+is placed before (prior to) the first edge in the block progression dimension of the inline area generated from an associated ruby base container or ruby base annotation.
+If the value is <code>after</code>, then an inline area generated from a ruby text container or ruby text annotation
+is placed after (subsequent to) the second edge in the block progression dimension of the inline area generated from an associated ruby base container or ruby base
+annotation.</p><p>If the value of this attribute is <code>interCharacter</code>, then an inline area generated from a ruby text container or ruby text annotation is placed
+after the end edge in the inline progression dimension of the inline area generated from an associated ruby base container or ruby base annotation.</p><p>The absolute position of the ruby text container or ruby text annotation is determined
+in accordance to the computed value of the <code>tts:writingMode</code> style property of the region into which the affected content is placed; in particular, the
+mappings defined enumerated by <a href="#rubyPosition-semantics-mapping-table"><b>Table 8-2 – Ruby Position Semantics Mapping by Writing Mode</b></a> apply as further defined by <a href="#cssruby">[CSS Ruby]</a>, §4.1.</p><p>If a computed value of the property associated with this attribute is not supported,
+then a <a href="#terms-presentation-processor">presentation processor</a> must use the value <code>before</code>.</p><a id="rubyPosition-semantics-mapping-table"></a><table class="common"><caption>Table 8-2 – Ruby Position Semantics Mapping by Writing Mode</caption><col width="20%" span="1"><col width="20%" span="1"><col width="20%" span="1"><col width="20%" span="1"><col width="20%" span="1"><col span="1"><tbody><tr><th>tts:rubyPosition</th><th><code>lrtb</code></th><th><code>rltb</code></th><th><code>tbrl</code></th><th><code>tblr</code></th></tr><tr><td><code>before</code></td><td><code>over</code></td><td><code>over</code></td><td><code>right</code></td><td><code>left</code></td></tr><tr><td><code>after</code></td><td><code>under</code></td><td><code>under</code></td><td><code>left</code></td><td><code>right</code></td></tr><tr><td><code>interCharacter</code></td><td><code>right</code></td><td><code>left</code></td><td><code>under</code></td><td><code>under</code></td></tr></tbody></table><p></p><table border="1" class="ednote" summary="Editorial note: Ruby Position Example"><tr class="ednote-r1"><td align="left" valign="top"><b>Editorial note: Ruby Position Example</b></td><td align="right" valign="top">2014-09-20</td></tr><tr class="ednote-r2"><td colspan="2" align="left" valign="top">Add example and example rendering of tts:rubyPosition.</td></tr></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="#cssruby">[CSS Ruby]</a>, §4.1, and the examples and example
+renderings shown there apply modulo the mappings defined above.</p></div></div><div class="div3">
+<h4><a id="style-attribute-showBackground"></a>8.2.21 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
@@ -3512,7 +3695,7 @@
 </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="#smil3">[SMIL 3.0]</a>,
 § 7.4.2.</p></div></div><div class="div3">
-<h4><a id="style-attribute-textAlign"></a>8.2.19 tts:textAlign</h4><p>The <code>tts:textAlign</code> attribute is used to specify a style property that
+<h4><a id="style-attribute-textAlign"></a>8.2.22 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
@@ -3555,7 +3738,7 @@
 </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>8.2.20 tts:textDecoration</h4><p>The <code>tts:textDecoration</code> attribute is used to specify a style property that
+<h4><a id="style-attribute-textDecoration"></a>8.2.23 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
@@ -3604,7 +3787,7 @@
 </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-textOrientation"></a>8.2.21 tts:textOrientation</h4><p>The <code>tts:textOrientation</code> attribute is used to specify a style property that
+<h4><a id="style-attribute-textOrientation"></a>8.2.24 tts:textOrientation</h4><p>The <code>tts:textOrientation</code> attribute is used to specify a style property that
 defines a text orientation to apply to glyphs that are selected for glyph areas generated
 by content flowed into a region to which a vertical writing mode applies.</p><p>This attribute may be specified by any
 element type
@@ -3639,7 +3822,7 @@
 example.</p><table border="1" class="ednote" summary="Editorial note: Text Orientation Example"><tr class="ednote-r1"><td align="left" valign="top"><b>Editorial note: Text Orientation Example</b></td><td align="right" valign="top">2013-08-24</td></tr><tr class="ednote-r2"><td colspan="2" align="left" valign="top">Insert example fragment and image of text orientation.</td></tr></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-wm">[CSS Writing Modes Level 3]</a>,
 § 5.1.</p></div></div><div class="div3">
-<h4><a id="style-attribute-textOutline"></a>8.2.22 tts:textOutline</h4><p>The <code>tts:textOutline</code> attribute is used to specify a style property that
+<h4><a id="style-attribute-textOutline"></a>8.2.25 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
@@ -3688,7 +3871,7 @@
 &lt;/p&gt;
 </pre></div>
 </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="textOutline style property"></td></tr></tbody></table></div><div class="div3">
-<h4><a id="style-attribute-unicodeBidi"></a>8.2.23 tts:unicodeBidi</h4><p>The <code>tts:unicodeBidi</code> attribute is used to specify a style property that
+<h4><a id="style-attribute-unicodeBidi"></a>8.2.26 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
@@ -3727,7 +3910,7 @@
 </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>8.2.24 tts:visibility</h4><p>The <code>tts:visibility</code> attribute is used to specify a style property that
+<h4><a id="style-attribute-visibility"></a>8.2.27 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
@@ -3782,7 +3965,7 @@
 </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>8.2.25 tts:wrapOption</h4><p>The <code>tts:wrapOption</code> attribute is used to specify a style property that
+<h4><a id="style-attribute-wrapOption"></a>8.2.28 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
@@ -3816,7 +3999,7 @@
 </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>8.2.26 tts:writingMode</h4><p>The <code>tts:writingMode</code> attribute is used to specify a style property that
+<h4><a id="style-attribute-writingMode"></a>8.2.29 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
@@ -3867,7 +4050,7 @@
 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>8.2.27 tts:zIndex</h4><p>The <code>tts:zIndex</code> attribute is used to specify a style property that
+<h4><a id="style-attribute-zIndex"></a>8.2.30 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
@@ -4009,19 +4192,14 @@
   | "rgb" "(" r-value "," g-value "," b-value ")"
   | "rgba" "(" r-value "," g-value "," b-value "," a-value ")"
   | <a href="#style-value-namedColor">&lt;namedColor&gt;</a>
-
 rrggbb
   :  <a href="#style-value-hexDigit">&lt;hexDigit&gt;</a>{6}
-
 rrggbbaa
   :  <a href="#style-value-hexDigit">&lt;hexDigit&gt;</a>{8}
-
 r-value | g-value | b-value | a-value
   : component-value
-
 component-value
   : non-negative-integer                    // valid range: [0,255]
-
 non-negative-integer
   : <a href="#style-value-digit">&lt;digit&gt;</a>+
 </pre></div>
@@ -4053,39 +4231,29 @@
 &lt;familyName&gt;
   : 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>
@@ -4160,29 +4328,21 @@
 &lt;length&gt;
   : scalar
   | percentage
-
 scalar
   : number units
-
 percentage
   : number "%"
-
 sign
   : "+" | "-"
-
 number
   : sign? non-negative-number
-
 non-negative-number
   : non-negative-integer
   | non-negative-real
-
 non-negative-integer
   : <a href="#style-value-digit">&lt;digit&gt;</a>+
-
 non-negative-real
   : <a href="#style-value-digit">&lt;digit&gt;</a>* "." <a href="#style-value-digit">&lt;digit&gt;</a>+
-
 units
   : "px"
   | "em"
@@ -4323,9 +4483,7 @@
 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><table border="1" class="ednote" summary="Editorial note: Layout Style Inheritance"><tr class="ednote-r1"><td align="left" valign="top"><b>Editorial note: Layout Style Inheritance</b></td><td align="right" valign="top">2013-09-05</td></tr><tr class="ednote-r2"><td colspan="2" align="left" valign="top">Regions should be able to inherit styles from a common ancestor in order to prevent
-having to full populate region styles. <a href="https://www.w3.org/AudioVideo/TT/tracker/issues/277">Issue 277</a> proposes
-inheritance from the layout element.</td></tr></table><p>For the purpose of determining inherited styles, the element hierarchy of
+</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><li><p><a href="#semantics-style-inheritance-content">root 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 <a href="#terms-document-instance">document instance</a> must be used, where
 such intermediate forms are defined by <a href="#semantics-region-layout-step-1"><b>9.3.3 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
@@ -4334,11 +4492,10 @@
 within an intermediate synchronic document
 if a style property is not associated with a <a href="#terms-content-element">content element</a> (or
 an anonymous span) and the style property is designated as
-inheritable.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The <code>tt</code> element is not a <a href="#terms-content-element">content element</a>;
-consequently, the <code>body</code> element is the outermost element from which content style inheritance occurs.</p></div><p>If a style property is determined to require inheritance, then the inherited value must
+inheritable.</p><p>If a style property is determined to require inheritance, then the inherited value must
 be the value of the same named style property in the computed
 style set of the
-element's immediate ancestor element
+element's nearest ancestor element that defines the property
 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;
@@ -4355,14 +4512,10 @@
 specified
 style
 set of the <code>span</code> element.</p></div></div><div class="div4">
-<h5><a id="semantics-style-inheritance-region"></a>8.4.2.2 Region Style Inheritance</h5><p>Style properties are inherited from a <a href="#layout-vocabulary-region">region</a> 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 <a href="#layout-vocabulary-region">region</a> element in the following case:</p><ol class="enumar"><li><p>if an inheritable style property <em>P</em> is not associated with
 a <a href="#terms-content-element">content element</a>
-or an anonymous span <em>E</em> and the style
-property is designated as inheritable, and</p></li><li><p>if that
-style property <em>P</em> is in the computed style
-set of region
-<em>R</em>,
-and</p></li><li><p>if that element <em>E</em> is flowed into (presented within) region
+or an anonymous span <em>E</em>, and</p></li><li><p>if that style property <em>P</em> is in the computed style
+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><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;
@@ -4375,7 +4528,26 @@
 </td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>In the above example, the anonymous span that encloses the character
 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">
+element into which the <code>p</code> element is flowed (presented).</p></div></div><div class="div4">
+<h5><a id="semantics-style-inheritance-root"></a>8.4.2.3 Root Style Inheritance</h5><p>Style properties are inherited from the root <a href="#document-structure-vocabulary-tt">tt</a> element in the following case:</p><ol class="enumar"><li><p>if an inheritable style property <em>P</em> is not associated with
+a <a href="#layout-vocabular-region"><code>region</code></a> element, and</p></li><li><p>if that
+style property <em>P</em> is in the computed style
+set of the root <a href="#document-structure-vocabulary-tt">tt</a> element.</p></li></ol><div class="note"><p class="prefix"><b>Note:</b></p><p>Root style inheritance provides a mechanism by means of which <code>region</code> elements
+can inherit a common style rather than repeating the specification of the style on each
+<code>region</code> element.</p></div><a id="style-inheritance-example-4"></a><table class="example"><caption>Example – Root Style Inheritance</caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+&lt;tt <span class="strong">tts:color="yellow"</span>&gt;
+...
+&lt;region xml:id="r1" <span class="strong">tts:fontFamily="monospaceSerif"</span>/&gt;
+...
+&lt;p region="r1"&gt;Yellow Monospace&lt;/p&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 <code>region</code> element inherits the
+<code>tts:color</code> style specified on the <code>tt</code> element, which,
+along with the <code>tts:fontFamily</code> style specified on the <code>region</code>
+element, are inherited by <code>p</code> element when selected into the region.</p></div></div></div><div class="div3">
 <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">
@@ -4521,23 +4693,28 @@
 <code>set</code>, then for each
 immediate animation (<code>set</code>) element child <em>A</em> of element <em>E</em>,
 merge the specified style set of <em>A</em>,
-<em>SSS(A)</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 animation element type <code>set</code>
-or the styling element type <code>style</code>,
-then for each inheritable style property
-<em>P<sub>INH</sub></em> in the set of style properties defined
+<em>SSS(A)</em>, into the specified style set of <em>E</em>, <em>SSS(E)</em>;</p></li><li><p><span class="strong">[implicit inheritance and initial value fallback]</span> if the
+element type of <em>E</em> is not animation element type <code>animate</code> or <code>set</code>
+and is not styling element type <code>style</code>,
+then for each style property
+<em>P</em> in the set of style properties defined
 above in <a href="#styling-attribute-vocabulary"><b>8.2 Styling Attribute Vocabulary</b></a>, perform the
-following ordered sub-steps:</p><ol class="enumla"><li><p>if <em>P<sub>INH</sub></em> is present in the specified
+following ordered sub-steps:</p><ol class="enumla"><li><p>if <em>P</em> is present in the specified
 style set of <em>E</em>, <em>SSS(E)</em>, then continue to the
-next inheritable style property;</p></li><li><p>if the element type of <em>E</em> is the layout element
-type <code>region</code>, then set <em>P′</em> to the initial value of
+next style property;</p></li><li><p>if <em>P</em> is defined to be inheritable and <em>E</em> is
+not the <a href="#document-structure-vocabulary-tt"><code>tt</code></a> element, then perform the following:</p><ul><li><p>if <em>E</em> is not a
+<a href="#styling-vocabulary-style"><code>style</code></a>,
+<a href="#animation-vocabulary-animate"><code>animate</code></a>, or
+<a href="#animation-vocabulary-set"><code>set</code></a> element,
+then set <em>P′</em> to the result of
+looking up the value of <em>P</em> in the computed style set of
+the nearest ancestor element of <em>E</em>, <em>NEAREST-ANCESTOR(E)</em>, such that
+<em>CSS(NEAREST-ANCESTOR(E))</em> contains a definition of <em>P</em>;</p></li></ul></li><li><p>otherwise (<em>P</em> is not inheritable or <em>E</em> is
+the <a href="#document-structure-vocabulary-tt"><code>tt</code></a> element), perform the following:</p><ul><li><p>set <em>P′</em> to the initial value of
 property <em>P</em>, where the initial value of a property is
-determined according to the specific property definition found above
-in <a href="#styling-attribute-vocabulary"><b>8.2 Styling Attribute Vocabulary</b></a>;</p></li><li><p>if the element type of <em>E</em> is a <a href="#terms-content-element">content element</a>
-type or anonymous span, then set <em>P′</em> to the result of
-looking up the value of <em>P</em> in the computed style set of
-the immediate ancestor element of <em>E</em>, i.e.,
-<em>CSS(PARENT(E))</em>;</p></li><li><p>if the value of <em>P′</em> is not undefined, then merge
+determined as follows:</p><ol class="enumlr"><li><p>if an <a href="#styling-vocabulary-initial"><code>initial</code></a>
+element defines the initial value for <em>P</em>, then use that value;</p></li><li><p>otherwise, use the initial value specified by the property definition of <em>P</em> found above
+in <a href="#styling-attribute-vocabulary"><b>8.2 Styling Attribute Vocabulary</b></a>;</p></li></ol></li></ul></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 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
@@ -4549,31 +4726,27 @@
 <a href="#semantics-style-resolution-processing-sss"><b>8.4.4.2 Specified Style Set Processing</b></a>;</p></li><li><p><span class="strong">[initialization]</span>
 initialize <em>CSS(E)</em> to a (deep) copy of
 <em>SSS(E)</em>;</p></li><li><p><span class="strong">[filter]</span> if
-<em>E</em> is a <code>set</code> or <code>style</code> element, then return
+<em>E</em> is an <code>animate</code>, <code>set</code>, or <code>style</code> element, then return
 <em>CSS(E)</em> as the resulting computed style set without
 further resolution; otherwise, continue with the next rule;</p></li><li><p><span class="strong">[relative value resolution]</span> for each
 style property <em>P</em> in <em>CSS(E)</em>, where the value
 type of <em>P</em> is relative, perform the following ordered
 sub-steps:</p><ol class="enumla"><li><p>replace the relative value of <em>P</em> with an
 equivalent, non-relative (computed) value;</p></li><li><p>set the category of <em>P</em> to "computed";</p></li></ol></li></ol><div class="note"><p class="prefix"><b>Note:</b></p><p>As a result of the filtering rule above, the computed style set of
-a <code>set</code> or <code>style</code> element includes only specified values, in which case
+an <code>animate</code>, <code>set</code>, or <code>style</code> element includes only specified values, in which case
 relative value expressions remain relative; consequently, the
 resolution of relative value expressions (that may be assigned by
 means of referential style association) always takes place in the
 context of a layout or <a href="#terms-content-element">content element</a> which has a presentation
 context, and not in the non-presentation, declaration context
-of a <code>set</code> element or a referentiable <code>style</code> element.</p></div></div><div class="div4">
+of an <code>animate</code>, <code>set</code>, or referable <code>style</code> element.</p></div></div><div class="div4">
 <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,
+a preorder traversal of each element and <em>anonymous span</em>,
 <em>E</em>, of an intermediate synchronic document,
 <em>DOC<sub>inter</sub></em>, perform the following ordered
-sub-steps:</p><ol class="enumar"><li><p><span class="strong">[filter]</span> if the element type
-of <em>E</em> is not the styling element type <code>style</code>, is
-not the layout element type <code>region</code>, is not the animation
-element type <code>set</code>, and is not one of the
-<a href="#terms-content-element">content element</a> types <code>body</code>, <code>div</code>, <code>p</code>,
-<code>span</code>, <code>br</code>, or anonymous span, then continue to the
-next element in the preorder traversal;</p></li><li><p> <span class="strong">[resolve computed styles]</span>
+sub-steps:</p><ol class="enumar"><li><p><span class="strong">[filter]</span> if <em>E</em>
+is not one of the following, then continue to the next element in the preorder traversal, i.e.,
+do not perform the subsequent step below on <em>E</em>:</p><ul><li><p><a href="#document-structure-vocabulary-tt"><code>tt</code></a></p></li><li><p><a href="#styling-vocabulary-style"><code>style</code></a></p></li><li><p><a href="#layout-vocabulary-region"><code>region</code></a></p></li><li><p><a href="#document-structure-vocabulary-body"><code>body</code></a></p></li><li><p><a href="#content-vocabulary-body"><code>div</code></a></p></li><li><p><a href="#content-vocabulary-body"><code>p</code></a></p></li><li><p><a href="#content-vocabulary-body"><code>span</code></a></p></li><li><p><a href="#content-vocabulary-body"><code>br</code></a></p></li><li><p><a href="#animation-vocabulary-animate"><code>animate</code></a></p></li><li><p><a href="#animation-vocabulary-set"><code>set</code></a></p></li><li><p><em>anonymous span</em></p></li></ul></li><li><p> <span class="strong">[resolve computed styles]</span>
 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">
@@ -4849,7 +5022,7 @@
 &lt;/tt&gt;
 </pre></div>
 </td></tr></tbody></table></div><div class="div3">
-<h4><a id="semantics-region-layout-step-1"></a>9.3.3 Intermediate Synchronic Document Construction</h4><p>For the purposes of performing presentation processing, the active time
+<h4><a id="semantics-region-layout-step-1"></a>9.3.3 Intermediate Synchronic Document Construction</h4><table border="1" class="ednote" summary="Editorial note: Use Formalized ISD"><tr class="ednote-r1"><td align="left" valign="top"><b>Editorial note: Use Formalized ISD</b></td><td align="right" valign="top">2014-09-22</td></tr><tr class="ednote-r2"><td colspan="2" align="left" valign="top">Revise in order to take into account new formalization of ISD structure and semantics (Appendix C).</td></tr></table><p>For the purposes of performing presentation processing, the active time
 duration of a <a href="#terms-document-instance">document instance</a> 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 <a href="#terms-document-instance">document instance</a> is mapped from its original, source
@@ -5323,41 +5496,32 @@
 <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>6.2.6 ttp:frameRate</b></a>,
-<a href="#parameter-attribute-subFrameRate"><b>6.2.17 ttp:subFrameRate</b></a>,
-<a href="#parameter-attribute-tickRate"><b>6.2.18 ttp:tickRate</b></a>, and
-<a href="#parameter-attribute-timeBase"><b>6.2.19 ttp:timeBase</b></a> for further information on
+<a href="#parameter-attribute-subFrameRate"><b>6.2.19 ttp:subFrameRate</b></a>,
+<a href="#parameter-attribute-tickRate"><b>6.2.20 ttp:tickRate</b></a>, and
+<a href="#parameter-attribute-timeBase"><b>6.2.21 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
   | offset-time
-
 clock-time
   : hours ":" minutes ":" seconds ( fraction | ":" frames ( "." sub-frames )? )?
-
 offset-time
-  : time-count fraction? metric
-
+  : time-count fraction? metric?
 hours
   : <a href="#style-value-digit">&lt;digit&gt;</a> <a href="#style-value-digit">&lt;digit&gt;</a>
   | <a href="#style-value-digit">&lt;digit&gt;</a> <a href="#style-value-digit">&lt;digit&gt;</a> <a href="#style-value-digit">&lt;digit&gt;</a>+
-
 minutes | seconds
   : <a href="#style-value-digit">&lt;digit&gt;</a> <a href="#style-value-digit">&lt;digit&gt;</a>
-
 frames
   : <a href="#style-value-digit">&lt;digit&gt;</a> <a href="#style-value-digit">&lt;digit&gt;</a>
   | <a href="#style-value-digit">&lt;digit&gt;</a> <a href="#style-value-digit">&lt;digit&gt;</a> <a href="#style-value-digit">&lt;digit&gt;</a>+
-
 sub-frames
   : <a href="#style-value-digit">&lt;digit&gt;</a>+
-
 fraction
   : "." <a href="#style-value-digit">&lt;digit&gt;</a>+
-
 time-count
   : <a href="#style-value-digit">&lt;digit&gt;</a>+
-
 metric
   : "h"                 // hours
   | "m"                 // minutes
@@ -5381,9 +5545,11 @@
 <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>6.2.17 ttp:subFrameRate</b></a>.
+sub-frame rate determined by the <code>ttp:subFrameRate</code> parameter as defined by <a href="#parameter-attribute-subFrameRate"><b>6.2.19 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">
+when the <code>clock</code> time base applies.</p><p>If a &lt;timeExpression&gt; is expressed in terms of a
+<em>offset-time</em> and no <em>metric</em> is specified, then it is to be treated as
+if a metric of <code>s</code> (seconds) were specified.</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="#smil3">[SMIL 3.0]</a> apply to the interpretation of like-named timed elements and timing
 vocabulary defined by this specification, given the following
@@ -5655,24 +5821,18 @@
 <div class="exampleInner"><pre>
 &lt;keySplines&gt;
   : control [ lwsp? ";" lwsp? control ]*
-
 control
   : x1 comma? y1 comma? x2 comma? y2
-
 x1, x2, y1, y2
   : coordinate
-
 coordinate                                // 0 ≥ <em>value</em> ≥ 1
   : whole
   | whole "." fraction
   | "." fraction
-
 whole, fraction
   : <a href="#style-value-digit">&lt;digit&gt;</a>+
-
 comma
   : ","
-
 lwsp
   : ( ' ' | '\t' | '\n' | '\r' )+
 </pre></div>
@@ -5684,15 +5844,12 @@
 <div class="exampleInner"><pre>
 &lt;keyTimes&gt;
   : time [ lwsp? ";" lwsp? time ]*
-
 time                                // 0 ≥ <em>value</em> ≥ 1
   : whole
   | whole "." fraction
   | "." fraction
-
 whole, fraction
   : <a href="#style-value-digit">&lt;digit&gt;</a>+
-
 lwsp
   : ( ' ' | '\t' | '\n' | '\r' )+
 </pre></div>
@@ -5703,7 +5860,6 @@
 &lt;repeatCount&gt;
   : count
   | "indefinite"
-
 count:
   : <a href="#style-value-digit">&lt;digit&gt;</a>+                       // <em>value</em> &gt; 0
 </pre></div>
@@ -5721,7 +5877,7 @@
 <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 metadata that is expected to be commonly
-used in a <a href="#terms-document-instance">document instancea</a>:
+used in a <a href="#terms-document-instance">document instance</a>:
 </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 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
@@ -5861,7 +6017,6 @@
 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><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;
   &lt;head&gt;
     <span class="strong">&lt;ttm:agent xml:id="connery" type="person"&gt;</span>
@@ -5948,7 +6103,6 @@
 <div class="exampleInner"><pre>
 ttm:role
   role ( <em>S</em> role )*
-
 role
   : "action"
   | "caption"
@@ -5968,10 +6122,8 @@
   | "title"
   | "transcription"
   | extension-role
-
 extension-role
   : "x-" token-char+
-
 token-char
   : { XML NameChar }    // XML 1.1 Production [4a]
 </pre></div>
@@ -6009,9 +6161,165 @@
 of Timed Text Markup Language content as defined by this specification.
 In particular, the formal validity of TTML Content
 is defined by <a href="#conformance-content"><b>3.1 Content Conformance</b></a>.</p></div></div><div class="div1">
-<h2><a id="media-types-registration"></a>C Media Type Registration (Non-Normative)</h2><div class="note"><p class="prefix"><b>Note:</b></p><p>The information from this appendix has been removed since media type
-registration has already occurred. This section is retained in its empty form
-in order to prevent appendix renumbering.</p></div></div><div class="div1">
+<h2><a id="isd"></a>C Intermediate Synchronic Document Syntax</h2><p><em>This appendix is normative.</em></p><p>This appendix specifies the syntactic elements and structure of a TTML Intermediate Synchronic Document (ISD) Sequence and its
+constituent TTML Intermediate Synchronic Document (ISD) instances. An ISD instance may be represented as a standalone document instance or
+in a collection represented as an ISD Sequence instance.</p><p>All ISD related vocabulary is defined in the TTML ISD Namespace, defined here as <code>http://www.w3.org/ns/ttml#isd</code>,
+where the recommended prefix is <code>isd</code>.</p><p>A TTML <a href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</a>, in short, an <em>ISD</em> or <em>ISD instance</em>,
+represents a discrete, temporally non-overlapping interval, an <em>ISD interval</em>,
+of a source TTML document where, except for non-discrete animation, all content, styling, and layout information remains static within that interval.
+In particular, the timing hierarchy of a TTML document is flattened and then sub-divided into temporally non-overlapping intervals, where each such
+interval defines a static view of the source TTML document within that interval, and where that static view is represented as an ISD instance.
+A concrete, standalone instance of a TTML
+<a href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</a> must specify an
+<a href="#isd-vocabulary-isd"><code>isd:isd</code></a> element as its root document element. When an instance of a
+<a href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</a> is included in a
+<a href="#terms-intermediate-synchronic-document-sequence">Intermediate Synchronic Document Sequence</a> instance, then the ISD instance is represented
+by an <a href="#isd-vocabulary-isd"><code>isd:isd</code></a> child element of the root 
+<a href="#isd-vocabulary-sequence"><code>isd:sequence</code></a> element.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>An ISD instance may contain one or more animate elements that denote continuous animation within the associated interval. Continuously animated styles are sub-divided across
+ISD interval boundaries such that their step-wise concatenation expresses an equivalent continuous animation over any intersecting ISD interval(s).</p></div><p>A TTML <a href="#terms-intermediate-synchronic-document-sequence">Intermediate Synchronic Document Sequence</a> represents a collection
+of temporally non-overlapping <a href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</a> instances ordered according
+to their begin times. A concrete instance of a TTML
+<a href="#terms-intermediate-synchronic-document-sequence">Intermediate Synchronic Document Sequence</a> must specify an
+<a href="#isd-vocabulary-sequence"><code>isd:sequence</code></a> element as its root document element.</p><div class="div2">
+<h3><a id="isd-vocabulary"></a>C.1 ISD Vocabulary</h3><div class="div3">
+<h4><a id="isd-vocabulary-sequence"></a>C.1.1 isd:sequence</h4><p>The <code>isd:sequence</code> element serves as the root document element of an <a href="#terms-intermediate-synchronic-document-sequence">Intermediate
+Synchronic Document Sequence</a>  document.</p><p>The <code>isd:sequence</code> element accepts as its children zero or more elements in the
+<a href="#element-vocab-group-metadata"><code>Metadata.class</code></a> element group,
+followed by zero or one <a href="#parameter-vocabulary-profile"><code>ttp:profile</code></a> element,
+followed by zero or more <a href="#isd-vocabulary-isd"><code>isd:isd</code></a> elements.</p><p>Child <code>isd:isd</code> elements must be ordered in accordance to the media time equivalent of their
+begin time; furthermore, the temporal intervals of any two child <a href="#isd-vocabulary-isd"><code>isd:isd</code></a> elements must not overlap (in time).</p><a id="elt-syntax-isd-sequence"></a><table class="syntax"><caption>XML Representation – Element Information Item: isd:sequence</caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+&lt;isd:sequence
+  size = xsd:nonNegativeInteger
+  version = xsd:positiveInteger
+  <a href="#content-attribute-lang"><span class="reqattr">xml:lang</span></a> = string
+  {<em>any attribute in the <a href="#isd-parameter-attribute-set">ISD Parameter Attribute Set</a></em>}&gt;
+  {<em>any attribute not in default or any TT namespace</em>}&gt;
+  <em>Content:</em> <a href="#element-vocab-group-metadata">Metadata.class</a>*, <a href="#parameter-vocabulary-profile">ttp:profile</a>?, <a href="#isd-vocabulary-isd">isd:isd</a>*
+&lt;/isd:sequence&gt;
+</pre></div>
+</td></tr></tbody></table><p>If the <code>size</code> attribute is specified, then it must be a non-negative integer corresponding to the number of
+<a href="#isd-vocabulary-isd"><code>isd:isd</code></a> child elements.
+If not specified, then the size must be considered to be <em>indefinite</em>, unless and until the
+<a href="#isd-vocabulary-sequence"><code>isd:sequence</code></a> element is terminated, in which case the size
+may be determined by inspection.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The <code>size</code> attribute would normally be omitted in the case of real time captioning.</p></div><p>If the <code>version</code> attribute is specified, then it must be a positive integer corresponding to the version of this
+<a href="#terms-intermediate-synchronic-document-syntax">Intermediate Synchronic Document Syntax</a> specification used in authoring
+the ISD sequence document. If specified, the numeric value must be greater than or equal to two (2). If not specified, then the version must be
+consider to be equal to two (2). The version associated with this
+<a href="#terms-intermediate-synchronic-document-sequence-syntax">Intermediate Synchronic Document Sequence Syntax</a> specification is two (2).</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The ISD abstraction referred to or implied by <a href="#ttml1">[TTML1]</a> §9.3.2 was not concretely defined by that specification. Here we reserve version one (1)
+for informal discussion of that earlier abstraction and its various (non-standardized) realizations.</p></div><p>An <a href="#content-attribute-lang"><code>xml:lang</code></a> attribute must be specified on the
+<a href="#isd-vocabulary-sequence"><code>isd:sequence</code></a> element.
+If its value is empty, it signifies that there is no default language that applies
+to the content within the <a href="#terms-intermediate-synchronic-document-sequence">Intermediate Synchronic Document Sequence</a>. Otherwise,
+the specified value denotes the default language that applies to each constituent
+<a href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</a>.</p><p>One or more parameter properties may be specified from the restricted parameter attribute set enumerated in <a href="#isd-parameter-attribute-set"><b>C.2 ISD Parameter Attribute Set</b></a>.
+If specified, then they apply globally to each constituent <a href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</a>.</p><p>If a child <a href="#parameter-vocabulary-profile"><code>ttp:profile</code></a> element is present,
+then that <a href="#parameter-vocabulary-profile"><code>ttp:profile</code></a> element must satisfy the following constraints:</p><ul><li><p>no <code>combine</code> attribute is specified;</p></li><li><p>no <code>designator</code> attribute is specified;</p></li><li><p>no <code>type</code> attribute is specified;</p></li><li><p>no <code>use</code> attribute is specified;</p></li><li><p>no descendant element is a <code>ttp:profile</code> element;</p></li><li><p>no descendant <code>ttp:feature</code> element specifies a <code>value</code> attribute with the value <code>prohibited</code>;</p></li><li><p>no descendant <code>ttp:extension</code> element specifies a <code>value</code> attribute with the value <code>prohibited</code>.</p></li></ul><p>Furthermore, such a child <a href="#parameter-vocabulary-profile"><code>ttp:profile</code></a> element must specify a profile that is equivalent to the combined
+<a href="#terms-processor-profile">processor profile</a> of the source TTML document having fetched all externally referenced profile documents.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The intent of permitting a single <a href="#parameter-vocabulary-profile"><code>ttp:profile</code></a> to be specified in an
+<a href="#isd-vocabulary-sequence"><code>isd:sequence</code></a> is to provide a simplified mechanism to declare
+processor profile requirements that must be met in order to process the document (in the absence of an end-user override).</p></div></div><div class="div3">
+<h4><a id="isd-vocabulary-isd"></a>C.1.2 isd:isd</h4><p>The <code>isd:isd</code> element serves either as (1) the root document element of a standalone <a href="#terms-intermediate-synchronic-document">Intermediate
+Synchronic Document</a> or (2) as a child of an <a href="#isd-vocabulary-sequence"><code>isd:sequence</code></a> element of a
+<a href="#terms-intermediate-synchronic-document-sequence">Intermediate Synchronic Document Sequence</a> document.</p><p>The <code>isd:isd</code> element accepts as its children zero or more elements in the
+<a href="#element-vocab-group-metadata"><code>Metadata.class</code></a> element group,
+followed by zero or one <a href="#parameter-vocabulary-profile"><code>ttp:profile</code></a> element,
+followed by zero or more <a href="#isd-vocabulary-css"><code>isd:css</code></a> elements,
+followed by zero or more <a href="#isd-vocabulary-region"><code>isd:region</code></a> elements.</p><a id="elt-syntax-isd"></a><table class="syntax"><caption>XML Representation – Element Information Item: isd:isd</caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+&lt;isd:isd
+  <a href="#timing-attribute-begin"><span class="reqattr">begin</span></a> = <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>
+  <a href="#timing-attribute-end"><span class="reqattr">end</span></a> = <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>
+  version = xsd:positiveInteger
+  <a href="#content-attribute-lang">xml:lang</a> = string
+  {<em>any attribute in the <a href="#isd-parameter-attribute-set">ISD Parameter Attribute Set</a></em>}&gt;
+  {<em>any attribute not in default or any TT namespace</em>}&gt;
+  <em>Content:</em> <a href="#element-vocab-group-metadata">Metadata.class</a>*, <a href="#parameter-vocabulary-profile">ttp:profile</a>?, <a href="#isd-vocabulary-css">isd:css</a>*, <a href="#isd-vocabulary-region">isd:region</a>*
+&lt;/isd:isd&gt;
+</pre></div>
+</td></tr></tbody></table><p>A <code>begin</code> attribute must be specified, the value of which must take the <em>offset-time</em> form of
+a <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>, and, further, is restricted to use a metric of
+<code>s</code> (seconds),
+<code>f</code> (frames),
+<code>t</code> (ticks), or may omit the metric, in which case <code>s</code> seconds is implied. This
+begin time is expressed as an offset from the begin time of the <a href="#terms-root-temporal-extent">root temporal extent</a>
+of the source TTML document from which this <a href="#isd-vocabulary-isd"><code>isd:isd</code></a> element was derived.</p><p>An <code>end</code> attribute must be similarlly specified, where the same constraints apply.
+This end time is expressed as an offset from the begin time of the <a href="#terms-root-temporal-extent">root temporal extent</a>
+of the source TTML document from which this <a href="#isd-vocabulary-isd"><code>isd:isd</code></a> element was derived.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>Expressed in the terminology of <a href="#smil3">[SMIL 3.0]</a>, the values of these <code>begin</code> and <code>end</code> attributes
+correspond to the resolved begin and end times of the <em>active duration</em> with respect to the <em>document begin</em>.</p></div><p>An <a href="#content-attribute-lang"><code>xml:lang</code></a> attribute must be specified on the
+<a href="#isd-vocabulary-isd"><code>isd:isd</code></a> element if it is a standalone <a href="#terms-intermediate-synchronic-document">Intermediate
+Synchronic Document</a> document; otherwise, it may be specified, and should be specified if the default language of the 
+<a href="#isd-vocabulary-sequence"><code>isd:isd</code></a> element differs from the default language of its
+parent <a href="#isd-vocabulary-sequence"><code>isd:sequence</code></a> element.
+If its value is empty, it signifies that there is no default language that applies
+to the content within the <a href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</a>. Otherwise,
+the specified value denotes the default language that applies.</p><p>The <code>version</code> attribute follows the syntax and semantics of the same named attribute on the
+<a href="#isd-vocabulary-sequence"><code>isd:sequence</code></a> element type. The <code>version</code>
+attribute must not be specified on an <a href="#isd-vocabulary-isd">isd:isd</a> element that is not
+a root document element, i.e., is a child element of an <a href="#isd-vocabulary-sequence">isd:sequence</a> element.</p><p>A child <a href="#parameter-vocabulary-profile"><code>ttp:profile</code></a> element may be present if the
+<a href="#isd-vocabulary-isd"><code>isd:isd</code></a> element is a standalone <a href="#terms-intermediate-synchronic-document">Intermediate
+Synchronic Document</a> document, in which case the same constraints and semantics apply as specified in <a href="#isd-vocabulary-sequence"><b>C.1.1 isd:sequence</b></a>;
+otherwise, if not a standalone document, a child <a href="#parameter-vocabulary-profile"><code>ttp:profile</code></a> element must not be present.</p></div><div class="div3">
+<h4><a id="isd-vocabulary-css"></a>C.1.3 isd:css</h4><p>The <code>isd:css</code> element is used to represent a unique computed style set of some collection of elements
+that share the same set of computed styles. In particular, for each
+element <em>E</em> in the source TTML document which is selected and copied into a
+<a href="#isd-vocabulary-region"><code>isd:region</code></a> element of a given
+<a href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</a>, the computed style
+set of <em>E</em>, <em>CSS(E)</em>, is determined, and, if that <em>CSS(E)</em> is not already specified
+by an existing <code>isd:css</code> element, then it is assigned a unique identifier and instantiated as a new
+<code>isd:css</code> element.</p><p>The <code>isd:css</code> element accepts as its children zero or more elements in the
+<a href="#element-vocab-group-metadata"><code>Metadata.class</code></a> element group.</p><a id="elt-syntax-isd-style"></a><table class="syntax"><caption>XML Representation – Element Information Item: isd:css</caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+&lt;isd:css
+  <a href="#content-attribute-id"><span class="reqattr">xml:id</span></a> = ID
+  {<em>any attribute in TT Style namespace</em>}
+  {<em>any attribute not in default or any TT namespace</em>}&gt;
+  <em>Content:</em> <a href="#element-vocab-group-metadata">Metadata.class</a>*
+&lt;/isd:css&gt;
+</pre></div>
+</td></tr></tbody></table><p>For each arbitrary pair of <code>isd:css</code> child elements of an
+<a href="#isd-vocabulary-isd"><code>isd:isd</code></a> element,
+<em>S1</em> and <em>S2</em>, the set of specified styles of <em>S1</em> must
+not be the same as the set of specified styles of <em>S2</em>. For the purpose of comparing two
+sets of specified styles, the styles must be placed into a canonical order and then compared item
+by item for value equality, where the canonical order is in accordance to the qualified attribute name
+order, where each qualified name consists of a tuple <code>&lt;namespace URL, local name&gt;</code>,
+and such tuples are compared component-wise by case-sensitive lexical string order.</p></div><div class="div3">
+<h4><a id="isd-vocabulary-region"></a>C.1.4 isd:region</h4><p>The <code>isd:region</code> element is used to represent a layout and presentation region
+and the content selected into that region, where that content takes the form of a
+<a href="#document-structure-vocabulary-body">body</a> element and its descendant TTML content elements.</p><p>The <code>isd:region</code> element accepts as its children zero or more elements in the
+<a href="#element-vocab-group-metadata"><code>Metadata.class</code></a> element group,
+followed by zero or more <a href="#animation-vocabulary-animate"><code>animate</code></a> elements,
+followed by exactly one <a href="#document-structure-vocabulary-body"><code>body</code></a> element.</p><a id="elt-syntax-isd-region"></a><table class="syntax"><caption>XML Representation – Element Information Item: isd:region</caption><tbody><tr><td>
+<div class="exampleInner"><pre>
+&lt;isd:region
+  <a href="#style-attribute-style">style</a> = IDREF
+  <a href="#metadata-attribute-role">ttm:role</a> = string
+  <a href="#content-attribute-id"><span class="reqattr">xml:id</span></a> = ID
+  {<em>any attribute not in default or any TT namespace</em>}&gt;
+  <em>Content:</em> <a href="#element-vocab-group-metadata">Metadata.class</a>*, <a href="#animation-vocabulary-animate">animate</a>*, <a href="#document-structure-vocabulary-body">body</a>
+&lt;/isd:region&gt;
+</pre></div>
+</td></tr></tbody></table><p>If the computed style set of the region represented by the <code>isd:region</code> element is not the
+set of initial style values that apply to <a href="#layout-vocabulary-region"><code>region</code></a>, then a
+<code>style</code> attribute must be specified which references an <a href="#isd-vocabulary-css"><code>isd:css</code></a> element that specifies the
+region's computed style set.</p><p>The following constraints apply to the <a href="#document-structure-vocabulary-body"><code>body</code></a> element
+and its descendant elements:</p><ul><li><p>no <code>animate</code> attribute is specified;</p></li><li><p>no <code>begin</code> attribute is specified;</p></li><li><p>no <code>dur</code> attribute is specified;</p></li><li><p>no <code>end</code> attribute is specified;</p></li><li><p>no <code>region</code> attribute is specified;</p></li><li><p>no <code>timeContainer</code> attribute is specified;</p></li><li><p>no attribute in the TT Style namespace is specified;</p></li><li><p>no <a href="#animation-vocabulary-set">set</a> element is present;</p></li><li><p>no significant text node, i.e., text node in a #PCDATA context, is not contained in a 
+<a href="#content-vocabulary-span"><code>span</code></a> element that contains no other child.</p></li></ul><p>In addition, for the <a href="#document-structure-vocabulary-body"><code>body</code></a> element <em>B</em> and
+each of its descendant content elements <em>C</em>, if the computed style set of <em>B</em> or each <em>C</em> is
+not equal to the computed style set of its parent element, then that element, <em>B</em> or <em>C</em>, must specify a <code>style</code>
+attribute that references an <a href="#isd-vocabulary-css"><code>isd:css</code></a> element that specifies the
+element's computed style set.</p></div></div><div class="div2">
+<h3><a id="isd-parameter-attribute-set"></a>C.2 ISD Parameter Attribute Set</h3><p>The following subset of the defined <a href="#attribute-vocab-group-parameters">Parameter Attributes</a>
+are available for use with an
+<a href="#isd-vocabulary-structure"><code>isd:structure</code></a> or
+<a href="#isd-vocabulary-isd"><code>isd:isd</code></a> element as described above:</p><ul><li><p><a href="#parameter-attribute-cellResolution">ttp:cellResolution</a></p></li><li><p><a href="#parameter-attribute-frameRate">ttp:frameRate</a></p></li><li><p><a href="#parameter-attribute-frameRateMultiplier">ttp:frameRateMultipler</a></p></li><li><p><a href="#parameter-attribute-mediaOffset">ttp:mediaOffset</a></p></li><li><p><a href="#parameter-attribute-pixelAspectRatio">ttp:pixelAspectRatio</a></p></li><li><p><a href="#parameter-attribute-subFrameRate">ttp:subFrameRate</a></p></li><li><p><a href="#parameter-attribute-tickRate">ttp:tickRate</a></p></li></ul></div><div class="div2">
+<h3><a id="isd-interchange"></a>C.3 ISD Interchange</h3><p>A concrete document instance that employs the <a href="#isd">Intermediate Synchronic Document Syntax</a> must be
+encoded as a well-formed <a href="#xml10">[XML 1.0]</a> document using the UTF-8 character encoding. Furthermore, such a document must specify
+an <a href="#isd-vocabulary-sequence"><code>isd:sequence</code></a> element or
+an <a href="#isd-vocabulary-isd"><code>isd:isd</code></a> element as the root document element.</p><p>When a resource consisting of a concrete ISD Sequence or ISD instance is interchanged and a media type is used to identify the content type
+of that resource, then the media type <code>application/ttml+xml</code> should be used, about which see <a href="#ttml1">[TTML1]</a> Appendix C.
+If this media type is used, the optional <code>profile</code> parameter must not be specified, or, if specified, must be ignored by a processor.</p></div><div class="div2">
+<h3><a id="isd-examples"></a>C.4 ISD Examples</h3><p><em>This sub-section is non-normative.</em></p><table border="1" class="ednote" summary="Editorial note: Add ISD Examples"><tr class="ednote-r1"><td align="left" valign="top"><b>Editorial note: Add ISD Examples</b></td><td align="right" valign="top">2014-09-22</td></tr><tr class="ednote-r2"><td colspan="2" align="left" valign="top">Add worked out examples of ISD Sequence and ISD document instances.</td></tr></table></div></div><div class="div1">
 <h2><a id="features"></a>D Features</h2><p><em>This appendix is normative.</em></p><p>This appendix specifies (1) a set of feature designations, each of which
 labels one or more syntactic and/or semantic features defined by this
 specification, and (2) for each designated feature, whether the feature is mandatory
@@ -6024,13 +6332,10 @@
 form:</p><div class="exampleInner"><pre>
 feature-designation
   : feature-namespace designation
-
 feature-namespace
   : <em>TT Feature Namespace</em>                    // http://www.w3.org/ns/ttml/feature/
-
 designation
   : "#" token-char+
-
 token-char
   : { XML NameChar }                        // XML 1.1 Production [4a]
 </pre></div><p>All values of <code>feature-designation</code> not defined by this specification are reserved
@@ -7000,14 +7305,11 @@
 form:</p><div class="exampleInner"><pre>
 extension-designation
   : extension-namespace designation
-
 extension-namespace
   : <em>TT Extension Namespace</em>                  // http://www.w3.org/ns/ttml/extension/
   | <em>Other Extension Namespace</em>               // expressed as an absolute URI
-
 designation
   : "#" token-char+
-
 token-char
   : { XML NameChar }                        // XML 1.1 Production [4a]
 </pre></div><p>If the extension namespace of an extension designation is the TT
@@ -7436,6 +7738,10 @@
 <a href="http://www.w3.org/TR/2011/REC-css3-color-20110607/"><cite>CSS Color
 Module Level 3</cite></a>, W3C Recommendation, 07 June 2011. (See
 <a href="http://www.w3.org/TR/2011/REC-css3-color-20110607/">http://www.w3.org/TR/2011/REC-css3-color-20110607/</a>.)
+</dd><dt class="label"><a id="cssruby"></a>CSS Ruby</dt><dd>Elika Etemad and Koji Ishii,
+<a href="http://dev.w3.org/csswg/css-ruby-1/"><cite>CSS Ruby Layout Module Level 1</cite></a>
+W3C Editor's Draft.
+(See <a href="http://dev.w3.org/csswg/css-ruby-1/">http://dev.w3.org/csswg/css-ruby-1//</a>.)
 </dd><dt class="label"><a id="gps"></a>GPS</dt><dd>
 <a href="http://tycho.usno.navy.mil/gpsinfo.html"><cite>Global
 Positioning System</cite></a>, US Naval Observatory.
@@ -7450,6 +7756,10 @@
 <a href="http://www.iso.org/"><cite>Information technology – Document
 Schema Definition Language (DSDL) – Part 2: Regular-grammar-based validation – RELAX NG</cite></a>,
 International Organization for Standardization (ISO).
+</dd><dt class="label"><a id="ruby"></a>Ruby</dt><dd>Masayasu Ishikawa et al.,
+<a href="http://www.w3.org/TR/2001/REC-ruby-20010531/"><cite>Ruby Annotation</cite></a>
+W3C Recommendation, 31 May 2001.
+(See <a href="http://www.w3.org/TR/2001/REC-ruby-20010531/">http://www.w3.org/TR/2001/REC-ruby-20010531/</a>.)
 </dd><dt class="label"><a id="smil3"></a>SMIL 3.0</dt><dd>Dick Bultermann, et al.,
 <a href="http://www.w3.org/TR/2008/REC-SMIL3-20081201/"><cite>Synchronized
 Multimedia Integration Language (SMIL 3.0)</cite></a>,
@@ -7551,11 +7861,19 @@
 </dd><dt class="label"><a id="dcmes"></a>DCMES 1.1</dt><dd>Dublin Core Metadata Initiative,
 <a href="http://dublincore.org/documents/dces/"><cite>Dublin Core Metadata Element Set, Version 1.1: Reference Description</cite></a>. (See
 <a href="http://dublincore.org/documents/dces/">http://dublincore.org/documents/dces/</a>.)
+</dd><dt class="label"><a id="jlreq"></a>JLREQ</dt><dd>Richard Ishida et al.,
+<a href="http://www.w3.org/TR/2012/NOTE-jlreq-20120403/"><cite>Requirements for Japanese Text Layout</cite></a>
+W3C Working Group Note, 3 April 2012.
+(See <a href="http://www.w3.org/TR/2012/NOTE-jlreq-20120403/">http://www.w3.org/TR/2012/NOTE-jlreq-20120403/</a>.)
 </dd><dt class="label"><a id="mpeg7-5"></a>MPEG7-5</dt><dd>
 ISO/IEC 15938-5,
 <a href="http://www.iso.org/"><cite>Information technology – Multimedia content description
 interface – Part 5: Multimedia description schemes</cite></a>,
 International Organization for Standardization (ISO).
+</dd><dt class="label"><a id="nsoriginal"></a>NSOriginal</dt><dd>Tim Bray, et al.
+<a href="http://www.w3.org/TR/1999/REC-xml-names-19990114/"><cite>Namespaces
+in XML</cite></a>, W3C Recommendation, 14 January 1999. (See
+<a href="http://www.w3.org/TR/1999/REC-xml-names-19990114/">http://www.w3.org/TR/1999/REC-xml-names-19990114/</a>.)
 </dd><dt class="label"><a id="nsstate"></a>NSState</dt><dd>Norman Walsh, Ed.,
 <a href="http://www.w3.org/2001/tag/doc/namespaceState-2006-01-09.html"><cite>The Disposition
 of Names in an XML Namespace</cite></a>, TAG Finding, 9 January 2006. (See
@@ -7604,7 +7922,7 @@
 <h2><a id="derivation"></a>J Vocabulary Derivation (Non-Normative)</h2><p>This appendix provides information about the derivation of TTML
 vocabulary, separately describing derivation of elements and
 attributes.</p><div class="div2">
-<h3><a id="d3e25233"></a>J.1 Element Derivation</h3><p>The first column of <a href="#element-vocab-derivation-table"><b>Table J-1 – Elements</b></a>
+<h3><a id="d3e27291"></a>J.1 Element Derivation</h3><p>The first column of <a href="#element-vocab-derivation-table"><b>Table J-1 – Elements</b></a>
 specifies a TTML element vocabulary item; the second column specifies the
 syntactic and/or semantic model on which the vocabulary item is based;
 the third column specifies the reference that defines
@@ -7661,7 +7979,7 @@
 and <code>@version</code> on the <code>svg:svg</code> element.</p></li><li><p>Conceptually derived from existing <code>tt:layout</code> element,
 which is a generic container for layout specifications, but for use
 in defining animation specifications that apply to targeted elements.</p></li></ol></div></div><div class="div2">
-<h3><a id="d3e25750"></a>J.2 Attribute Derivation</h3><p>The first column of <a href="#attribute-vocab-derivation-table"><b>Table J-2 – Attributes</b></a>
+<h3><a id="d3e27808"></a>J.2 Attribute Derivation</h3><p>The first column of <a href="#attribute-vocab-derivation-table"><b>Table J-2 – Attributes</b></a>
 specifies a TTML attribute vocabulary item; the second column specifies the
 syntactic and/or semantic model on which the vocabulary item is based;
 the third column specifies the reference that defines
@@ -7753,9 +8071,9 @@
 <h2><a id="qa"></a>K QA Framework Compliance (Non-Normative)</h2><p>This appendix specifies the compliance of this specification with the
 requirements and guidelines defined by <a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/">QA
 Framework Specifications Guidelines</a>&nbsp;<a href="#qaf-sg">[QAF SG]</a>.</p><div class="div2">
-<h3><a id="d3e26743"></a>K.1 Requirements</h3><a id="qa-framework-requirements-table"></a><table class="common"><caption>Table K-1 – QA Framework Requirements Checklist</caption><col width="76%" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><tbody><tr><td><span class="strong">Requirement</span></td><td><span class="strong">YES</span></td><td><span class="strong">NO</span></td><td><span class="strong">N/A</span></td><td><span class="strong">Notes</span></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#include-conformance-clause-principle">Requirement 01: Include a conformance
+<h3><a id="d3e28801"></a>K.1 Requirements</h3><a id="qa-framework-requirements-table"></a><table class="common"><caption>Table K-1 – QA Framework Requirements Checklist</caption><col width="76%" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><tbody><tr><td><span class="strong">Requirement</span></td><td><span class="strong">YES</span></td><td><span class="strong">NO</span></td><td><span class="strong">N/A</span></td><td><span class="strong">Notes</span></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#include-conformance-clause-principle">Requirement 01: Include a conformance
 clause</a></td><td><a href="#conformance">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#define-scope-principle">Requirement 02: Define the scope.</a></td><td><a href="#intro">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#implement-principle">Requirement 03: Identify who or what will implement the specification.</a></td><td><a href="#conformance">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#ref-norm-principle">Requirement 04: Make a list of normative references.</a></td><td><a href="#references">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#define-terms-principle">Requirement 05: Define the terms used in the normative parts of the specification.</a></td><td><a href="#definitions">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#conf-label-principle">Requirement 06: Create conformance labels for each part of the conformance model.</a></td><td><a href="#conformance">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#consistent-style-principle">Requirement 07: Use a consistent style for conformance requirements and explain how to distinguish them.</a></td><td><a href="#conventions">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#req-opt-conf-principle">Requirement 08: Indicate which conformance requirements are mandatory, which are recommended, and which are optional.</a></td><td><a href="#conventions">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#subdivide-mandatory-principle">Requirement 09: If the technology is subdivided, then indicate which subdivisions are mandatory for conformance.</a></td><td><a href="#conformance">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#subdiv-constraints-principle">Requirement 10: If the technology is subdivided, then address subdivision constraints.</a></td><td><a href="#conformance">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#likehood-extension-principle">Requirement 11: Address Extensibility.</a></td><td><a href="#doctypes">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#deprecated-feature-principle">Requirement 12: Identify deprecated features.</a></td><td></td><td></td><td>N/A</td><td>1</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#degree-support-principle">Requirement 13: Define how each class of product handles each deprecated feature.</a></td><td></td><td></td><td>N/A</td><td>1</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><ol class="enumar"><li><p>No feature is deprecated by this version of this specification.</p></li></ol></div></div><div class="div2">
-<h3><a id="d3e26907"></a>K.2 Guidelines</h3><a id="qa-framework-guidelines-table"></a><table class="common"><caption>Table K-2 – QA Framework Guidelines Checklist</caption><col width="76%" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><tbody><tr><td><span class="strong">Guideline</span></td><td><span class="strong">YES</span></td><td><span class="strong">NO</span></td><td><span class="strong">N/A</span></td><td><span class="strong">Notes</span></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#conformance-model-gp">Good Practice 01: Define the specification's conformance model in the conformance clause.</a></td><td><a href="#conformance">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#norm-informative-gp">Good Practice 02: Specify in the conformance clause how to distinguish normative from informative content.</a></td><td><a href="#conventions">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#conformance-claim-gp">Good Practice 03: Provide the wording for conformance claims.</a></td><td><a href="#claims">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#ics-gp">Good Practice 04: Provide an Implementation Conformance Statement Pro Forma.</a></td><td></td><td>NO</td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#ics-claim-gp">Good Practice 05: Require an Implementation Conformance Statement as part of valid conformance claims.</a></td><td><a href="#claims">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#use-example-gp">Good Practice 06: Provide examples, use cases, and graphics.</a></td><td><a href="#example">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#write-sample-gp">Good Practice 07: Write sample code or tests.</a></td><td>YES</td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#ref-define-practice">Good Practice 08: When imposing requirements by normative references, address conformance dependencies.</a></td><td><a href="#references">YES</a></td><td></td><td></td><td>1</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#define-terms-inline-gp">Good Practice 09: Define unfamiliar terms in-line and consolidate the definitions in a glossary section.</a></td><td><a href="#definitions">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#reuse-terms-gp">Good Practice 10: Use terms already defined without changing their definition.</a></td><td><a href="#definitions">YES</a></td><td></td><td></td><td>2</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#formal-language-gp">Good Practice 11: Use formal languages when possible.</a></td><td><a href="#schemas">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#write-assertion-gp">Good Practice 12: Write Test Assertions.</a></td><td></td><td>NO</td><td></td><td>3</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#subdivide-foster-gp">Good Practice 13: Create subdivisions of the technology when warranted.</a></td><td><a href="#conformance">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#rules-profiles-gp">Good Practice 14: If the technology is profiled, define rules for creating new profiles.</a></td><td><a href="#vocabulary-profiles">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#need-option-gp">Good Practice 15:Use optional features as warranted.</a></td><td>YES</td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#label-options-gp">Good Practice 16: Clearly identify optional features.</a></td><td>YES</td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#constraints-gp">Good Practice 17: Indicate any limitations or constraints on optional features.</a></td><td>YES</td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#extensions-prohibited-gp">Good Practice 18: If extensibility is allowed, define an extension mechanism.</a></td><td><a href="#extension-vocabulary-overview">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#breaking-conformance-gp">Good Practice 19: Warn extension creators to create extensions that do not interfere with conformance.</a></td><td><a href="#extension-vocabulary-overview">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#define-error-gp">Good Practice 20: Define error-handling for unknown extensions.</a></td><td><a href="#conformance-processor">YES</a></td><td></td><td></td><td>4</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#workaround-gp">Good Practice 21: Explain how to avoid using a deprecated feature.</a></td><td></td><td></td><td>N/A</td><td>5</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#obsolete-gp">Good Practice 22: Identify obsolete features.</a></td><td></td><td></td><td>N/A</td><td>5</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#error-handling-gp">Good Practice 23: Define an error handling mechanism.</a></td><td><a href="#reduced-infoset">YES</a></td><td></td><td></td><td></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><ol class="enumar"><li><p>When making normative references to external specifications,
+<h3><a id="d3e28965"></a>K.2 Guidelines</h3><a id="qa-framework-guidelines-table"></a><table class="common"><caption>Table K-2 – QA Framework Guidelines Checklist</caption><col width="76%" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><col width="6%" align="center" span="1"><tbody><tr><td><span class="strong">Guideline</span></td><td><span class="strong">YES</span></td><td><span class="strong">NO</span></td><td><span class="strong">N/A</span></td><td><span class="strong">Notes</span></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#conformance-model-gp">Good Practice 01: Define the specification's conformance model in the conformance clause.</a></td><td><a href="#conformance">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#norm-informative-gp">Good Practice 02: Specify in the conformance clause how to distinguish normative from informative content.</a></td><td><a href="#conventions">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#conformance-claim-gp">Good Practice 03: Provide the wording for conformance claims.</a></td><td><a href="#claims">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#ics-gp">Good Practice 04: Provide an Implementation Conformance Statement Pro Forma.</a></td><td></td><td>NO</td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#ics-claim-gp">Good Practice 05: Require an Implementation Conformance Statement as part of valid conformance claims.</a></td><td><a href="#claims">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#use-example-gp">Good Practice 06: Provide examples, use cases, and graphics.</a></td><td><a href="#example">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#write-sample-gp">Good Practice 07: Write sample code or tests.</a></td><td>YES</td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#ref-define-practice">Good Practice 08: When imposing requirements by normative references, address conformance dependencies.</a></td><td><a href="#references">YES</a></td><td></td><td></td><td>1</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#define-terms-inline-gp">Good Practice 09: Define unfamiliar terms in-line and consolidate the definitions in a glossary section.</a></td><td><a href="#definitions">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#reuse-terms-gp">Good Practice 10: Use terms already defined without changing their definition.</a></td><td><a href="#definitions">YES</a></td><td></td><td></td><td>2</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#formal-language-gp">Good Practice 11: Use formal languages when possible.</a></td><td><a href="#schemas">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#write-assertion-gp">Good Practice 12: Write Test Assertions.</a></td><td></td><td>NO</td><td></td><td>3</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#subdivide-foster-gp">Good Practice 13: Create subdivisions of the technology when warranted.</a></td><td><a href="#conformance">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#rules-profiles-gp">Good Practice 14: If the technology is profiled, define rules for creating new profiles.</a></td><td><a href="#vocabulary-profiles">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#need-option-gp">Good Practice 15:Use optional features as warranted.</a></td><td>YES</td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#label-options-gp">Good Practice 16: Clearly identify optional features.</a></td><td>YES</td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#constraints-gp">Good Practice 17: Indicate any limitations or constraints on optional features.</a></td><td>YES</td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#extensions-prohibited-gp">Good Practice 18: If extensibility is allowed, define an extension mechanism.</a></td><td><a href="#extension-vocabulary-overview">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#breaking-conformance-gp">Good Practice 19: Warn extension creators to create extensions that do not interfere with conformance.</a></td><td><a href="#extension-vocabulary-overview">YES</a></td><td></td><td></td><td></td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#define-error-gp">Good Practice 20: Define error-handling for unknown extensions.</a></td><td><a href="#conformance-processor">YES</a></td><td></td><td></td><td>4</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#workaround-gp">Good Practice 21: Explain how to avoid using a deprecated feature.</a></td><td></td><td></td><td>N/A</td><td>5</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#obsolete-gp">Good Practice 22: Identify obsolete features.</a></td><td></td><td></td><td>N/A</td><td>5</td></tr><tr><td><a href="http://www.w3.org/TR/2005/REC-qaframe-spec-20050817/#error-handling-gp">Good Practice 23: Define an error handling mechanism.</a></td><td><a href="#reduced-infoset">YES</a></td><td></td><td></td><td></td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><ol class="enumar"><li><p>When making normative references to external specifications,
 specific clauses or sections are cited.</p></li><li><p>See also <a href="#derivation"><b>J Vocabulary Derivation</b></a>.</p></li><li><p>Test assertions and test suites will be provided prior to entering
 Proposed Recommendation (PR) phase.</p></li><li><p>See criterion #3 in <a href="#conformance-processor"><b>3.2 Processor Conformance</b></a> and definition of
 TTML <a href="#doctypes">Abstract Document Instance</a>.</p></li><li><p>No feature is deprecated or obsoleted by this version of this specification.</p></li></ol></div></div></div><div class="div1">
@@ -7900,8 +8218,9 @@
 <br><br>
 and <code>tickRate</code> is the computed value of the <code>ttp:tickRate</code> parameter;
 <br></p></blockquote>
-</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>If the computed <code>frameRateMultipler</code> ratio is not integral, then <code>effectiveFrameRate</code> will be a non-integral rational.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>The above formalisms assumes that the <a href="#terms-root-temporal-extent">root temporal extent</a> corresponds with the beginning of a related media object. If
-this assumption doesn't hold, then an additional offset that accounts for the difference may be introduced when computing media time <code>M</code>.</p></div></div><div class="div2">
+</td></tr></tbody></table><div class="note"><p class="prefix"><b>Note:</b></p><p>If the computed <code>frameRateMultipler</code> ratio is not integral, then <code>effectiveFrameRate</code> will be a non-integral rational.</p></div><div class="note"><p class="prefix"><b>Note:</b></p><p>The begin time of the <a href="#terms-root-temporal-extent">root temporal extent</a> is related to the begin time of a
+<a href="#terms-related-media-object">related media object</a> in accordance with the computed value of the
+<a href="#parameter-attribute-mediaOffset"><code>ttp:mediaOffset</code></a> parameter property.</p></div></div><div class="div2">
 <h3><a id="time-expression-semantics-smpte"></a>N.3 SMPTE Time Base</h3><p>When operating with the <code>smpte</code> time base, the following semantics apply for interpreting time expressions,
 as defined by <a href="#timing-value-timeExpression">&lt;timeExpression&gt;</a>, and their relationship to media time and local real time.</p><p>If the computed value of the <code>ttp:markerMode</code> parameter is <code>discontinuous</code>, then there is no direct relationship between
 time expressions and media time <span class="strong"><code>M</code></span> or local real time <span class="strong"><code>R</code></span>. In
@@ -7957,7 +8276,9 @@
 <br></p></blockquote>
 </td></tr></tbody></table><p>Given the derived media time base as described above, then 
 media time base <span class="strong"><code>M</code></span> is related to the local real time <span class="strong"><code>R</code></span>
-as described in <a href="#time-expression-semantics-media"><b>N.2 Media Time Base</b></a> above.</p></div></div><div class="div1">
+as described in <a href="#time-expression-semantics-media"><b>N.2 Media Time Base</b></a> above.</p><div class="note"><p class="prefix"><b>Note:</b></p><p>The begin time of the <a href="#terms-root-temporal-extent">root temporal extent</a> is related to the begin time of a
+<a href="#terms-related-media-object">related media object</a> in accordance with the computed value of the
+<a href="#parameter-attribute-mediaOffset"><code>ttp:mediaOffset</code></a> parameter property.</p></div></div></div><div class="div1">
 <h2><a id="common-styling"></a>O Common Caption Style Examples (Non-Normative)</h2><p>This section provides examples of the following common caption styles using TTML Content
 to obtain the desired behavior:</p><ul><li><p>Pop-On Captions</p></li><li><p>Roll-Up Captions</p></li><li><p>Paint-On Captions</p></li></ul><div class="div2">
 <h3><a id="pop-on-example"></a>O.1 Pop-On Caption Example</h3><p>An example of paint-on captions. In this example, two regions are targeted with alternating, paint-on content, where content is timed
@@ -8111,5 +8432,5 @@
 by members: Micheal Dolan (SMPTE time codes, streaming; SMPTE liaison), David
 Kirby (introductory example document; SMPTE time codes, descriptive metadata; EBU/AAF liaison), Geoff Freed (styling
 and example images of style properties), Sean Hayes (advanced profile
-concepts, including applicative timing), Eric Hodge (timing),
+concepts, including applicative timing), Erik Hodge (timing),
 Thierry Michel (metadata), and Dave Singer (animation, scrolling).</p><p>The Working Group dedicates this specification to our colleague David Kirby.</p></div></div></body></html>
\ No newline at end of file
--- a/ttml2/spec/ttml2.xml	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/ttml2.xml	Tue Sep 23 15:34:45 2014 -0700
@@ -78,29 +78,29 @@
 <affiliation>Invited Expert</affiliation>
 </author>
 <author>
-<name>Geoff Freed</name>
-<affiliation>WGBH National Center for Accessible Media</affiliation>
-</author>
-<author>
 <name>Sean Hayes</name>
 <affiliation>Microsoft</affiliation>
 </author>
 <author>
-<name>Erik Hodge</name>
-<affiliation>RealNetworks</affiliation>
+<name>Frans de Jong</name>
+<affiliation>European Broadcasting Union</affiliation>
 </author>
 <author>
-<name>David Kirby</name>
-<affiliation>British Broadcasting Corporation (BBC)</affiliation>
+<name>Pierre-Anthony Lemieux</name>
+<affiliation>MovieLabs</affiliation>
 </author>
 <author>
-<name>Thierry Michel</name>
-<affiliation>W3C</affiliation>
+<name>Nigel Megitt</name>
+<affiliation>British Broadcasting Corporation</affiliation>
 </author>
 <author>
 <name>Dave Singer</name>
 <affiliation>Apple Computer</affiliation>
 </author>
+<author>
+<name>Jerry Smith</name>
+<affiliation>Microsoft</affiliation>
+</author>
 </authlist>
 <errataloc href="https://dvcs.w3.org/hg/ttml/raw-file/default/ttml10/spec/ttml-issues.html"/>
 <translationloc href="http://www.w3.org/2003/03/Translations/byTechnology?technology=ttml2"/>
@@ -126,9 +126,7 @@
 <langusage><language id='en-us'>English</language></langusage>
 <revisiondesc><p>Last Modified: $Date$</p></revisiondesc>
 </header>
-
 <body>
-
 <div1 id="intro">
 <head>Introduction</head>
 <p><emph>Unless specified otherwise, this section and its sub-sections are non-normative.</emph></p>
@@ -165,7 +163,6 @@
 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>
 </note>
-
 <div2 id="model">
 <head>System Model</head>
 <p>Use of TTML is intended to function in a wider context of Timed Text
@@ -185,7 +182,6 @@
 </tbody>
 </table>
 </div2> <!-- model -->
-
 <div2 id="example">
 <head>Document Example</head>
 <p>A TTML <loc href="#terms-document-instance">document instance</loc> consists of a <el>tt</el> document element that contains
@@ -489,7 +485,6 @@
 and may specify inline overrides to styling.</p>
 </div2> <!-- example -->
 </div1> <!-- intro -->
-
 <div1 id="definitions">
 <head>Definitions</head>
 <div2 id="acronyms">
@@ -502,6 +497,12 @@
 </def>
 </gitem>
 <gitem>
+<label>ISD</label>
+<def>
+<p>Intermedia Synchronic Document</p>
+</def>
+</gitem>
+<gitem>
 <label>TT</label>
 <def>
 <p>Timed Text</p>
@@ -770,6 +771,26 @@
 time interval. No <att>region</att> attribute makes reference to an inline region.</p>
 </def>
 </gitem>
+<gitem id="terms-intermediate-synchronic-document">
+<label>[intermediate synchronic document]</label>
+<def>
+<p>An abstract or concrete representation of the static content, styling, and layout of a source TTML <loc href="#terms-document-instance">document instance</loc>
+during a non-overlapping temporal interval that intersects with the source document's <loc href="#terms-root-temporal-extent">root temporal extent</loc>.</p>
+</def>
+</gitem>
+<gitem id="terms-intermediate-synchronic-document-sequence">
+<label>[intermediate synchronic document sequence]</label>
+<def>
+<p>An abstract or concrete representation of a sequence of <loc href="#terms-intermediate-synchronic-document">intermediate synchronic document</loc> instances
+that effectively represent the content, styling, layout, and timing of a source TTML <loc href="#terms-document-instance">document instance</loc>.</p>
+</def>
+</gitem>
+<gitem id="terms-intermediate-synchronic-document-sequence-syntax">
+<label>[intermediate synchronic document sequence syntax]</label>
+<def>
+<p>A formalism for use in the concrete representation of an <loc href="#terms-intermediate-synchronic-document-sequence">intermediate synchronic document sequence</loc>.</p>
+</def>
+</gitem>
 <gitem id="terms-nested-profile">
 <label>[nested profile]</label>
 <def>
@@ -1047,7 +1068,6 @@
 </def>
 </gitem>
 </glist>
-
 <p>If normative specification language takes an imperative form,
 then it is to be treated as if the term <phrase role="strong">must</phrase>
 applies. Furthermore, if normative language takes a declarative form,
@@ -1138,7 +1158,6 @@
 </table>
 </div2> <!-- conventions -->
 </div1> <!-- definitions -->
-
 <div1 id="conformance">
 <head>Conformance</head>
 <p>This section specifies the general conformance requirements for
@@ -1182,12 +1201,10 @@
 </item>
 </olist>
 </div2> <!-- conformance-content -->
-
 <div2 id="conformance-processor">
 <head>Processor Conformance</head>
 <div3 id="conformance-generic-processor">
 <head>Generic Processor Conformance</head>
-
 <ednote>
 <name>Profile Processing</name>
 <date>2014-05-21</date>
@@ -1199,7 +1216,6 @@
 <date>2014-05-21</date>
 <edtext>Add requirement to invoke validation processing procedure. Add and use definition of 'validating processor'.</edtext>
 </ednote>
-
 <p>A TTML <loc href="#terms-content-processor">content processor</loc> conforms to this specification if the following
 generic processor criteria are
 satisfied:</p>
@@ -1247,7 +1263,6 @@
 </item>
 </olist>
 </div3> <!-- conformance-generic-processor -->
-
 <div3 id="conformance-transformation-processor">
 <head>Transformation Processor Conformance</head>
 <p>A TTML <loc href="#terms-content-processor">content processor</loc> is a conformant TTML <loc href="#terms-transformation-processor">transformation processor</loc> if
@@ -1268,7 +1283,6 @@
 <edtext>Should we also require support for DFXP Transformation Profile?</edtext>
 </ednote>
 </div3> <!-- conformance-transformation-processor -->
-
 <div3 id="conformance-presentation-processor">
 <head>Presentation Processor Conformance</head>
 <p>A TTML <loc href="#terms-content-processor">content processor</loc> is a conformant TTML <loc href="#terms-presentation-processor">presentation processor</loc> if
@@ -1289,9 +1303,7 @@
 <edtext>Should we also require support for DFXP Presentation Profile?</edtext>
 </ednote>
 </div3> <!-- conformance-presentation-processor -->
-
 </div2> <!-- conformance-processor -->
-
 <div2 id="claims">
 <head>Claims</head>
 <p>Any claim of compliance with respect to the conformance of a TTML <loc href="#terms-document-instance">document instance</loc> or
@@ -1319,7 +1331,6 @@
 support for a <loc href="#terms-feature">feature</loc> not defined by <bibref ref="ttml1"/>.</p>
 </div2> <!-- claims -->
 </div1> <!-- conformance -->
-
 <div1 id="doctypes">
 <head>Document Types</head>
 <p>This section defines the following TTML <emph>Abstract Document Types</emph>:</p>
@@ -1404,7 +1415,6 @@
 </note>
 </div2> <!-- ttml-content-doctype -->
 </div1> <!-- doctypes -->
-
 <div1 id="vocabulary">
 <head>Vocabulary</head>
 <p>This section defines the
@@ -1459,6 +1469,11 @@
 <td><code>http://www.w3.org/ns/ttml#metadata</code></td>
 </tr>
 <tr>
+<td>TT Intermediate Synchronic Document</td>
+<td><code>isd:</code></td>
+<td><code>http://www.w3.org/ns/ttml#isd</code></td>
+</tr>
+<tr>
 <td>TT Profile</td>
 <td><emph>none</emph></td>
 <td><code>http://www.w3.org/ns/ttml/profile/</code></td>
@@ -1478,6 +1493,11 @@
 <note role="clarification">
 <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>If a reference to an attribute is used in this specification and the name
+of the attribute is not namespace qualified, then the attribute is implicitly qualified by
+the element type with which it is used. That is, the attribute resides in the so-called
+<loc href="http://www.w3.org/TR/1999/REC-xml-names-19990114/#ns-breakdown"><emph>per-element-type namespace partition</emph></loc>
+<bibref ref="nsoriginal"/>, the members of which are interpreted in accordance with the definition of the element type on which they appear.</p>
 <p>For certain namespaces defined above, the default prefix
 is specified as <emph>none</emph> if no XML vocabulary is defined in
 the namespace by this specification (nor expected to be defined in a
@@ -1491,46 +1511,36 @@
 <bibref ref="nsstate"/>; all undefined names in these namespaces are reserved for future
 standardization by the W3C.</p>
 </div2> <!-- vocabulary-namespaces -->
-
 <div2 id="vocabulary-profiles">
 <head>Profiles</head>
-
 <p>This section describes the TTML profiling sub-system and high level requirements that apply to this sub-system. At the end of this section
 appears a sub-section containing examples of profile specifications and examples of how these specifications are referenced and used.</p>
-
 <div3 id="vocabulary-profile-introduction">
 <head>Introduction</head>
-
 <p><emph>This sub-section is non-normative.</emph></p>
-
 <p>A given profile may be used by a Timed Text Markup Language content author for one of two functions: (1) to declare that a
 <loc href="#terms-document-instance">document instance</loc> adheres to a collection of constraints on what
 vocabulary is used and how it is used, or (2) to declare that a <loc href="#terms-processor">processor</loc> must satisfy certain conditions on how
 content is processed. The first of these functions is termed a <loc href="#terms-content-profile">content profile</loc>, while
 the second is termed a <loc href="#terms-processor-profile">processor profile</loc>.</p>
-
 <p>A <loc href="#terms-content-profile">content profile</loc> is used to allow an author to declare, at authoring time,
 what constraints the author intends to apply to a <loc href="#terms-document-instance">document instance</loc>. Such a
 declaration permits downstream processors to perform content validation or verification, as well as to guide or limit subsequent
 transformation or editing of content in order to maintain adherence to an author specified content profile. In addition, a
 downstream processor may use a content profile declaration to perform an early determination of its ability to process the features
 implied by the content profile.</p>
-
 <p>Content profiles are declared by using (1) the <loc href="#parameter-attribute-contentProfiles"><att>ttp:contentProfiles</att></loc>
 attribute on the root <el>tt</el> element, (2) one or more top-level <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc>
 elements of type <code>content</code>, or (3) a combination of these two mechanisms. If not declared, no content profile is implied.</p>
-
 <p>A <loc href="#terms-processor-profile">processor profile</loc> is used to allow an author to declare, at authoring time,
 what processing must be supported when processing a <loc href="#terms-document-instance">document instance</loc>, such that, if a
 processor is not able to perform the indicated processing, then processing should be aborted. Such a declaration permits downstream
 processors to avoid processing content that cannot be processed in a manner that meets the requirements of the content author.</p>
-
 <p>Processor profiles are declared by using (1) the <loc href="#parameter-attribute-processorProfiles"><att>ttp:processorProfiles</att></loc>
 attribute on the root <el>tt</el> element, (2) one or more <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc>
 elements of type <code>processor</code>, or (3) a combination of these two mechanisms.
 If not declared, a processor profile is inferred from a declared content profile or from a
 <loc href="#terms-default-profile">default profile</loc>.</p>
-
 <note role="elaboration">
 <p>It is not a requirement on a conformant <loc href="#terms-document-instance">document instance</loc> that a processor profile be internally
 declared by use of a <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc> element or internally referenced by a
@@ -1540,7 +1550,6 @@
 agreement, out-of-band protocol, or common use (between sender and receiver) of a processor profile defined
 by an external specification.</p>
 </note>
-
 <note role="elaboration">
 <p>It is intended that the <att>ttp:processorProfiles</att> attribute be used when
 the author wishes to reference one (or more) of the standard, predefined processor profiles of
@@ -1566,26 +1575,20 @@
 It is also possible to define a derived profile that is simultaneously subtractive
 and additive.</p>
 </note>
-
 <p>A content author is not limited to using a single profile, but may make reference to multiple profiles of either type, i.e.,
 multiple content profiles and/or multiple processor profiles. When multiple profiles are referenced, their respective specifications
 are combined to form a single effective content profile that applies to the document and a single effective processor profile
 that applies to a processor when processing the document. In addition, an author is not limited to making reference to externally
 defined profiles, but may define one or more profiles inline within a document.</p>
-
-</div3>
-
+</div3>
 <div3 id="semantics-profile-examples">
 <head>Profile Examples</head>
-
 <p><emph>This sub-section is non-normative.</emph></p>
-
 <ednote>
 <name>More profile examples.</name>
 <date>2014-05-21</date>
 <edtext>Add more examples depicting new profiling features defined in TTML2.</edtext>
 </ednote>
-
 <p>An example of an author defined
 additive, derived profile of the TTML Presentation
 profile is shown
@@ -1618,29 +1621,23 @@
 in <specref ref="profile-ttml2-presentation"/>). Note also the resetting of the
 default XMLNS binding on the <el>profile</el> element to the TT Parameter Namespace.</p>
 </note>
-
-</div3>
-
+</div3>
 <div3 id="vocabulary-profile-designators">
 <head>Profile Designators</head>
-
 <ednote>
 <name>Reference by designator to internally defined profile.</name>
 <date>2014-05-26</date>
 <edtext>Handle case where a designator refers to an internally defined profile.</edtext>
 </ednote>
-
 <p>A profile is referenced in one of two ways according to whether the profile is defined externally to the referring document or
 is defined inline within the referring document. When defined externally, a profile is referenced by means of a
 <loc href="#terms-profile-designator">profile designator</loc>. When defined internally (inline), a profile is referenced either implicitly
 or by means of <loc href="#terms-profile-fragment-identifier">profile fragment identifier</loc>.</p>
-
 <ednote>
 <name>Profile Fragment Identifiers.</name>
 <date>2014-05-26</date>
 <edtext>Update following to account for use of profile fragment identifier as a profile designator.</edtext>
 </ednote>
-
 <p>A profile designator must adhere to the
 <code>xsd:anyURI</code> data type defined by <bibref ref="xsd-2"/>,
 &sect;3.2.17. If the profile designator is expressed as a relative URI,
@@ -1657,14 +1654,11 @@
 <loc href="#terms-document-instance">document instance</loc>. Nothwithstanding this constraint, a profile designator is not restricted to the set of designators enumerated
 in <specref ref="profile-vocab-table"/>, but may be any URI that feasibly dereferences a TTML <loc href="#terms-profile-definition-document">profile definition document</loc>
 provided it does not use the TT Profile Namespace as a prefix.</p>
-
 <div4 id="vocabulary-profile-standard-designators">
 <head>Standard Designators</head>
-
 <p>The Timed Text Markup Language (TTML) employs a number of
 standard, predefined profiles of its
 vocabulary and associated semantics.</p>
-
 <p>The following table specifies this set of
 profiles, indicating
 a normative name
@@ -1716,19 +1710,14 @@
 <p>For definitions of the DFXP profiles, see <bibref ref="ttml1"/>. For definition of the SDP US profile, see <bibref ref="sdpus"/>.</p>
 </note>
 </div4>
-
-</div3>
-
+</div3>
 <div3 id="semantics-profile-semantics">
 <head>Profile Semantics</head>
-
 <div4 id="semantics-profile-state">
 <head>Profile State Object Concepts</head>
 <p>This section defines a number of conceptual state objects used by subsequently defined algorithms (procedures and functions). It is not required that an
 implementation create such objects in the form specified here, but may use any convenient, internal representation that represents equivalent information.</p>
-
 <glist>
-
 <gitem id="semantics-profile-state-profile-specification">
 <label>[profile specification]</label>
 <def>
@@ -1758,7 +1747,6 @@
 </glist>
 </def>
 </gitem>
-
 <gitem id="semantics-profile-state-combined-profile-specification-set">
 <label>[combined profile specification set]</label>
 <def>
@@ -1784,7 +1772,6 @@
 </glist>
 </def>
 </gitem>
-
 <gitem id="semantics-profile-state-empty-profile-specification-set">
 <label>[empty profile specification set]</label>
 <def>
@@ -1793,7 +1780,6 @@
 <loc href="#semantics-profile-state-combined-profile-specification-set-specifications"><phrase role="strong">specifications</phrase></loc> fields are empty sets</p>
 </def>
 </gitem>
-
 <gitem id="semantics-profile-state-profile">
 <label>[profile]</label>
 <def>
@@ -1848,20 +1834,15 @@
 </glist>
 </def>
 </gitem>
-
 </glist>
-
 </div4>
-
 <div4 id="semantics-content-profile-processing">
 <head>Content Profile Semantics</head>
-
 <ednote>
 <name>Validation Processing</name>
 <date>2014-05-21</date>
 <edtext>Add validation processing procedures.</edtext>
 </ednote>
-
 <glist>
 <gitem id="semantics-procedure-construct-effective-content-profile">
 <label>[construct effective content profile]</label>
@@ -1920,12 +1901,9 @@
 </def>
 </gitem>
 </glist>
-
 </div4>
-
 <div4 id="semantics-processor-profile-processing">
 <head>Processor Profile Semantics</head>
-
 <glist>
 <gitem id="semantics-procedure-abort-if-unsupported-processor-profile">
 <label>[abort if unsupported processor profile]</label>
@@ -2004,7 +1982,6 @@
 </olist>
 </def>
 </gitem>
-
 <gitem id="semantics-procedure-construct-inferred-processor-profile">
 <label>[construct inferred processor profile]</label>
 <def>
@@ -2063,7 +2040,6 @@
 </olist>
 </def>
 </gitem>
-
 <gitem id="semantics-procedure-construct-default-processor-profile">
 <label>[construct default processor profile]</label>
 <def>
@@ -2074,7 +2050,6 @@
 from which a <loc href="#terms-processor-profile">processor profile</loc> can be inferred, then the
 <loc href="#terms-default-processor-profile">default processor profile</loc> is that <loc href="#terms-processor-profile">processor profile</loc>;</p>
 </item>
-
 <item>
 <p>otherwise, if the <loc href="#terms-content-processor">content processor</loc> is primarily characterized as a
 <loc href="#terms-presentation-processor">presentation processor</loc>, then:</p>
@@ -2101,7 +2076,6 @@
 </item>
 </olist>
 </item>
-
 <item>
 <p>otherwise, if the <loc href="#terms-content-processor">content processor</loc> is primarily characterized as a
 <loc href="#terms-transformation-processor">transformation processor</loc>, then:</p>
@@ -2139,13 +2113,9 @@
 </gitem>
 </glist>
 
-
 </div4>
-
-</div3>
-
+</div3>
 </div2> <!-- vocabulary-profiles -->
-
 <div2 id="vocabulary-overview">
 <head>Catalog</head>
 <p>The vocabulary of the Timed Text Markup Language (TTML) is
@@ -2267,6 +2237,7 @@
 </td>
 <td>
 <loc href="#styling-vocabulary-styling">styling</loc>,
+<loc href="#styling-vocabulary-initial">initial</loc>,
 <loc href="#styling-vocabulary-style">style</loc>
 </td>
 </tr>
@@ -2284,7 +2255,7 @@
 <th>Group</th>
 <th>Elements</th>
 </tr>
-<tr>
+<tr id="element-vocab-group-animation">
 <td>
 Animation.class
 </td>
@@ -2293,7 +2264,7 @@
 <loc href="#animation-vocabulary-set">set</loc>
 </td>
 </tr>
-<tr>
+<tr id="element-vocab-group-block">
 <td>
 Block.class
 </td>
@@ -2302,7 +2273,7 @@
 <loc href="#content-vocabulary-p">p</loc>
 </td>
 </tr>
-<tr>
+<tr id="element-vocab-group-inline">
 <td>
 Inline.class
 </td>
@@ -2316,11 +2287,11 @@
 <td>
 Layout.class
 </td>
-<td>
+<td id="element-vocab-group-layout">
 <loc href="#layout-vocabulary-region">region</loc>
 </td>
 </tr>
-<tr>
+<tr id="element-vocab-group-metadata">
 <td>
 Metadata.class
 </td>
@@ -2332,7 +2303,7 @@
 <loc href="#metadata-vocabulary-title">ttm:title</loc>
 </td>
 </tr>
-<tr>
+<tr id="element-vocab-group-parameters">
 <td>Parameters.class</td>
 <td><loc
 href="#parameter-vocabulary-profile">ttp:profile</loc></td>
@@ -2352,7 +2323,7 @@
 <th>Module</th>
 <th>Attributes</th>
 </tr>
-<tr>
+<tr id="attribute-vocab-group-animation-binding">
 <td>
 Animation Binding Attribute
 </td>
@@ -2360,7 +2331,7 @@
 <loc href="#animation-attribute-animate">animate</loc>
 </td>
 </tr>
-<tr>
+<tr id="attribute-vocab-group-core">
 <td>
 Core Attributes
 </td>
@@ -2370,7 +2341,7 @@
 <loc href="#content-attribute-space">xml:space</loc>
 </td>
 </tr>
-<tr>
+<tr id="attribute-vocab-group-layout-binding">
 <td>
 Layout Binding Attribute
 </td>
@@ -2378,7 +2349,7 @@
 <loc href="#layout-attribute-region">region</loc>
 </td>
 </tr>
-<tr>
+<tr id="attribute-vocab-group-metadata">
 <td>
 Metadata Attributes
 </td>
@@ -2387,7 +2358,7 @@
 <loc href="#metadata-attribute-role">ttm:role</loc>
 </td>
 </tr>
-<tr>
+<tr id="attribute-vocab-group-parameters">
 <td>
 Parameter Attributes
 </td>
@@ -2402,6 +2373,8 @@
 <loc href="#parameter-attribute-inferProcessorProfileMethod">ttp:inferProcessorProfileMethod</loc>,
 <loc href="#parameter-attribute-inferProcessorProfileSource">ttp:inferProcessorProfileSource</loc>,
 <loc href="#parameter-attribute-markerMode">ttp:markerMode</loc>,
+<loc href="#parameter-attribute-mediaDuration">ttp:mediaDuration</loc>,
+<loc href="#parameter-attribute-mediaOffset">ttp:mediaOffset</loc>,
 <loc href="#parameter-attribute-permitFeatureNarrowing">ttp:permitFeatureNarrowing</loc>,
 <loc href="#parameter-attribute-permitFeatureWidening">ttp:permitFeatureWidening</loc>,
 <loc href="#parameter-attribute-pixelAspectRatio">ttp:pixelAspectRatio</loc>,
@@ -2416,7 +2389,7 @@
 <loc href="#parameter-attribute-version">ttp:version</loc>
 </td>
 </tr>
-<tr>
+<tr id="attribute-vocab-group-style-binding">
 <td>
 Style Binding Attribute
 </td>
@@ -2424,7 +2397,7 @@
 <loc href="#style-attribute-style">style</loc>
 </td>
 </tr>
-<tr>
+<tr id="attribute-vocab-group-style">
 <td>
 Styling Attributes
 </td>
@@ -2445,6 +2418,9 @@
 <loc href="#style-attribute-origin">tts:origin</loc>,
 <loc href="#style-attribute-overflow">tts:overflow</loc>,
 <loc href="#style-attribute-padding">tts:padding</loc>,
+<loc href="#style-attribute-ruby">tts:ruby</loc>,
+<loc href="#style-attribute-rubyAlign">tts:rubyAlign</loc>,
+<loc href="#style-attribute-rubyPosition">tts:rubyPosition</loc>,
 <loc href="#style-attribute-showBackground">tts:showBackground</loc>,
 <loc href="#style-attribute-textAlign">tts:textAlign</loc>,
 <loc href="#style-attribute-textDecoration">tts:textDecoration</loc>,
@@ -2457,7 +2433,7 @@
 <loc href="#style-attribute-zIndex">tts:zIndex</loc>
 </td>
 </tr>
-<tr>
+<tr id="attribute-vocab-group-timing">
 <td>
 Timing Attributes
 </td>
@@ -2499,7 +2475,6 @@
 </div3>
 </div2> <!-- vocabulary-overview -->
 </div1> <!-- vocabulary -->
-
 <div1 id="parameters">
 <head>Parameters</head>
 <p>This section specifies the <emph>parameters</emph> matter of the
@@ -2777,7 +2752,10 @@
 feature referenced by the <att>extends</att> attribute.
 The <att>restricts</att> attribute may be used to indicate that the feature being defined
 is, from either (or both) a syntactic or (and) semantic perspective, a proper subset of the
-feature referenced by the <att>restricts</att> attribute.</p>
+feature referenced by the <att>restricts</att> attribute.
+If an <att>extends</att> attribute is specified, then a <att>restricts</att> attribute must
+not be specified on a <el>ttp:feature</el> element; likewise, if a <att>restricts</att> attribute
+is specified, then an <att>extends</att> attribute must not be specified.</p>
 <p>If the URI expressed by (1) the content of the <el>ttp:feature</el>
 element, (2) the <att>extends</att> attribute, or (3) the <att>restricts</att> attribute
 is a relative URI, then, when combined with the
@@ -2984,8 +2962,11 @@
 is, from either (or both) a syntactic or (and) semantic perspective, a proper superset of the
 feature or extension referenced by the <att>extends</att> attribute.
 The <att>restricts</att> attribute may be used to indicate that the extension being defined
-is, from either (or both) a syntacitc or (and) semantic perspective, a proper subset of the
-feature or extension referenced by the <att>restricts</att> attribute.</p>
+is, from either (or both) a syntactic or (and) semantic perspective, a proper subset of the
+feature or extension referenced by the <att>restricts</att> attribute.
+If an <att>extends</att> attribute is specified, then a <att>restricts</att> attribute must
+not be specified on a <el>ttp:extension</el> element; likewise, if a <att>restricts</att> attribute
+is specified, then an <att>extends</att> attribute must not be specified.</p>
 <p>If the URI expressed by (1) the content of the <el>ttp:extension</el>
 element, (2) the <att>extends</att> attribute, or (3) the <att>restricts</att> attribute
 is a relative URI, then, when combined with the
@@ -2997,7 +2978,7 @@
 element must further adhere to the syntax of an extension designation as
 defined by <specref ref="extension-designations"/>,
 while the URI expressed by the <att>extends</att> attribute and/or the
-<att>restricts</att> attribute must ahdere to the syntax of a feature designation
+<att>restricts</att> attribute must adhere to the syntax of a feature designation
 or an extension designation as defined by <specref ref="feature-designations"/> or
 <specref ref="extension-designations"/>, respectively.</p>
 <p>If the URI expressed by the content of the <el>ttp:extension</el> element,
@@ -3070,7 +3051,6 @@
 <p>The value <phrase role="obsoleted"><code>use</code></phrase> of the <att>value</att> attribute is <phrase role="obsoleted">obsoleted</phrase>. If it
 appears in a profile specification, then it must be interpreted as if <code>required</code>
 had been specified.</p>
-
 <p>If some well known extension is not specified by
 a <el>ttp:extension</el> element in a content profile, then it must be interpreted as if the extension were specified
 with the <att>value</att> attribute equal to <code>optional</code>. However, if not specified in a processor profile, no claim
@@ -3115,7 +3095,6 @@
 </note>
 </div3>
 </div2> <!-- parameter-element-vocabulary -->
-
 <div2 id="parameter-attribute-vocabulary">
 <head>Parameter Attribute Vocabulary</head>
 <p>The following attributes are defined in the TT Parameter Namespace.</p>
@@ -3130,6 +3109,8 @@
 <item><p><specref ref="parameter-attribute-inferProcessorProfileMethod"/></p></item>
 <item><p><specref ref="parameter-attribute-inferProcessorProfileSource"/></p></item>
 <item><p><specref ref="parameter-attribute-markerMode"/></p></item>
+<item><p><specref ref="parameter-attribute-mediaDuration"/></p></item>
+<item><p><specref ref="parameter-attribute-mediaOffset"/></p></item>
 <item><p><specref ref="parameter-attribute-permitFeatureNarrowing"/></p></item>
 <item><p><specref ref="parameter-attribute-permitFeatureWidening"/></p></item>
 <item><p><specref ref="parameter-attribute-pixelAspectRatio"/></p></item>
@@ -3161,7 +3142,6 @@
 <eg xml:space="preserve">
 ttp:cellResolution
   : columns rows                            // <emph>columns</emph> != 0; <emph>rows</emph> != 0
-
 columns | rows
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>+
 </eg>
@@ -3270,13 +3250,10 @@
   : designators
   | "all(" designators ")"
   | "any(" designators ")"
-
 designators
   : designator (lwsp designator)*
-
 designator
   : xsd:anyURI
-
 lwsp
   : ( ' ' | '\t' | '\n' | '\r' )+
 </eg>
@@ -3534,7 +3511,6 @@
 <eg xml:space="preserve">
 ttp:frameRateMultiplier
   : numerator denominator                   // <emph>numerator</emph> != 0; <emph>denominator</emph> != 0
-
 numerator | denominator
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>+
 </eg>
@@ -3757,6 +3733,84 @@
 </p>
 </note>
 </div3>
+<div3 id="parameter-attribute-mediaDuration">
+<head>ttp:mediaDuration</head>
+<p>The <att>ttp:mediaDuration</att> attribute is used to specify the
+temporal extent (simple duration) of a <loc href="#terms-related-media-object">related media object</loc>.</p>
+<p>If the temporal extent (simple duration) of the <loc href="#terms-related-media-object">related media object</loc> is known at authoring time, then this
+attribute should be specified; otherwise, if no <loc href="#terms-related-media-object">related media object</loc> applies or its
+temporal extent is unknown, then this attribute should not be specified.</p>
+<p>If specified, the value of this attribute must adhere to the following syntax:</p>
+<table id="parameter-attribute-mediaDuration-syntax" role="syntax">
+<caption>Syntax Representation &ndash; ttp:mediaDuration</caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+ttp:mediaDuration
+  : <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>                        // restricted to <emph>offset-time</emph> form
+  | "indefinite"
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<p>If specified, the value of this parameter must either (1) adhere to the <emph>offset-time</emph> form of
+a <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc> or (2) take the value <code>indefinite</code>.</p>
+<p>If the value <code>indefinite</code> is specified, then there is no <loc href="#terms-related-media-object">related media object</loc>,
+the temporal extent (simple duration) of the
+<loc href="#terms-related-media-object">related media object</loc> is not known at the time this attribute is
+encoded, or the <loc href="#terms-related-media-object">related media object</loc> has no temporal end point.</p>
+<p>If not specified, the value of this parameter must be considered
+to be <code>indefinite</code>.</p>
+<p>A <att>ttp:mediaDuration</att> attribute is considered to be significant only
+when specified on the <el>tt</el> element.</p>
+<note role="explanation">
+<p>See <specref ref="timing-time-value-expressions"/> for the
+specification of time expression syntax and semantics.</p>
+</note>
+</div3>
+<div3 id="parameter-attribute-mediaOffset">
+<head>ttp:mediaOffset</head>
+<p>The <att>ttp:mediaOffset</att> attribute is used to specify the
+temporal offset between the begin time of the <loc href="#terms-root-temporal-extent">root temporal extent</loc>
+and the begin time of a <loc href="#terms-related-media-object">related media object</loc> when operating in a
+<loc href="#time-expression-semantics-media">Media Time Base</loc>
+or a <loc href="#time-expression-semantics-smpte">SMPTE Time Base</loc>. It does not apply and
+must not be specified when operating in a <loc href="#time-expression-semantics-clock">Clock Time Base</loc>.</p>
+<p>If specified, the value of this attribute must adhere to the following syntax:</p>
+<table id="parameter-attribute-mediaOffset-syntax" role="syntax">
+<caption>Syntax Representation &ndash; ttp:mediaOffset</caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+ttp:mediaOffset
+  : sign? <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>                  // restricted to <emph>offset-time</emph> form
+sign
+  : "+" | "-"
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<p>If specified, the value of this parameter must adhere to the <emph>offset-time</emph> form of
+a <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc> optionally expressed with a sign.
+If not specified, the value of this parameter must be considered
+to be <code>0s</code>.</p>
+<p>If no sign is specified or it is specified as <code>+</code>, then the begin time of the
+<loc href="#terms-root-temporal-extent">root temporal extent</loc> follows the begin time of the
+<loc href="#terms-related-media-object">related media object</loc>; otherwise (sign is present and
+specified as <code>-</code>), the begin time of the
+<loc href="#terms-root-temporal-extent">root temporal extent</loc> precedes the begin time of the
+<loc href="#terms-related-media-object">related media object</loc>.</p>
+<p>A <att>ttp:mediaOffset</att> attribute is considered to be significant only
+when specified on the <el>tt</el> element.</p>
+<note role="explanation">
+<p>See <specref ref="timing-time-value-expressions"/> for the
+specification of time expression syntax and semantics.</p>
+</note>
+</div3>
 <div3 id="parameter-attribute-permitFeatureNarrowing">
 <head>ttp:permitFeatureNarrowing</head>
 <p>The <att>ttp:permitFeatureNarrowing</att> attribute is used to specify whether
@@ -3829,7 +3883,6 @@
 <eg xml:space="preserve">
 ttp:pixelAspectRatio
   : width height                            // <emph>width</emph> != 0; <emph>height</emph> != 0
-
 width | height
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>+
 </eg>
@@ -3873,7 +3926,6 @@
 <eg xml:space="preserve">
 <phrase role="deprecated">ttp:profile</phrase>
   : designator
-
 designator
   : xsd:anyURI
 </eg>
@@ -3910,13 +3962,10 @@
   : designators
   | "all(" designators ")"
   | "any(" designators ")"
-
 designators
   : designator (lwsp designator)*
-
 designator
   : xsd:anyURI
-
 lwsp
   : ( ' ' | '\t' | '\n' | '\r' )+
 </eg>
@@ -3932,7 +3981,6 @@
 attribute is considered to be significant only when specified on the
 <el>tt</el> element.</p>
 </div3>
-
 <div3 id="parameter-attribute-processorProfileCombination">
 <head>ttp:processorProfileCombination</head>
 <p>The <att>ttp:processorProfileCombination</att> attribute is used to specify the
@@ -4172,7 +4220,6 @@
 on the interpretation of time expressions according to the designated time base.</p>
 </note>
 </div3>
-
 <div3 id="parameter-attribute-validation">
 <head>ttp:validation</head>
 <p>The <att>ttp:validation</att> attribute is used to specify whether validation processing
@@ -4186,19 +4233,23 @@
 <td>
 <eg xml:space="preserve">
 ttp:validation
-  : "optional"
-  | "required"
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
+  : "required"
+  | "optional"
+  | "prohibited"
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<p>If this parameter's value is <code>required</code>, then, a <loc href="#terms-validating-content-processor">validating content processor</loc>
+must perform validation processing on a TTML <loc href="#terms-document-instance">document instance</loc> prior to performing
+other types of processing, e.g., presentation or transformation processing.</p>
 <p>If this parameter's value is <code>optional</code>, then, a <loc href="#terms-validating-content-processor">validating content processor</loc>
 may, but need not, perform validation processing on a TTML <loc href="#terms-document-instance">document instance</loc> prior to performing
 other types of processing, e.g., presentation or transformation processing.</p>
-<p>If this parameter's value is <code>required</code>, then, a <loc href="#terms-validating-content-processor">validating content processor</loc>
-must perform validation processing on a TTML <loc href="#terms-document-instance">document instance</loc> prior to performing
-other types of processing, e.g., presentation or transformation processing.</p>
+<p>If this parameter's value is <code>prohibited</code>, then, a <loc href="#terms-validating-content-processor">validating content processor</loc>
+must not perform validation processing on a TTML <loc href="#terms-document-instance">document instance</loc> prior to performing
+other types of processing, e.g., presentation or transformation processing, unless the end-user or application overrides this prohibition.</p>
 <p>If validation processing is performed on a TTML <loc href="#terms-document-instance">document instance</loc> and validation fails, then the computed value of
 the <att>ttp:validationAction</att> parameter property is used to determine what action to take before performing further processing.</p>
 <p>If not specified, the value of this parameter must be considered
@@ -4206,7 +4257,6 @@
 <p>A <att>ttp:validation</att> attribute is considered to be significant only
 when specified on the <el>tt</el> element.</p>
 </div3>
-
 <div3 id="parameter-attribute-validationAction">
 <head>ttp:validationAction</head>
 <p>The <att>ttp:validationAction</att> attribute is used to specify what action is to be taken
@@ -4235,12 +4285,15 @@
 <p>If this parameter's value is <code>ignore</code>, then, a <loc href="#terms-validating-content-processor">validating content processor</loc>
 should not abort and should not warn the end-user when validation processing fails.</p>
 <p>If not specified, the value of this parameter is determined as follows:
-if the computed value of the <loc href="#parameter-attribute-validation"><att>ttp:validation</att></loc> parameter property is <code>optional</code>,
-then the value must be considered to be <code>warn</code>; otherwise, it must be considered to be <code>abort</code>.</p>
+if the computed value of the <loc href="#parameter-attribute-validation"><att>ttp:validation</att></loc> parameter property is <code>required</code>,
+then the value must be considered to be <code>abort</code>;
+if it is <code>optional</code>,
+then the value must be considered to be <code>warn</code>;
+otherwise, if it is <code>prohibited</code>,
+then the value must be considered to be <code>ignore</code>.</p>
 <p>A <att>ttp:validationAction</att> attribute is considered to be significant only
 when specified on the <el>tt</el> element.</p>
 </div3>
-
 <div3 id="parameter-attribute-version">
 <head>ttp:version</head>
 <p>The <att>ttp:version</att> attribute is used to specify which version of the
@@ -4291,7 +4344,6 @@
 </div3>
 </div2> <!-- parameter-attribute-vocabulary -->
 </div1> <!-- parameters -->
-
 <div1 id="content">
 <head>Content</head>
 <p>This section specifies the <emph>content</emph> matter of the core
@@ -4326,6 +4378,7 @@
   <loc href="#content-attribute-lang"><phrase role="reqattr">xml:lang</phrase></loc> = string
   <loc href="#content-attribute-space">xml:space</loc> = (<emph>default</emph>|<emph>preserve</emph>) : default
   {<emph>any attribute in TT Parameter namespace</emph>}
+  {<emph>any attribute in TT Style namespace</emph>}
   {<emph>any attribute not in default or any TT namespace</emph>}&gt;
   <emph>Content:</emph> <loc href="#document-structure-vocabulary-head">head</loc>?, <loc href="#document-structure-vocabulary-body">body</loc>?
 &lt;/tt&gt;
@@ -4360,6 +4413,9 @@
 This would permit, for example, the interchange of information that reflects the
 the semantics of <bibref ref="cea708e"/> , &sect;4.5 “Caption Service Metadata”, “ASPECT RATIO”.</p>
 </note>
+<p>Except for the <att>tts:extent</att> attribute described above, an attribute in the TT Style Namespace should not be specified on the <el>tt</el> element
+unless it denotes an inheritable style property, and, if specified, must be ignored for the purpose of non-validation processing. In the case of validation
+processing, such usage should be reported as a warning, or, if strict validation is performed, as an error.</p>
 <p>An <att>xml:lang</att> attribute must be specified on the <el>tt</el> element.
 If the attribute value is empty, it signifies that there is no default language that applies
 to the text contained within the <loc href="#terms-document-instance">document instance</loc>.</p>
@@ -4853,7 +4909,6 @@
 </div3>
 </div2> <!-- content-attribute-vocabulary -->
 </div1> <!-- content -->
-
 <div1 id="styling">
 <head>Styling</head>
 <p>This section specifies the <emph>styling</emph> matter of the core
@@ -4884,6 +4939,7 @@
 <loc href="#terms-document-instance">document instance</loc>:</p>
 <ulist>
 <item><p><specref ref="styling-vocabulary-styling"/></p></item>
+<item><p><specref ref="styling-vocabulary-initial"/></p></item>
 <item><p><specref ref="styling-vocabulary-style"/></p></item>
 </ulist>
 <div3 id="styling-vocabulary-styling">
@@ -4891,8 +4947,9 @@
 <p>The <el>styling</el> element is a container element used to group
 styling matter, including metadata that applies to styling matter.</p>
 <p>The <el>styling</el> element accepts as its children zero or more
-elements in the <code>Metadata.class</code> element group, followed by
-zero or more <el>style</el> elements.</p>
+elements in the <code>Metadata.class</code> element group,
+followed by zero or more <el>initial</el> elements,
+followed by zero or more <el>style</el> elements.</p>
 <table id="elt-syntax-styling" role="syntax">
 <caption>XML Representation &ndash; Element Information Item: styling</caption>
 <tbody>
@@ -4904,7 +4961,7 @@
   <loc href="#content-attribute-lang">xml:lang</loc> = string
   <loc href="#content-attribute-space">xml:space</loc> = (<emph>default</emph>|<emph>preserve</emph>)
   {<emph>any attribute not in default or any TT namespace</emph>}&gt;
-  <emph>Content:</emph> <loc href="#element-vocab-group-table">Metadata.class</loc>*, <loc href="#styling-vocabulary-style">style</loc>*
+  <emph>Content:</emph> <loc href="#element-vocab-group-table">Metadata.class</loc>*, <loc href="#styling-vocabulary-initial">initial</loc>*, <loc href="#styling-vocabulary-style">style</loc>*
 &lt;/styling&gt;
 </eg>
 </td>
@@ -4915,6 +4972,51 @@
 <el>styling</el> element, the implied time interval of this element is
 defined to be coterminous with the <loc href="#terms-root-temporal-extent">root temporal extent</loc>.</p>
 </div3>
+<div3 id="styling-vocabulary-initial">
+<head>initial</head>
+<p>The <el>initial</el> element is used to modify the initial value of one or more style properties, i.e, to specify use of different value(s) than
+the specification defined initial value(s).</p>
+<p>The <el>initial</el> element accepts as its children zero or more <el>metadata</el> elements.</p>
+<table id="elt-syntax-initial" role="syntax">
+<caption>XML Representation &ndash; Element Information Item: initial</caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+&lt;initial
+  <loc href="#content-attribute-id">xml:id</loc> = ID
+  <loc href="#content-attribute-lang">xml:lang</loc> = string
+  <loc href="#content-attribute-space">xml:space</loc> = (<emph>default</emph>|<emph>preserve</emph>)
+  {<emph>any attribute in TT Style namespace</emph>}
+  {<emph>any attribute not in default or any TT namespace</emph>}&gt;
+  <emph>Content:</emph> <loc href="#element-vocab-group-table">Metadata.class</loc>*
+&lt;/initial&gt;
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<p>The <el>initial</el> element is illustrated by the following example, wherein
+the initial value of the <att>tts:color</att> property is defined to be <code>yellow</code>.</p>
+<table id="style-vocabulary-initial-example-1" role="example">
+<caption>Example Fragment &ndash; <el>initial</el></caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+...
+&lt;head&gt;
+  &lt;styling&gt;
+    <phrase role="strong">&lt;initial tts:color="yellow"/&gt;</phrase>
+  &lt;styling&gt;
+&lt;head&gt;
+...
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+</div3>
 <div3 id="styling-vocabulary-style">
 <head>style</head>
 <p>The <el>style</el> element is used to define
@@ -4955,7 +5057,6 @@
 </note>
 </div3>
 </div2> <!-- styling-element-vocabulary -->
-
 <div2 id="styling-attribute-vocabulary">
 <head>Styling Attribute Vocabulary</head>
 <p>This section defines the <specref ref="style-attribute-style"/> attribute used
@@ -4980,6 +5081,9 @@
 <item><p><specref ref="style-attribute-origin"/></p></item>
 <item><p><specref ref="style-attribute-overflow"/></p></item>
 <item><p><specref ref="style-attribute-padding"/></p></item>
+<item><p><specref ref="style-attribute-ruby"/></p></item>
+<item><p><specref ref="style-attribute-rubyAlign"/></p></item>
+<item><p><specref ref="style-attribute-rubyPosition"/></p></item>
 <item><p><specref ref="style-attribute-showBackground"/></p></item>
 <item><p><specref ref="style-attribute-textAlign"/></p></item>
 <item><p><specref ref="style-attribute-textDecoration"/></p></item>
@@ -4998,6 +5102,11 @@
 in order to provide a means to independently express styling of the four different borders (top, right, bottom, left). As currently specified, i.e., with only the
 <code>tts:border</code> attribute, one can only express the four borders using the same color, style, and width.</edtext>
 </ednote>
+<p>Unless explicitly permitted by an element type definition, an attribute in the TT Style Namespace should not be specified on an element
+unless it either applies to that element or denotes an inheritable style property. If it does not apply to that element
+and does not denote an inheritable style property, then it must be ignored for the purpose of non-validation processing.
+In the case of validation processing, such usage should be reported as a warning, or, if strict validation is performed,
+as an error.</p>
 <p>Unless explicitly stated otherwise, linear white-space (LWSP) must
 appear between adjacent non-terminal components of a value of a TT
 Style property value unless some other delimiter is permitted and used.</p>
@@ -5009,7 +5118,8 @@
 properties.</p>
 </note>
 <note role="clarification">
-<p>A style property may be expressed as a specified attribute on any
+<p>An inheritable style property may be expressed as a specified attribute on the
+root <loc href="#document-structure-vocabulary-tt"><el>tt</el></loc> element or on a
 <loc href="#terms-content-element">content element</loc> type
 independently of whether the property applies to that
 element type. This capability permits the expression of an inheritable
@@ -5148,7 +5258,6 @@
 that defined by <bibref ref="xsl11"/>, &sect; 7.8.2.</p>
 </note>
 </div3>
-
 <div3 id="style-attribute-border">
 <head>tts:border</head>
 <p>The <att>tts:border</att> attribute is used to specify a style property that
@@ -5267,7 +5376,6 @@
 that defined by <bibref ref="xsl11"/>, &sect; 7.31.3.</p>
 </note>
 </div3>
-
 <div3 id="style-attribute-color">
 <head>tts:color</head>
 <p>The <att>tts:color</att> attribute is used to specify a style property that
@@ -6627,18 +6735,15 @@
 </tbody>
 </table>
 <p>If the value of this attribute is <code>visible</code>, then content should
-not be clipped outside of the affected region, and region composition and layout
-must be performed as if the region's width and height were
-unconstrained,
-but with
-a well-defined origin.  If the value is <code>hidden</code>, then content should
+not be clipped outside of the affected region.
+If the value is <code>hidden</code>, then content should
 be clipped outside of the affected region.</p>
 <note role="explanation">
 <p>Unless a manual line break element <el>br</el> is used by the content author,
 a paragraph of a given region will generate no more than one line area in that
-region if the value of the <att>tts:overflow</att> style that applies to the
-region is <code>visible</code> and if the applicable <att>tts:wrapOption</att>
-style is <code>noWrap</code>.</p>
+region if the computed values of the <att>tts:overflow</att> and <att>tts:wrapOption</att>
+style properties of the region are <code>visible</code> and <code>noWrap</code>,
+respectively.</p>
 </note>
 <p>If a computed value of the property associated with this attribute is not supported,
 then a <loc href="#terms-presentation-processor">presentation processor</loc> must use the value <code>hidden</code>.</p>
@@ -6827,6 +6932,349 @@
 &sect; 7.8.31, 7.8.32, 7.8.33, and 7.8.34.</p>
 </note>
 </div3>
+<div3 id="style-attribute-ruby">
+<head>tts:ruby</head>
+<p>The <att>tts:ruby</att> attribute is used to specify the application of ruby
+styling.</p>
+<p>This attribute applies only to <loc href="#content-vocabulary-span"><el>span</el></loc> elements and is not inheritable, so it should
+not be specified on any other element type. If specified elsewhere, then it must be ignored for
+the purpose of presentation processing.</p>
+<table id="style-property-details-ruby" role="common">
+<col width="25%"/>
+<col/>
+<tbody>
+<tr>
+<td><emph>Values:</emph></td>
+<td>
+<code>none</code> |
+<code>container</code> |
+<code>base</code> |
+<code>baseContainer</code> |
+<code>text</code> |
+<code>textContainer</code> |
+<code>delimiter</code>
+</td>
+</tr>
+<tr>
+<td><emph>Initial:</emph></td>
+<td><code>none</code></td>
+</tr>
+<tr>
+<td><emph>Applies to:</emph></td>
+<td>
+<loc href="#content-vocabulary-span"><el>span</el></loc>
+</td>
+</tr>
+<tr>
+<td><emph>Inherited:</emph></td>
+<td>no</td>
+</tr>
+<tr>
+<td><emph>Percentages:</emph></td>
+<td>N/A</td>
+</tr>
+<tr>
+<td><emph>Animatable:</emph></td>
+<td>discrete</td>
+</tr>
+</tbody>
+</table>
+<p></p>
+<p>If the value of this attribute is <code>none</code>, then no ruby semantics apply; otherwise, the ruby semantics enumerated by
+<specref ref="ruby-semantics-mapping-table"/> apply, where the maximal content model defined by <bibref ref="ruby"/>, &sect;2.1, applies
+and must be treated as an error if violated.</p>
+<p>If a computed value of the property associated with this attribute is not supported,
+then a <loc href="#terms-presentation-processor">presentation processor</loc> must use the value <code>none</code>.</p>
+<table id="ruby-semantics-mapping-table" role="common">
+<caption>Table 8-1 &ndash; Ruby Semantics Mapping</caption>
+<col width="25%"/>
+<col width="25%"/>
+<col width="25%"/>
+<col width="25%"/>
+<col/>
+<tbody>
+<tr>
+<th>Category</th>
+<th>tts:ruby</th>
+<th>Annotation <bibref ref="ruby"/></th>
+<th>CSS display <bibref ref="cssruby"/></th>
+</tr>
+<tr>
+<td>Ruby Container</td>
+<td><code>container</code></td>
+<td><code>ruby</code></td>
+<td><code>ruby</code></td>
+</tr>
+<tr>
+<td>Ruby Base Content</td>
+<td><code>base</code></td>
+<td><code>rb</code></td>
+<td><code>ruby-base</code></td>
+</tr>
+<tr>
+<td>Ruby Text Content</td>
+<td><code>text</code></td>
+<td><code>rt</code></td>
+<td><code>ruby-text</code></td>
+</tr>
+<tr>
+<td>Ruby Base Container</td>
+<td><code>baseContainer</code></td>
+<td><code>rbc</code></td>
+<td><code>ruby-base-container</code></td>
+</tr>
+<tr>
+<td>Ruby Text Container</td>
+<td><code>textContainer</code></td>
+<td><code>rtc</code></td>
+<td><code>ruby-text-container</code></td>
+</tr>
+<tr>
+<td>Ruby Fallback Delimiter</td>
+<td><code>delimiter</code></td>
+<td><code>rp</code></td>
+<td><code>none</code></td>
+</tr>
+</tbody>
+</table>
+<p>Use of <att>tts:ruby</att> to specify simple ruby annotation is illustrated by the following example.</p>
+<table id="style-attribute-ruby-example-1" role="example">
+<caption>Example Fragment &ndash; Simple Ruby</caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+&lt;span <phrase role="strong">tts:ruby="container"</phrase>&gt;
+  &lt;span <phrase role="strong">tts:ruby="base"</phrase>&gt;&#x5229;&#x7528;&#x8A31;&#x8AFE;&lt;/span&gt;
+  &lt;span <phrase role="strong">tts:ruby="text"</phrase>&gt;&#x30E9;&#x30A4;&#x30BB;&#x30F3;&#x30B9;&lt;/span&gt;
+&lt;/span&gt;
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<p></p>
+<table id="style-attribute-ruby-example-1-images" role="example-images">
+<caption>Example Rendition &ndash; Simple Ruby</caption>
+<tbody>
+<tr>
+<td><graphic source="images/ruby_1.png" alt="TTML ruby style property"/></td>
+</tr>
+</tbody>
+</table>
+<p>Use of <att>tts:ruby</att> to specify complex ruby annotation is illustrated by the following example.</p>
+<table id="style-attribute-ruby-example-2" role="example">
+<caption>Example Fragment &ndash; Complex Ruby</caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+&lt;span&gt;
+  &lt;span <phrase role="strong">tts:ruby="container"</phrase>&gt;
+    &lt;span <phrase role="strong">tts:ruby="baseContainer"</phrase>&gt;
+      &lt;span <phrase role="strong">tts:ruby="base"</phrase>&gt;&#x6771;&#x5357;&lt;/span&gt;
+    &lt;/span&gt;
+    &lt;span <phrase role="strong">tts:ruby="textContainer"</phrase> tts:rubyPosition="before"&gt;
+      &lt;span <phrase role="strong">tts:ruby="text"</phrase>&gt;&#x3068;&#x3046;&#x306A;&#x3093;&lt;/span&gt;
+    &lt;/span&gt;
+    &lt;span <phrase role="strong">tts:ruby="textContainer"</phrase> tts:rubyPosition="after"&gt;
+      &lt;span <phrase role="strong">tts:ruby="text"</phrase>&gt;&#x305F;&#x3064;&#x307F;&lt;/span&gt;
+    &lt;/span&gt;
+  &lt;/span&gt;
+  &lt;span&gt;&#x306E;&#x65B9;&#x89D2;&lt;/span&gt;
+&lt;/span&gt;
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<p></p>
+<table id="style-attribute-ruby-example-2-images" role="example-images">
+<caption>Example Rendition &ndash; Complex Ruby</caption>
+<tbody>
+<tr>
+<td><graphic source="images/ruby_2.png" alt="TTML ruby style property"/></td>
+</tr>
+</tbody>
+</table>
+<note role="derivation">
+<p>The semantics of the style property
+represented by this attribute are based upon that defined by <bibref ref="ruby"/> and <bibref ref="cssruby"/>. See also
+<bibref ref="jlreq"/>, &sect;3.3, for further information.</p>
+</note>
+</div3>
+<div3 id="style-attribute-rubyAlign">
+<head>tts:rubyAlign</head>
+<p>The <att>tts:rubyAlign</att> attribute is used to specify the position of ruby text within the inline area generated by the ruby text container annotation.</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 <loc href="#content-vocabulary-span"><el>span</el></loc> elements on which the computed value of the
+<att>tts:ruby</att> style property is either <code>textContainer</code> or <code>text</code>.</p>
+<table id="style-property-details-rubyAlign" role="common">
+<col width="25%"/>
+<col/>
+<tbody>
+<tr>
+<td><emph>Values:</emph></td>
+<td>
+<code>start</code> |
+<code>center</code> |
+<code>spaceBetween</code> |
+<code>spaceAround</code>
+</td>
+</tr>
+<tr>
+<td><emph>Initial:</emph></td>
+<td><code>spaceAround</code></td>
+</tr>
+<tr>
+<td><emph>Applies to:</emph></td>
+<td>
+<emph>see prose (above)</emph>
+</td>
+</tr>
+<tr>
+<td><emph>Inherited:</emph></td>
+<td>yes</td>
+</tr>
+<tr>
+<td><emph>Percentages:</emph></td>
+<td>N/A</td>
+</tr>
+<tr>
+<td><emph>Animatable:</emph></td>
+<td>discrete</td>
+</tr>
+</tbody>
+</table>
+<p></p>
+<p>If the value of this attribute is <code>start</code>, then the start edge of the first glyph area descendant of an inline area generated from a ruby text container
+or ruby text annotation is aligned to the start edge of that inline area.
+If the value is <code>center</code>, then excess whitespace
+is equally distributed before and after the first and last glyphs, respectively.
+If the value is <code>spaceBetween</code>, then excess whitespace
+is equally distributed between each glyph area descendant.
+If the value is <code>spaceAround</code>, then excess whitespace
+is equally distributed before and after each glyph area descendant.</p>
+<p>If a computed value of the property associated with this attribute is not supported,
+then a <loc href="#terms-presentation-processor">presentation processor</loc> must use the value <code>spaceAround</code>.</p>
+<ednote>
+<name>Ruby Align Example</name>
+<date>2014-09-20</date>
+<edtext>Add example and example rendering of tts:rubyAlign.</edtext>
+</ednote>
+<note role="derivation">
+<p>The semantics of the style property
+represented by this attribute are based upon that defined by <bibref ref="cssruby"/>, &sect;4.3, and the examples and example
+renderings shown there apply.</p>
+</note>
+</div3>
+<div3 id="style-attribute-rubyPosition">
+<head>tts:rubyPosition</head>
+<p>The <att>tts:rubyPosition</att> attribute is used to specify the position of ruby text in the block progression dimension
+with respect to its associated ruby base.</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 <loc href="#content-vocabulary-span"><el>span</el></loc> elements on which the computed value of the
+<att>tts:ruby</att> style property is either <code>textContainer</code> or <code>text</code>.</p>
+<table id="style-property-details-rubyPosition" role="common">
+<col width="25%"/>
+<col/>
+<tbody>
+<tr>
+<td><emph>Values:</emph></td>
+<td>
+<code>before</code> |
+<code>after</code> |
+<code>interCharacter</code>
+</td>
+</tr>
+<tr>
+<td><emph>Initial:</emph></td>
+<td><code>before</code></td>
+</tr>
+<tr>
+<td><emph>Applies to:</emph></td>
+<td>
+<emph>see prose (above)</emph>
+</td>
+</tr>
+<tr>
+<td><emph>Inherited:</emph></td>
+<td>yes</td>
+</tr>
+<tr>
+<td><emph>Percentages:</emph></td>
+<td>N/A</td>
+</tr>
+<tr>
+<td><emph>Animatable:</emph></td>
+<td>discrete</td>
+</tr>
+</tbody>
+</table>
+<p></p>
+<p>If the value of this attribute is <code>before</code>, then an inline area generated from a ruby text container or ruby text annotation
+is placed before (prior to) the first edge in the block progression dimension of the inline area generated from an associated ruby base container or ruby base annotation.
+If the value is <code>after</code>, then an inline area generated from a ruby text container or ruby text annotation
+is placed after (subsequent to) the second edge in the block progression dimension of the inline area generated from an associated ruby base container or ruby base
+annotation.</p>
+<p>If the value of this attribute is <code>interCharacter</code>, then an inline area generated from a ruby text container or ruby text annotation is placed
+after the end edge in the inline progression dimension of the inline area generated from an associated ruby base container or ruby base annotation.</p>
+<p>The absolute position of the ruby text container or ruby text annotation is determined
+in accordance to the computed value of the <code>tts:writingMode</code> style property of the region into which the affected content is placed; in particular, the
+mappings defined enumerated by <specref ref="rubyPosition-semantics-mapping-table"/> apply as further defined by <bibref ref="cssruby"/>, &sect;4.1.</p>
+<p>If a computed value of the property associated with this attribute is not supported,
+then a <loc href="#terms-presentation-processor">presentation processor</loc> must use the value <code>before</code>.</p>
+<table id="rubyPosition-semantics-mapping-table" role="common">
+<caption>Table 8-2 &ndash; Ruby Position Semantics Mapping by Writing Mode</caption>
+<col width="20%"/>
+<col width="20%"/>
+<col width="20%"/>
+<col width="20%"/>
+<col width="20%"/>
+<col/>
+<tbody>
+<tr>
+<th>tts:rubyPosition</th>
+<th><code>lrtb</code></th>
+<th><code>rltb</code></th>
+<th><code>tbrl</code></th>
+<th><code>tblr</code></th>
+</tr>
+<tr>
+<td><code>before</code></td>
+<td><code>over</code></td>
+<td><code>over</code></td>
+<td><code>right</code></td>
+<td><code>left</code></td>
+</tr>
+<tr>
+<td><code>after</code></td>
+<td><code>under</code></td>
+<td><code>under</code></td>
+<td><code>left</code></td>
+<td><code>right</code></td>
+</tr>
+<tr>
+<td><code>interCharacter</code></td>
+<td><code>right</code></td>
+<td><code>left</code></td>
+<td><code>under</code></td>
+<td><code>under</code></td>
+</tr>
+</tbody>
+</table>
+<p></p>
+<ednote>
+<name>Ruby Position Example</name>
+<date>2014-09-20</date>
+<edtext>Add example and example rendering of tts:rubyPosition.</edtext>
+</ednote>
+<note role="derivation">
+<p>The semantics of the style property
+represented by this attribute are based upon that defined by <bibref ref="cssruby"/>, &sect;4.1, and the examples and example
+renderings shown there apply modulo the mappings defined above.</p>
+</note>
+</div3>
 <div3 id="style-attribute-showBackground">
 <head>tts:showBackground</head>
 <p>The <att>tts:showBackground</att> attribute is used to specify
@@ -7877,7 +8325,6 @@
 </note>
 </div3>
 </div2> <!-- styling-attribute-vocabulary -->
-
 <div2 id="styling-style-value-expressions">
 <head>Style Value Expressions</head>
 <p>Style property values include the use of the following expressions:</p>
@@ -7933,7 +8380,6 @@
 the computed value, then the value most distant from 0, i.e., the greatest opacity, is used.</p>
 </note>
 </div3>
-
 <div3 id="style-value-border-color">
 <head>&lt;border-color&gt;</head>
 <p>A &lt;border-color&gt; expression is used to express the color of one
@@ -7952,7 +8398,6 @@
 </tbody>
 </table>
 </div3>
-
 <div3 id="style-value-border-style">
 <head>&lt;border-style&gt;</head>
 <p>A &lt;border-style&gt; expression is used to express the style of one
@@ -7980,7 +8425,6 @@
 it must be interpreted as if a style of <code>solid</code> were specified; however, an implementation that
 supports borders must minimally support the <code>none</code> and <code>solid</code> values.</p>
 </div3>
-
 <div3 id="style-value-border-width">
 <head>&lt;border-width&gt;</head>
 <p>A &lt;border-width&gt; expression is used to express the width of one
@@ -8007,7 +8451,6 @@
 <p>If a border width is expressed as a <loc href="#style-value-length">&lt;length&gt;</loc>,
 then it must not take the form of a percentage value; i.e., it must take the form of a scalar value.</p>
 </div3>
-
 <div3 id="style-value-color">
 <head>&lt;color&gt;</head>
 <p>A &lt;color&gt; expression is used to specify a named color, exact RGB color triple,
@@ -8027,19 +8470,14 @@
   | "rgb" "(" r-value "," g-value "," b-value ")"
   | "rgba" "(" r-value "," g-value "," b-value "," a-value ")"
   | <loc href="#style-value-namedColor">&lt;namedColor&gt;</loc>
-
 rrggbb
   :  <loc href="#style-value-hexDigit">&lt;hexDigit&gt;</loc>{6}
-
 rrggbbaa
   :  <loc href="#style-value-hexDigit">&lt;hexDigit&gt;</loc>{8}
-
 r-value | g-value | b-value | a-value
   : component-value
-
 component-value
   : non-negative-integer                    // valid range: [0,255]
-
 non-negative-integer
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>+
 </eg>
@@ -8108,39 +8546,29 @@
 &lt;familyName&gt;
   : 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
   : '\\' <emph>char</emph>
-
 quoted-string
   : double-quoted-string
   | single-quoted-string
-
 double-quoted-string
   : '"' ( [^"\\] | escape )+ '"'
-
 single-quoted-string
   : "'" ( [^'\\] | escape )+ "'"
 </eg>
@@ -8279,29 +8707,21 @@
 &lt;length&gt;
   : scalar
   | percentage
-
 scalar
   : number units
-
 percentage
   : number "%"
-
 sign
   : "+" | "-"
-
 number
   : sign? non-negative-number
-
 non-negative-number
   : non-negative-integer
   | non-negative-real
-
 non-negative-integer
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>+
-
 non-negative-real
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>* "." <loc href="#style-value-digit">&lt;digit&gt;</loc>+
-
 units
   : "px"
   | "em"
@@ -8401,7 +8821,6 @@
 </note>
 </div3>
 </div2> <!-- styling-style-value-expressions -->
-
 <div2 id="semantics-style-resolution">
 <head>Style Resolution</head>
 <p>This section defines the semantics of style resolution in terms of
@@ -8590,14 +9009,8 @@
 <ulist>
 <item><p><loc href="#semantics-style-inheritance-content">content style inheritance</loc></p></item>
 <item><p><loc href="#semantics-style-inheritance-content">region style inheritance</loc></p></item>
-</ulist>
-<ednote>
-<name>Layout Style Inheritance</name>
-<date>2013-09-05</date>
-<edtext>Regions should be able to inherit styles from a common ancestor in order to prevent
-having to full populate region styles. <loc href="https://www.w3.org/AudioVideo/TT/tracker/issues/277">Issue 277</loc> proposes
-inheritance from the layout element.</edtext>
-</ednote>
+<item><p><loc href="#semantics-style-inheritance-content">root style inheritance</loc></p></item>
+</ulist>
 <p>For the purpose of determining inherited styles, the element hierarchy of
 an intermediate synchronic document form of a <loc href="#terms-document-instance">document instance</loc> must be used, where
 such intermediate forms are defined by <specref ref="semantics-region-layout-step-1"/>.</p>
@@ -8613,14 +9026,10 @@
 if a style property is not associated with a <loc href="#terms-content-element">content element</loc> (or
 an anonymous span) and the style property is designated as
 inheritable.</p>
-<note role="clarification">
-<p>The <el>tt</el> element is not a <loc href="#terms-content-element">content element</loc>;
-consequently, the <el>body</el> element is the outermost element from which content style inheritance occurs.</p>
-</note>
 <p>If a style property is determined to require inheritance, then the inherited value must
 be the value of the same named style property in the computed
 style set of the
-element's immediate ancestor element
+element's nearest ancestor element that defines the property
 within the applicable intermediate synchronic document.</p>
 <table id="style-inheritance-example-2" role="example">
 <caption>Example &ndash; Content Style Inheritance</caption>
@@ -8653,14 +9062,11 @@
 <head>Region Style Inheritance</head>
 <p>Style properties are inherited from a <loc href="#layout-vocabulary-region">region</loc> element in the following case:</p>
 <olist>
-<item><p>if a style property <emph>P</emph> is not associated with
+<item><p>if an inheritable style property <emph>P</emph> is not associated with
 a <loc href="#terms-content-element">content element</loc>
-or an anonymous span <emph>E</emph> and the style
-property is designated as inheritable, and</p></item> <item><p>if that
-style property <emph>P</emph> is in the computed style
-set of region
-<emph>R</emph>,
-and</p></item>
+or an anonymous span <emph>E</emph>, and</p></item>
+<item><p>if that style property <emph>P</emph> is in the computed style
+set of region <emph>R</emph>, and</p></item>
 <item><p>if that element <emph>E</emph> is flowed into (presented within) region
 <emph>R</emph>.</p></item>
 </olist>
@@ -8688,6 +9094,46 @@
 element into which the <el>p</el> element is flowed (presented).</p>
 </note>
 </div4>
+<div4 id="semantics-style-inheritance-root">
+<head>Root Style Inheritance</head>
+<p>Style properties are inherited from the root <loc href="#document-structure-vocabulary-tt">tt</loc> element in the following case:</p>
+<olist>
+<item><p>if an inheritable style property <emph>P</emph> is not associated with
+a <loc href="#layout-vocabular-region"><el>region</el></loc> element, and</p></item>
+<item><p>if that
+style property <emph>P</emph> is in the computed style
+set of the root <loc href="#document-structure-vocabulary-tt">tt</loc> element.</p></item>
+</olist>
+<note role="motivation">
+<p>Root style inheritance provides a mechanism by means of which <el>region</el> elements
+can inherit a common style rather than repeating the specification of the style on each
+<el>region</el> element.</p>
+</note>
+<table id="style-inheritance-example-4" role="example">
+<caption>Example &ndash; Root Style Inheritance</caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+&lt;tt <phrase role="strong">tts:color="yellow"</phrase>&gt;
+...
+&lt;region xml:id="r1" <phrase role="strong">tts:fontFamily="monospaceSerif"</phrase>/&gt;
+...
+&lt;p region="r1"&gt;Yellow Monospace&lt;/p&gt;
+...
+&lt;/tt&gt;
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<note role="explanation">
+<p>In the above example, the <el>region</el> element inherits the
+<att>tts:color</att> style specified on the <el>tt</el> element, which,
+along with the <att>tts:fontFamily</att> style specified on the <el>region</el>
+element, are inherited by <el>p</el> element when selected into the region.</p>
+</note>
+</div4>
 </div3>
 <div3 id="semantics-style-resolution-value-categories">
 <head>Style Resolution Value Categories</head>
@@ -8936,30 +9382,56 @@
 merge the specified style set of <emph>A</emph>,
 <emph>SSS(A)</emph>, into the specified style set of <emph>E</emph>, <emph>SSS(E)</emph>;</p></item>
 <item>
-<p><phrase role="strong">[implicit inheritance]</phrase> if the
-element type of <emph>E</emph> is not the animation element type <el>set</el>
-or the styling element type <el>style</el>,
-then for each inheritable style property
-<emph>P<sub>INH</sub></emph> in the set of style properties defined
+<p><phrase role="strong">[implicit inheritance and initial value fallback]</phrase> if the
+element type of <emph>E</emph> is not animation element type <el>animate</el> or <el>set</el>
+and is not styling element type <el>style</el>,
+then for each style property
+<emph>P</emph> in the set of style properties defined
 above in <specref ref="styling-attribute-vocabulary"/>, perform the
 following ordered sub-steps:</p>
 <olist>
-<item><p>if <emph>P<sub>INH</sub></emph> is present in the specified
+<item>
+<p>if <emph>P</emph> is present in the specified
 style set of <emph>E</emph>, <emph>SSS(E)</emph>, then continue to the
-next inheritable style property;</p></item>
-<item><p>if the element type of <emph>E</emph> is the layout element
-type <el>region</el>, then set <emph>P&prime;</emph> to the initial value of
+next style property;</p>
+</item>
+<item>
+<p>if <emph>P</emph> is defined to be inheritable and <emph>E</emph> is
+not the <loc href="#document-structure-vocabulary-tt"><el>tt</el></loc> element, then perform the following:</p>
+<ulist>
+<item>
+<p>if <emph>E</emph> is not a
+<loc href="#styling-vocabulary-style"><el>style</el></loc>,
+<loc href="#animation-vocabulary-animate"><el>animate</el></loc>, or
+<loc href="#animation-vocabulary-set"><el>set</el></loc> element,
+then set <emph>P&prime;</emph> to the result of
+looking up the value of <emph>P</emph> in the computed style set of
+the nearest ancestor element of <emph>E</emph>, <emph>NEAREST-ANCESTOR(E)</emph>, such that
+<emph>CSS(NEAREST-ANCESTOR(E))</emph> contains a definition of <emph>P</emph>;</p>
+</item>
+</ulist>
+</item>
+<item>
+<p>otherwise (<emph>P</emph> is not inheritable or <emph>E</emph> is
+the <loc href="#document-structure-vocabulary-tt"><el>tt</el></loc> element), perform the following:</p>
+<ulist>
+<item><p>set <emph>P&prime;</emph> to the initial value of
 property <emph>P</emph>, where the initial value of a property is
-determined according to the specific property definition found above
+determined as follows:</p>
+<olist>
+<item><p>if an <loc href="#styling-vocabulary-initial"><el>initial</el></loc>
+element defines the initial value for <emph>P</emph>, then use that value;</p></item>
+<item><p>otherwise, use the initial value specified by the property definition of <emph>P</emph> found above
 in <specref ref="styling-attribute-vocabulary"/>;</p></item>
-<item><p>if the element type of <emph>E</emph> is a <loc href="#terms-content-element">content element</loc>
-type or anonymous span, then set <emph>P&prime;</emph> to the result of
-looking up the value of <emph>P</emph> in the computed style set of
-the immediate ancestor element of <emph>E</emph>, i.e.,
-<emph>CSS(PARENT(E))</emph>;</p></item>
-<item><p>if the value of <emph>P&prime;</emph> is not undefined, then merge
+</olist>
+</item>
+</ulist>
+</item>
+<item>
+<p>if the value of <emph>P&prime;</emph> is not undefined, then merge
 <emph>P&prime;</emph> into the specified style set of <emph>E</emph>,
-<emph>SSS(E)</emph>.</p></item>
+<emph>SSS(E)</emph>.</p>
+</item>
 </olist>
 </item>
 </olist>
@@ -8980,7 +9452,7 @@
 initialize <emph>CSS(E)</emph> to a (deep) copy of
 <emph>SSS(E)</emph>;</p></item>
 <item><p><phrase role="strong">[filter]</phrase> if
-<emph>E</emph> is a <el>set</el> or <el>style</el> element, then return
+<emph>E</emph> is an <el>animate</el>, <el>set</el>, or <el>style</el> element, then return
 <emph>CSS(E)</emph> as the resulting computed style set without
 further resolution; otherwise, continue with the next rule;</p></item>
 <item>
@@ -8997,30 +9469,40 @@
 </olist>
 <note role="explanation">
 <p>As a result of the filtering rule above, the computed style set of
-a <el>set</el> or <el>style</el> element includes only specified values, in which case
+an <el>animate</el>, <el>set</el>, or <el>style</el> element includes only specified values, in which case
 relative value expressions remain relative; consequently, the
 resolution of relative value expressions (that may be assigned by
 means of referential style association) always takes place in the
 context of a layout or <loc href="#terms-content-element">content element</loc> which has a presentation
 context, and not in the non-presentation, declaration context
-of a <el>set</el> element or a referentiable <el>style</el> element.</p>
+of an <el>animate</el>, <el>set</el>, or referable <el>style</el> element.</p>
 </note>
 </div4>
 <div4 id="semantics-style-resolution-process-overall">
 <head>Style Resolution Process</head>
 <p>The top-level style resolution process is defined as follows: using
-a preorder traversal of each element and anonymous span,
+a preorder traversal of each element and <emph>anonymous span</emph>,
 <emph>E</emph>, of an intermediate synchronic document,
 <emph>DOC<sub>inter</sub></emph>, perform the following ordered
 sub-steps:</p>
 <olist>
-<item><p><phrase role="strong">[filter]</phrase> if the element type
-of <emph>E</emph> is not the styling element type <el>style</el>, is
-not the layout element type <el>region</el>, is not the animation
-element type <el>set</el>, and is not one of the
-<loc href="#terms-content-element">content element</loc> types <el>body</el>, <el>div</el>, <el>p</el>,
-<el>span</el>, <el>br</el>, or anonymous span, then continue to the
-next element in the preorder traversal;</p></item>
+<item><p><phrase role="strong">[filter]</phrase> if <emph>E</emph>
+is not one of the following, then continue to the next element in the preorder traversal, i.e.,
+do not perform the subsequent step below on <emph>E</emph>:</p>
+<ulist>
+<item><p><loc href="#document-structure-vocabulary-tt"><el>tt</el></loc></p></item>
+<item><p><loc href="#styling-vocabulary-style"><el>style</el></loc></p></item>
+<item><p><loc href="#layout-vocabulary-region"><el>region</el></loc></p></item>
+<item><p><loc href="#document-structure-vocabulary-body"><el>body</el></loc></p></item>
+<item><p><loc href="#content-vocabulary-body"><el>div</el></loc></p></item>
+<item><p><loc href="#content-vocabulary-body"><el>p</el></loc></p></item>
+<item><p><loc href="#content-vocabulary-body"><el>span</el></loc></p></item>
+<item><p><loc href="#content-vocabulary-body"><el>br</el></loc></p></item>
+<item><p><loc href="#animation-vocabulary-animate"><el>animate</el></loc></p></item>
+<item><p><loc href="#animation-vocabulary-set"><el>set</el></loc></p></item>
+<item><p><emph>anonymous span</emph></p></item>
+</ulist>
+</item>
 <item><p> <phrase role="strong">[resolve computed styles]</phrase>
 determine (obtain) the computed style set <emph>CSS</emph> of
 <emph>E</emph>, namely, <emph>CSS(E)</emph>, in accordance with
@@ -9030,7 +9512,6 @@
 </div3>
 </div2> <!-- semantics-style-resolution -->
 </div1> <!-- styling -->
-
 <div1 id="layout">
 <head>Layout</head>
 <p>This section specifies the <emph>layout</emph> matter of the core
@@ -9192,7 +9673,6 @@
 (associated with) the region.</p>
 </div3>
 </div2> <!-- layout-element-vocabulary -->
-
 <div2 id="layout-attribute-vocabulary">
 <head>Layout Attribute Vocabulary</head>
 <p>This section defines the <specref ref="layout-attribute-region"/> attribute used with <loc href="#terms-content-element">content elements</loc>.</p>
@@ -9219,7 +9699,6 @@
 </note>
 </div3>
 </div2> <!-- layout-attribute-vocabulary -->
-
 <div2 id="semantics-region-layout">
 <head>Region Layout and Presentation</head>
 <p>This section defines the semantics of region layout and
@@ -9316,13 +9795,11 @@
 the latter as an <emph>explicit inline region specification</emph>; furthermore, the former is considered
 to be a syntactic shorthand for the latter, and is processed by converting it into the latter as
 described below.</p>
-
 <p>Inline regions are processed in accordance with the procedure
 <phrase role="strong"><loc href="#procedure-process-inline-regions">[process inline regions]</loc></phrase>, which
 entails first generating implied inline regions, and then generating out-of-line regions that correspond with implied
 or explicit inline regions. This latter procedure additionally binds content elements associated with inline regions
 to the corresponding generated out-of-line regions.</p>
-
 <note role="elaboration">
 <p>A <loc href="#terms-content-element">content element</loc> can only be associated with a single
 <loc href="#terms-region">region</loc>. Consequently, if a <loc href="#terms-content-element">content element</loc>
@@ -9332,7 +9809,6 @@
 both an <emph>implied inline region specification</emph> and an <emph>explicit inline region specification</emph>,
 then the former is ignored in favor of the latter.</p>
 </note>
-
 <glist>
 <gitem id="procedure-process-inline-regions">
 <label>[process inline regions]</label>
@@ -9478,9 +9954,7 @@
 </def>
 </gitem>
 </glist>
-
 <p>The use of an <emph>implied inline region specification</emph> and the resulting generated inline region is shown by the following two example documents.</p>
-
 <table id="semantics-inline-region-input-example-1-implied" role="example">
 <caption>Example &ndash; Implied Inline Region Specification</caption>
 <tbody>
@@ -9500,7 +9974,6 @@
 </tr>
 </tbody>
 </table>
-
 <p></p>
 <table id="semantics-generated-out-of-line-region-example-1-implied" role="example">
 <caption>Example &ndash; Generated Inline Region</caption>
@@ -9522,11 +9995,9 @@
 </tr>
 </tbody>
 </table>
-
 <p>The use of an <emph>explicit inline region specification</emph> or a generated inline region that derives from
 an <emph>implicit inline region specification</emph>
 and the resulting generated out-of-line region is shown by the following two example documents.</p>
-
 <table id="semantics-inline-region-input-example-2-explicit" role="example">
 <caption>Example &ndash; Explicit or Generated Inline Region Specification</caption>
 <tbody>
@@ -9547,7 +10018,6 @@
 </tr>
 </tbody>
 </table>
-
 <p></p>
 <table id="semantics-generated-out-of-line-region-example-2-explicit" role="example">
 <caption>Example &ndash; Generated Out-of-line Region</caption>
@@ -9575,6 +10045,11 @@
 </div3>
 <div3 id="semantics-region-layout-step-1">
 <head>Intermediate Synchronic Document Construction</head>
+<ednote>
+<name>Use Formalized ISD</name>
+<date>2014-09-22</date>
+<edtext>Revise in order to take into account new formalization of ISD structure and semantics (Appendix C).</edtext>
+</ednote>
 <p>For the purposes of performing presentation processing, the active time
 duration of a <loc href="#terms-document-instance">document instance</loc> is divided into a sequence of time coordinates where at
 each time coordinate, some element becomes temporally active or inactive,
@@ -9932,7 +10407,6 @@
 </table>
 </div3>
 </div2> <!-- semantics-region-layout -->
-
 <div2 id="semantics-line-layout">
 <head>Line Layout</head>
 <p>If a profile that applies to a <loc href="#terms-document-instance">document instance</loc>
@@ -9945,7 +10419,6 @@
 line layout on the content of the <loc href="#terms-document-instance">document instance</loc>.</p>
 </div2> <!-- semantics-line-layout -->
 </div1> <!-- layout -->
-
 <div1 id="timing">
 <head>Timing</head>
 <p>This section specifies the <emph>timing</emph> matter of the core
@@ -9958,7 +10431,6 @@
 <p>No timing related element vocabulary is defined for use in the core
 vocabulary catalog.</p>
 </div2> <!-- timing-element-vocabulary -->
-
 <div2 id="timing-attribute-vocabulary">
 <head>Timing Attribute Vocabulary</head>
 <p>This section defines the following basic timing attributes for use with timed elements:</p>
@@ -10082,7 +10554,6 @@
 while taking into account any overriding semantics defined by this specification.</p>
 </div3>
 </div2> <!-- timing-attribute-vocabulary -->
-
 <div2 id="timing-time-value-expressions">
 <head>Time Value Expressions</head>
 <p>Timing attribute values include the use of the following expressions:</p>
@@ -10095,7 +10566,6 @@
 some time base, where the applicable time base is determined by the
 <att>ttp:timeBase</att> parameter, and where the semantics defined
 by <specref ref="time-expression-semantics"/> apply.</p>
-
 <note role="example">
 <p>See
 <specref ref="parameter-attribute-frameRate"/>,
@@ -10113,33 +10583,24 @@
 &lt;timeExpression&gt;
   : clock-time
   | offset-time
-
 clock-time
   : hours ":" minutes ":" seconds ( fraction | ":" frames ( "." sub-frames )? )?
-
 offset-time
-  : time-count fraction? metric
-
+  : time-count fraction? metric?
 hours
   : <loc href="#style-value-digit">&lt;digit&gt;</loc> <loc href="#style-value-digit">&lt;digit&gt;</loc>
   | <loc href="#style-value-digit">&lt;digit&gt;</loc> <loc href="#style-value-digit">&lt;digit&gt;</loc> <loc href="#style-value-digit">&lt;digit&gt;</loc>+
-
 minutes | seconds
   : <loc href="#style-value-digit">&lt;digit&gt;</loc> <loc href="#style-value-digit">&lt;digit&gt;</loc>
-
 frames
   : <loc href="#style-value-digit">&lt;digit&gt;</loc> <loc href="#style-value-digit">&lt;digit&gt;</loc>
   | <loc href="#style-value-digit">&lt;digit&gt;</loc> <loc href="#style-value-digit">&lt;digit&gt;</loc> <loc href="#style-value-digit">&lt;digit&gt;</loc>+
-
 sub-frames
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>+
-
 fraction
   : "." <loc href="#style-value-digit">&lt;digit&gt;</loc>+
-
 time-count
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>+
-
 metric
   : "h"                 // hours
   | "m"                 // minutes
@@ -10173,9 +10634,11 @@
 ref="parameter-attribute-subFrameRate"/>.
 It is considered an error if a <emph>sub-frames</emph> term is specified
 when the <code>clock</code> time base applies.</p>
+<p>If a &lt;timeExpression&gt; is expressed in terms of a
+<emph>offset-time</emph> and no <emph>metric</emph> is specified, then it is to be treated as
+if a metric of <code>s</code> (seconds) were specified.</p>
 </div3>
 </div2> <!-- timing-time-value-expressions -->
-
 <div2 id="timing-time-intervals">
 <head>Time Intervals</head>
 <p>The semantics of time containment, durations, and intervals defined by
@@ -10225,7 +10688,6 @@
 </ulist>
 </div2> <!-- timing-time-intervals -->
 </div1> <!-- timing -->
-
 <div1 id="animation">
 <head>Animation</head>
 <p>This section specifies the <emph>animation</emph> matter of the
@@ -10374,7 +10836,6 @@
 with Continuously Varying Colors!" is continuously animated from yellow, to red, to green, to
 red, then back to yellow over a 5 second period.</p>
 </note>
-
 <p>An example of using the <el>animate</el> element to animate region
 styling is illustrated below:</p>
 <table id="animation-vocabulary-animate-example-2" role="example">
@@ -10514,7 +10975,6 @@
 with Flashing Colors!" is animated from yellow, to red, to green, to
 red, then back to yellow over a 5 second period.</p>
 </note>
-
 <p>An example of using the <el>set</el> element to animate region
 styling is illustrated below:</p>
 <table id="animation-vocabulary-set-example-2" role="example">
@@ -10717,24 +11177,18 @@
 <eg xml:space="preserve">
 &lt;keySplines&gt;
   : control [ lwsp? ";" lwsp? control ]*
-
 control
   : x1 comma? y1 comma? x2 comma? y2
-
 x1, x2, y1, y2
   : coordinate
-
 coordinate                                // 0 &ge; <emph>value</emph> &ge; 1
   : whole
   | whole "." fraction
   | "." fraction
-
 whole, fraction
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>+
-
 comma
   : ","
-
 lwsp
   : ( ' ' | '\t' | '\n' | '\r' )+
 </eg>
@@ -10758,15 +11212,12 @@
 <eg xml:space="preserve">
 &lt;keyTimes&gt;
   : time [ lwsp? ";" lwsp? time ]*
-
 time                                // 0 &ge; <emph>value</emph> &ge; 1
   : whole
   | whole "." fraction
   | "." fraction
-
 whole, fraction
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>+
-
 lwsp
   : ( ' ' | '\t' | '\n' | '\r' )+
 </eg>
@@ -10789,7 +11240,6 @@
 &lt;repeatCount&gt;
   : count
   | "indefinite"
-
 count:
   : <loc href="#style-value-digit">&lt;digit&gt;</loc>+                       // <emph>value</emph> > 0
 </eg>
@@ -10802,7 +11252,6 @@
 </div3>
 </div2> <!-- animation-value-expressions -->
 </div1> <!-- animation -->
-
 <div1 id="metadata">
 <head>Metadata</head>
 <p>This section specifies the <emph>metadata</emph> matter of the core
@@ -10814,14 +11263,13 @@
 specification for standardized use in a <loc href="#terms-document-instance">document instance</loc>, 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>
-
 <div2 id="metadata-element-vocabulary">
 <head>Metadata Element Vocabulary</head>
 <p>The <specref ref="metadata-vocabulary-metadata"/> 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 metadata that is expected to be commonly
-used in a <loc href="#terms-document-instance">document instancea</loc>:
+used in a <loc href="#terms-document-instance">document instance</loc>:
 </p>
 <ulist>
 <item><p><specref ref="metadata-vocabulary-title"/></p></item>
@@ -10910,7 +11358,6 @@
 </tbody>
 </table>
 <p></p>
-
 <p>The use of metadata attribute items is illustrated by the following example.</p>
 <table id="metadata-vocabulary-metadata-example-3" role="example">
 <caption>Example Fragment &ndash; Foreign Metadata Attribute Items</caption>
@@ -11110,7 +11557,6 @@
 <tr>
 <td>
 <eg xml:space="preserve">
-
 &lt;tt xml:lang="en" xmlns="http://www.w3.org/ns/ttml" xmlns:ttm="http://www.w3.org/ns/ttml#metadata"&gt;
   &lt;head&gt;
     <phrase role="strong">&lt;ttm:agent xml:id="connery" type="person"&gt;</phrase>
@@ -11218,7 +11664,6 @@
 <specref ref="metadata-vocabulary-agent-example-1"/>.</p>
 </div3>
 </div2> <!-- metadata-element-vocabulary -->
-
 <div2 id="metadata-attribute-vocabulary">
 <head>Metadata Attribute Vocabulary</head>
 <p>This section specifies the following attributes in the TT Metadata Namespace
@@ -11266,7 +11711,6 @@
 <eg xml:space="preserve">
 ttm:role
   role ( <emph>S</emph> role )*
-
 role
   : "action"
   | "caption"
@@ -11286,10 +11730,8 @@
   | "title"
   | "transcription"
   | extension-role
-
 extension-role
   : "x-" token-char+
-
 token-char
   : { XML NameChar }    // XML 1.1 Production [4a]
 </eg>
@@ -11316,9 +11758,7 @@
 </div3>
 </div2> <!-- metadata-attribute-vocabulary -->
 </div1> <!-- metadata -->
-
 </body>
-
 <back>
 <div1 id="reduced-infoset">
 <head>Reduced XML Infoset</head>
@@ -11399,14 +11839,297 @@
 is defined by <specref ref="conformance-content"/>.</p>
 </div2>
 </div1>
-<inform-div1 id="media-types-registration">
-<head>Media Type Registration</head>
-<note>
-<p>The information from this appendix has been removed since media type
-registration has already occurred. This section is retained in its empty form
-in order to prevent appendix renumbering.</p>
-</note>
-</inform-div1>
+<div1 id="isd">
+<head>Intermediate Synchronic Document Syntax</head>
+<p><emph>This appendix is normative.</emph></p>
+<p>This appendix specifies the syntactic elements and structure of a TTML Intermediate Synchronic Document (ISD) Sequence and its
+constituent TTML Intermediate Synchronic Document (ISD) instances. An ISD instance may be represented as a standalone document instance or
+in a collection represented as an ISD Sequence instance.</p>
+<p>All ISD related vocabulary is defined in the TTML ISD Namespace, defined here as <code>http://www.w3.org/ns/ttml#isd</code>,
+where the recommended prefix is <code>isd</code>.</p>
+<p>A TTML <loc href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</loc>, in short, an <emph>ISD</emph> or <emph>ISD instance</emph>,
+represents a discrete, temporally non-overlapping interval, an <emph>ISD interval</emph>,
+of a source TTML document where, except for non-discrete animation, all content, styling, and layout information remains static within that interval.
+In particular, the timing hierarchy of a TTML document is flattened and then sub-divided into temporally non-overlapping intervals, where each such
+interval defines a static view of the source TTML document within that interval, and where that static view is represented as an ISD instance.
+A concrete, standalone instance of a TTML
+<loc href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</loc> must specify an
+<loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> element as its root document element. When an instance of a
+<loc href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</loc> is included in a
+<loc href="#terms-intermediate-synchronic-document-sequence">Intermediate Synchronic Document Sequence</loc> instance, then the ISD instance is represented
+by an <loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> child element of the root 
+<loc href="#isd-vocabulary-sequence"><el>isd:sequence</el></loc> element.</p>
+<note role="elaboration">
+<p>An ISD instance may contain one or more animate elements that denote continuous animation within the associated interval. Continuously animated styles are sub-divided across
+ISD interval boundaries such that their step-wise concatenation expresses an equivalent continuous animation over any intersecting ISD interval(s).</p>
+</note>
+<p>A TTML <loc href="#terms-intermediate-synchronic-document-sequence">Intermediate Synchronic Document Sequence</loc> represents a collection
+of temporally non-overlapping <loc href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</loc> instances ordered according
+to their begin times. A concrete instance of a TTML
+<loc href="#terms-intermediate-synchronic-document-sequence">Intermediate Synchronic Document Sequence</loc> must specify an
+<loc href="#isd-vocabulary-sequence"><el>isd:sequence</el></loc> element as its root document element.</p>
+<div2 id="isd-vocabulary">
+<head>ISD Vocabulary</head>
+<div3 id="isd-vocabulary-sequence">
+<head>isd:sequence</head>
+<p>The <el>isd:sequence</el> element serves as the root document element of an <loc href="#terms-intermediate-synchronic-document-sequence">Intermediate
+Synchronic Document Sequence</loc>  document.</p>
+<p>The <el>isd:sequence</el> element accepts as its children zero or more elements in the
+<loc href="#element-vocab-group-metadata"><code>Metadata.class</code></loc> element group,
+followed by zero or one <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc> element,
+followed by zero or more <loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> elements.</p>
+<p>Child <el>isd:isd</el> elements must be ordered in accordance to the media time equivalent of their
+begin time; furthermore, the temporal intervals of any two child <loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> elements must not overlap (in time).</p>
+<table id="elt-syntax-isd-sequence" role="syntax">
+<caption>XML Representation &ndash; Element Information Item: isd:sequence</caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+&lt;isd:sequence
+  size = xsd:nonNegativeInteger
+  version = xsd:positiveInteger
+  <loc href="#content-attribute-lang"><phrase role="reqattr">xml:lang</phrase></loc> = string
+  {<emph>any attribute in the <loc href="#isd-parameter-attribute-set">ISD Parameter Attribute Set</loc></emph>}&gt;
+  {<emph>any attribute not in default or any TT namespace</emph>}&gt;
+  <emph>Content:</emph> <loc href="#element-vocab-group-metadata">Metadata.class</loc>*, <loc href="#parameter-vocabulary-profile">ttp:profile</loc>?, <loc href="#isd-vocabulary-isd">isd:isd</loc>*
+&lt;/isd:sequence&gt;
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<p>If the <att>size</att> attribute is specified, then it must be a non-negative integer corresponding to the number of
+<loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> child elements.
+If not specified, then the size must be considered to be <emph>indefinite</emph>, unless and until the
+<loc href="#isd-vocabulary-sequence"><el>isd:sequence</el></loc> element is terminated, in which case the size
+may be determined by inspection.</p>
+<note role="elaboration">
+<p>The <att>size</att> attribute would normally be omitted in the case of real time captioning.</p>
+</note>
+<p>If the <att>version</att> attribute is specified, then it must be a positive integer corresponding to the version of this
+<loc href="#terms-intermediate-synchronic-document-syntax">Intermediate Synchronic Document Syntax</loc> specification used in authoring
+the ISD sequence document. If specified, the numeric value must be greater than or equal to two (2). If not specified, then the version must be
+consider to be equal to two (2). The version associated with this
+<loc href="#terms-intermediate-synchronic-document-sequence-syntax">Intermediate Synchronic Document Sequence Syntax</loc> specification is two (2).</p>
+<note role="elaboration">
+<p>The ISD abstraction referred to or implied by <bibref ref="ttml1"/> &sect;9.3.2 was not concretely defined by that specification. Here we reserve version one (1)
+for informal discussion of that earlier abstraction and its various (non-standardized) realizations.</p>
+</note>
+<p>An <loc href="#content-attribute-lang"><att>xml:lang</att></loc> attribute must be specified on the
+<loc href="#isd-vocabulary-sequence"><el>isd:sequence</el></loc> element.
+If its value is empty, it signifies that there is no default language that applies
+to the content within the <loc href="#terms-intermediate-synchronic-document-sequence">Intermediate Synchronic Document Sequence</loc>. Otherwise,
+the specified value denotes the default language that applies to each constituent
+<loc href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</loc>.</p>
+<p>One or more parameter properties may be specified from the restricted parameter attribute set enumerated in <specref ref="isd-parameter-attribute-set"/>.
+If specified, then they apply globally to each constituent <loc href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</loc>.</p>
+<p>If a child <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc> element is present,
+then that <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc> element must satisfy the following constraints:</p>
+<ulist>
+<item><p>no <att>combine</att> attribute is specified;</p></item>
+<item><p>no <att>designator</att> attribute is specified;</p></item>
+<item><p>no <att>type</att> attribute is specified;</p></item>
+<item><p>no <att>use</att> attribute is specified;</p></item>
+<item><p>no descendant element is a <el>ttp:profile</el> element;</p></item>
+<item><p>no descendant <el>ttp:feature</el> element specifies a <att>value</att> attribute with the value <code>prohibited</code>;</p></item>
+<item><p>no descendant <el>ttp:extension</el> element specifies a <att>value</att> attribute with the value <code>prohibited</code>.</p></item>
+</ulist>
+<p>Furthermore, such a child <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc> element must specify a profile that is equivalent to the combined
+<loc href="#terms-processor-profile">processor profile</loc> of the source TTML document having fetched all externally referenced profile documents.</p>
+<note role="elaboration">
+<p>The intent of permitting a single <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc> to be specified in an
+<loc href="#isd-vocabulary-sequence"><el>isd:sequence</el></loc> is to provide a simplified mechanism to declare
+processor profile requirements that must be met in order to process the document (in the absence of an end-user override).</p>
+</note>
+</div3>
+<div3 id="isd-vocabulary-isd">
+<head>isd:isd</head>
+<p>The <el>isd:isd</el> element serves either as (1) the root document element of a standalone <loc href="#terms-intermediate-synchronic-document">Intermediate
+Synchronic Document</loc> or (2) as a child of an <loc href="#isd-vocabulary-sequence"><el>isd:sequence</el></loc> element of a
+<loc href="#terms-intermediate-synchronic-document-sequence">Intermediate Synchronic Document Sequence</loc> document.</p>
+<p>The <el>isd:isd</el> element accepts as its children zero or more elements in the
+<loc href="#element-vocab-group-metadata"><code>Metadata.class</code></loc> element group,
+followed by zero or one <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc> element,
+followed by zero or more <loc href="#isd-vocabulary-css"><el>isd:css</el></loc> elements,
+followed by zero or more <loc href="#isd-vocabulary-region"><el>isd:region</el></loc> elements.</p>
+<table id="elt-syntax-isd" role="syntax">
+<caption>XML Representation &ndash; Element Information Item: isd:isd</caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+&lt;isd:isd
+  <loc href="#timing-attribute-begin"><phrase role="reqattr">begin</phrase></loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
+  <loc href="#timing-attribute-end"><phrase role="reqattr">end</phrase></loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
+  version = xsd:positiveInteger
+  <loc href="#content-attribute-lang">xml:lang</loc> = string
+  {<emph>any attribute in the <loc href="#isd-parameter-attribute-set">ISD Parameter Attribute Set</loc></emph>}&gt;
+  {<emph>any attribute not in default or any TT namespace</emph>}&gt;
+  <emph>Content:</emph> <loc href="#element-vocab-group-metadata">Metadata.class</loc>*, <loc href="#parameter-vocabulary-profile">ttp:profile</loc>?, <loc href="#isd-vocabulary-css">isd:css</loc>*, <loc href="#isd-vocabulary-region">isd:region</loc>*
+&lt;/isd:isd&gt;
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<p>A <att>begin</att> attribute must be specified, the value of which must take the <emph>offset-time</emph> form of
+a <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>, and, further, is restricted to use a metric of
+<code>s</code> (seconds),
+<code>f</code> (frames),
+<code>t</code> (ticks), or may omit the metric, in which case <code>s</code> seconds is implied. This
+begin time is expressed as an offset from the begin time of the <loc href="#terms-root-temporal-extent">root temporal extent</loc>
+of the source TTML document from which this <loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> element was derived.</p>
+<p>An <att>end</att> attribute must be similarlly specified, where the same constraints apply.
+This end time is expressed as an offset from the begin time of the <loc href="#terms-root-temporal-extent">root temporal extent</loc>
+of the source TTML document from which this <loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> element was derived.</p>
+<note role="elaboration">
+<p>Expressed in the terminology of <bibref ref="smil3"/>, the values of these <att>begin</att> and <att>end</att> attributes
+correspond to the resolved begin and end times of the <emph>active duration</emph> with respect to the <emph>document begin</emph>.</p>
+</note>
+<p>An <loc href="#content-attribute-lang"><att>xml:lang</att></loc> attribute must be specified on the
+<loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> element if it is a standalone <loc href="#terms-intermediate-synchronic-document">Intermediate
+Synchronic Document</loc> document; otherwise, it may be specified, and should be specified if the default language of the 
+<loc href="#isd-vocabulary-sequence"><el>isd:isd</el></loc> element differs from the default language of its
+parent <loc href="#isd-vocabulary-sequence"><el>isd:sequence</el></loc> element.
+If its value is empty, it signifies that there is no default language that applies
+to the content within the <loc href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</loc>. Otherwise,
+the specified value denotes the default language that applies.</p>
+<p>The <att>version</att> attribute follows the syntax and semantics of the same named attribute on the
+<loc href="#isd-vocabulary-sequence"><el>isd:sequence</el></loc> element type. The <att>version</att>
+attribute must not be specified on an <loc href="#isd-vocabulary-isd">isd:isd</loc> element that is not
+a root document element, i.e., is a child element of an <loc href="#isd-vocabulary-sequence">isd:sequence</loc> element.</p>
+<p>A child <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc> element may be present if the
+<loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> element is a standalone <loc href="#terms-intermediate-synchronic-document">Intermediate
+Synchronic Document</loc> document, in which case the same constraints and semantics apply as specified in <specref ref="isd-vocabulary-sequence"/>;
+otherwise, if not a standalone document, a child <loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc> element must not be present.</p>
+</div3>
+<div3 id="isd-vocabulary-css">
+<head>isd:css</head>
+<p>The <el>isd:css</el> element is used to represent a unique computed style set of some collection of elements
+that share the same set of computed styles. In particular, for each
+element <emph>E</emph> in the source TTML document which is selected and copied into a
+<loc href="#isd-vocabulary-region"><el>isd:region</el></loc> element of a given
+<loc href="#terms-intermediate-synchronic-document">Intermediate Synchronic Document</loc>, the computed style
+set of <emph>E</emph>, <emph>CSS(E)</emph>, is determined, and, if that <emph>CSS(E)</emph> is not already specified
+by an existing <el>isd:css</el> element, then it is assigned a unique identifier and instantiated as a new
+<el>isd:css</el> element.</p>
+<p>The <el>isd:css</el> element accepts as its children zero or more elements in the
+<loc href="#element-vocab-group-metadata"><code>Metadata.class</code></loc> element group.</p>
+<table id="elt-syntax-isd-style" role="syntax">
+<caption>XML Representation &ndash; Element Information Item: isd:css</caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+&lt;isd:css
+  <loc href="#content-attribute-id"><phrase role="reqattr">xml:id</phrase></loc> = ID
+  {<emph>any attribute in TT Style namespace</emph>}
+  {<emph>any attribute not in default or any TT namespace</emph>}&gt;
+  <emph>Content:</emph> <loc href="#element-vocab-group-metadata">Metadata.class</loc>*
+&lt;/isd:css&gt;
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<p>For each arbitrary pair of <el>isd:css</el> child elements of an
+<loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> element,
+<emph>S1</emph> and <emph>S2</emph>, the set of specified styles of <emph>S1</emph> must
+not be the same as the set of specified styles of <emph>S2</emph>. For the purpose of comparing two
+sets of specified styles, the styles must be placed into a canonical order and then compared item
+by item for value equality, where the canonical order is in accordance to the qualified attribute name
+order, where each qualified name consists of a tuple <code>&lt;namespace URL, local name&gt;</code>,
+and such tuples are compared component-wise by case-sensitive lexical string order.</p>
+</div3>
+<div3 id="isd-vocabulary-region">
+<head>isd:region</head>
+<p>The <el>isd:region</el> element is used to represent a layout and presentation region
+and the content selected into that region, where that content takes the form of a
+<loc href="#document-structure-vocabulary-body">body</loc> element and its descendant TTML content elements.</p>
+<p>The <el>isd:region</el> element accepts as its children zero or more elements in the
+<loc href="#element-vocab-group-metadata"><code>Metadata.class</code></loc> element group,
+followed by zero or more <loc href="#animation-vocabulary-animate"><el>animate</el></loc> elements,
+followed by exactly one <loc href="#document-structure-vocabulary-body"><el>body</el></loc> element.</p>
+<table id="elt-syntax-isd-region" role="syntax">
+<caption>XML Representation &ndash; Element Information Item: isd:region</caption>
+<tbody>
+<tr>
+<td>
+<eg xml:space="preserve">
+&lt;isd:region
+  <loc href="#style-attribute-style">style</loc> = IDREF
+  <loc href="#metadata-attribute-role">ttm:role</loc> = string
+  <loc href="#content-attribute-id"><phrase role="reqattr">xml:id</phrase></loc> = ID
+  {<emph>any attribute not in default or any TT namespace</emph>}&gt;
+  <emph>Content:</emph> <loc href="#element-vocab-group-metadata">Metadata.class</loc>*, <loc href="#animation-vocabulary-animate">animate</loc>*, <loc href="#document-structure-vocabulary-body">body</loc>
+&lt;/isd:region&gt;
+</eg>
+</td>
+</tr>
+</tbody>
+</table>
+<p>If the computed style set of the region represented by the <el>isd:region</el> element is not the
+set of initial style values that apply to <loc href="#layout-vocabulary-region"><el>region</el></loc>, then a
+<att>style</att> attribute must be specified which references an <loc href="#isd-vocabulary-css"><el>isd:css</el></loc> element that specifies the
+region's computed style set.</p>
+<p>The following constraints apply to the <loc href="#document-structure-vocabulary-body"><el>body</el></loc> element
+and its descendant elements:</p>
+<ulist>
+<item><p>no <att>animate</att> attribute is specified;</p></item>
+<item><p>no <att>begin</att> attribute is specified;</p></item>
+<item><p>no <att>dur</att> attribute is specified;</p></item>
+<item><p>no <att>end</att> attribute is specified;</p></item>
+<item><p>no <att>region</att> attribute is specified;</p></item>
+<item><p>no <att>timeContainer</att> attribute is specified;</p></item>
+<item><p>no attribute in the TT Style namespace is specified;</p></item>
+<item><p>no <loc href="#animation-vocabulary-set">set</loc> element is present;</p></item>
+<item><p>no significant text node, i.e., text node in a #PCDATA context, is not contained in a 
+<loc href="#content-vocabulary-span"><el>span</el></loc> element that contains no other child.</p></item>
+</ulist>
+<p>In addition, for the <loc href="#document-structure-vocabulary-body"><el>body</el></loc> element <emph>B</emph> and
+each of its descendant content elements <emph>C</emph>, if the computed style set of <emph>B</emph> or each <emph>C</emph> is
+not equal to the computed style set of its parent element, then that element, <emph>B</emph> or <emph>C</emph>, must specify a <att>style</att>
+attribute that references an <loc href="#isd-vocabulary-css"><el>isd:css</el></loc> element that specifies the
+element's computed style set.</p>
+</div3>
+</div2>
+<div2 id="isd-parameter-attribute-set">
+<head>ISD Parameter Attribute Set</head>
+<p>The following subset of the defined <loc href="#attribute-vocab-group-parameters">Parameter Attributes</loc>
+are available for use with an
+<loc href="#isd-vocabulary-structure"><el>isd:structure</el></loc> or
+<loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> element as described above:</p>
+<ulist>
+<item><p><loc href="#parameter-attribute-cellResolution">ttp:cellResolution</loc></p></item>
+<item><p><loc href="#parameter-attribute-frameRate">ttp:frameRate</loc></p></item>
+<item><p><loc href="#parameter-attribute-frameRateMultiplier">ttp:frameRateMultipler</loc></p></item>
+<item><p><loc href="#parameter-attribute-mediaOffset">ttp:mediaOffset</loc></p></item>
+<item><p><loc href="#parameter-attribute-pixelAspectRatio">ttp:pixelAspectRatio</loc></p></item>
+<item><p><loc href="#parameter-attribute-subFrameRate">ttp:subFrameRate</loc></p></item>
+<item><p><loc href="#parameter-attribute-tickRate">ttp:tickRate</loc></p></item>
+</ulist>
+</div2>
+<div2 id="isd-interchange">
+<head>ISD Interchange</head>
+<p>A concrete document instance that employs the <loc href="#isd">Intermediate Synchronic Document Syntax</loc> must be
+encoded as a well-formed <bibref ref="xml10"/> document using the UTF-8 character encoding. Furthermore, such a document must specify
+an <loc href="#isd-vocabulary-sequence"><el>isd:sequence</el></loc> element or
+an <loc href="#isd-vocabulary-isd"><el>isd:isd</el></loc> element as the root document element.</p>
+<p>When a resource consisting of a concrete ISD Sequence or ISD instance is interchanged and a media type is used to identify the content type
+of that resource, then the media type <code>application/ttml+xml</code> should be used, about which see <bibref ref="ttml1"/> Appendix C.
+If this media type is used, the optional <code>profile</code> parameter must not be specified, or, if specified, must be ignored by a processor.</p>
+</div2>
+<div2 id="isd-examples">
+<head>ISD Examples</head>
+<p><emph>This sub-section is non-normative.</emph></p>
+<ednote>
+<name>Add ISD Examples</name>
+<date>2014-09-22</date>
+<edtext>Add worked out examples of ISD Sequence and ISD document instances.</edtext>
+</ednote>
+</div2>
+</div1>
 <div1 id="features">
 <head>Features</head>
 <p><emph>This appendix is normative.</emph></p>
@@ -11428,13 +12151,10 @@
 <eg xml:space="preserve">
 feature-designation
   : feature-namespace designation
-
 feature-namespace
   : <emph>TT Feature Namespace</emph>                    // http://www.w3.org/ns/ttml/feature/
-
 designation
   : "#" token-char+
-
 token-char
   : { XML NameChar }                        // XML 1.1 Production [4a]
 </eg>
@@ -13839,7 +14559,6 @@
 <loc href="#document-structure-vocabulary-head"><el>head</el></loc>
 </td>
 </tr>
-
 <tr>
 <td><loc href="#feature-time-offset"><code>#time-offset</code></loc></td>
 <td></td>
@@ -13937,14 +14656,11 @@
 <eg xml:space="preserve">
 extension-designation
   : extension-namespace designation
-
 extension-namespace
   : <emph>TT Extension Namespace</emph>                  // http://www.w3.org/ns/ttml/extension/
   | <emph>Other Extension Namespace</emph>               // expressed as an absolute URI
-
 designation
   : "#" token-char+
-
 token-char
   : { XML NameChar }                        // XML 1.1 Production [4a]
 </eg>
@@ -14010,7 +14726,6 @@
 <eg xml:space="preserve">&profile-ttml2-full;</eg>
 </div2>
 </div1>
-
 <div1 id="references">
 <head>References</head>
 <p><emph>This appendix is normative.</emph></p>
@@ -14026,6 +14741,11 @@
 Module Level 3</titleref>, W3C Recommendation, 07 June 2011. (See
 <xspecref href="http://www.w3.org/TR/2011/REC-css3-color-20110607/">http://www.w3.org/TR/2011/REC-css3-color-20110607/</xspecref>.)
 </bibl>
+<bibl id="cssruby" key="CSS Ruby">Elika Etemad and Koji Ishii,
+<titleref href="http://dev.w3.org/csswg/css-ruby-1/">CSS Ruby Layout Module Level 1</titleref>
+W3C Editor's Draft.
+(See <xspecref href="http://dev.w3.org/csswg/css-ruby-1/">http://dev.w3.org/csswg/css-ruby-1//</xspecref>.)
+</bibl>
 <bibl id="gps" key="GPS">
 <titleref href="http://tycho.usno.navy.mil/gpsinfo.html">Global
 Positioning System</titleref>, US Naval Observatory.
@@ -14044,6 +14764,11 @@
 Schema Definition Language (DSDL) &ndash; Part 2: Regular-grammar-based validation &ndash; RELAX NG</titleref>,
 International Organization for Standardization (ISO).
 </bibl>
+<bibl id="ruby" key="Ruby">Masayasu Ishikawa et al.,
+<titleref href="http://www.w3.org/TR/2001/REC-ruby-20010531/">Ruby Annotation</titleref>
+W3C Recommendation, 31 May 2001.
+(See <xspecref href="http://www.w3.org/TR/2001/REC-ruby-20010531/">http://www.w3.org/TR/2001/REC-ruby-20010531/</xspecref>.)
+</bibl>
 <bibl id="smil3" key="SMIL 3.0">Dick Bultermann, et al.,
 <titleref href="http://www.w3.org/TR/2008/REC-SMIL3-20081201/">Synchronized
 Multimedia Integration Language (SMIL 3.0)</titleref>,
@@ -14182,6 +14907,11 @@
 <titleref href="http://dublincore.org/documents/dces/">Dublin Core Metadata Element Set, Version 1.1: Reference Description</titleref>. (See
 <xspecref href="http://dublincore.org/documents/dces/">http://dublincore.org/documents/dces/</xspecref>.)
 </bibl>
+<bibl id="jlreq" key="JLREQ">Richard Ishida et al.,
+<titleref href="http://www.w3.org/TR/2012/NOTE-jlreq-20120403/">Requirements for Japanese Text Layout</titleref>
+W3C Working Group Note, 3 April 2012.
+(See <xspecref href="http://www.w3.org/TR/2012/NOTE-jlreq-20120403/">http://www.w3.org/TR/2012/NOTE-jlreq-20120403/</xspecref>.)
+</bibl>
 <bibl id="mpeg7-5" key="MPEG7-5">
 ISO/IEC 15938-5,
 <titleref
@@ -14189,6 +14919,11 @@
 interface &ndash; Part 5: Multimedia description schemes</titleref>,
 International Organization for Standardization (ISO).
 </bibl>
+<bibl id="nsoriginal" key="NSOriginal">Tim Bray, et al.
+<titleref href="http://www.w3.org/TR/1999/REC-xml-names-19990114/">Namespaces
+in XML</titleref>, W3C Recommendation, 14 January 1999. (See
+<xspecref href="http://www.w3.org/TR/1999/REC-xml-names-19990114/">http://www.w3.org/TR/1999/REC-xml-names-19990114/</xspecref>.)
+</bibl>
 <bibl id="nsstate" key="NSState">Norman Walsh, Ed.,
 <titleref
 href="http://www.w3.org/2001/tag/doc/namespaceState-2006-01-09.html">The Disposition
@@ -14885,7 +15620,6 @@
 <td>[email protected], [email protected], [email protected]:base</td>
 <td>2,5,9</td>
 </tr>
-
 <tr>
 <td><loc href="#parameter-vocabulary-extension"><code>ttp:extension</code></loc></td>
 <td><code>@requiredExtensions</code></td>
@@ -16136,8 +16870,9 @@
 <p>If the computed <code>frameRateMultipler</code> ratio is not integral, then <code>effectiveFrameRate</code> will be a non-integral rational.</p>
 </note>
 <note role="clarification">
-<p>The above formalisms assumes that the <loc href="#terms-root-temporal-extent">root temporal extent</loc> corresponds with the beginning of a related media object. If
-this assumption doesn't hold, then an additional offset that accounts for the difference may be introduced when computing media time <code>M</code>.</p>
+<p>The begin time of the <loc href="#terms-root-temporal-extent">root temporal extent</loc> is related to the begin time of a
+<loc href="#terms-related-media-object">related media object</loc> in accordance with the computed value of the
+<loc href="#parameter-attribute-mediaOffset"><att>ttp:mediaOffset</att></loc> parameter property.</p>
 </note>
 </div2>
 <div2 id="time-expression-semantics-smpte">
@@ -16252,6 +16987,11 @@
 <p>Given the derived media time base as described above, then 
 media time base <phrase role="strong"><code>M</code></phrase> is related to the local real time <phrase role="strong"><code>R</code></phrase>
 as described in <specref ref="time-expression-semantics-media"/> above.</p>
+<note role="clarification">
+<p>The begin time of the <loc href="#terms-root-temporal-extent">root temporal extent</loc> is related to the begin time of a
+<loc href="#terms-related-media-object">related media object</loc> in accordance with the computed value of the
+<loc href="#parameter-attribute-mediaOffset"><att>ttp:mediaOffset</att></loc> parameter property.</p>
+</note>
 </div2>
 </div1>
 <inform-div1 id="common-styling">
Binary file ttml2/spec/xsd/schema.zip has changed
--- a/ttml2/spec/xsd/ttml2-datatypes.xsd	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/xsd/ttml2-datatypes.xsd	Tue Sep 23 15:34:45 2014 -0700
@@ -247,6 +247,27 @@
       <xs:enumeration value="discontinuous"/>
     </xs:restriction>
   </xs:simpleType>
+  <xs:simpleType name="mediaDuration">
+    <xs:annotation>
+      <xs:documentation>timeExpression (offset-time form only) | indefinite</xs:documentation>
+    </xs:annotation>
+    <xs:union>
+      <xs:simpleType>
+        <xs:restriction base="ttd:timeDuration"/>
+      </xs:simpleType>
+      <xs:simpleType>
+        <xs:restriction base="xs:token">
+          <xs:enumeration value="indefinite"/>
+        </xs:restriction>
+      </xs:simpleType>
+    </xs:union>
+  </xs:simpleType>
+  <xs:simpleType name="mediaOffset">
+    <xs:annotation>
+      <xs:documentation>sign? timeExpression (offset-time form only)</xs:documentation>
+    </xs:annotation>
+    <xs:restriction base="xs:string"/>
+  </xs:simpleType>
   <xs:simpleType name="metadataAgentType">
     <xs:restriction base="xs:token">
       <xs:enumeration value="person"/>
@@ -385,6 +406,32 @@
       </xs:simpleType>
     </xs:union>
   </xs:simpleType>
+  <xs:simpleType name="ruby">
+    <xs:restriction base="xs:token">
+      <xs:enumeration value="none"/>
+      <xs:enumeration value="container"/>
+      <xs:enumeration value="base"/>
+      <xs:enumeration value="baseContainer"/>
+      <xs:enumeration value="text"/>
+      <xs:enumeration value="textContainer"/>
+      <xs:enumeration value="delimiter"/>
+    </xs:restriction>
+  </xs:simpleType>
+  <xs:simpleType name="rubyAlign">
+    <xs:restriction base="xs:token">
+      <xs:enumeration value="start"/>
+      <xs:enumeration value="center"/>
+      <xs:enumeration value="spaceBetween"/>
+      <xs:enumeration value="spaceAround"/>
+    </xs:restriction>
+  </xs:simpleType>
+  <xs:simpleType name="rubyPosition">
+    <xs:restriction base="xs:token">
+      <xs:enumeration value="before"/>
+      <xs:enumeration value="after"/>
+      <xs:enumeration value="interCharacter"/>
+    </xs:restriction>
+  </xs:simpleType>
   <xs:simpleType name="showBackground">
     <xs:restriction base="xs:token">
       <xs:enumeration value="always"/>
--- a/ttml2/spec/xsd/ttml2-document.xsd	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/xsd/ttml2-document.xsd	Tue Sep 23 15:34:45 2014 -0700
@@ -18,7 +18,7 @@
   <xs:attributeGroup name="tt.attlist">
     <xs:attributeGroup ref="tt:Core.required.attrib.class"/>
     <xs:attributeGroup ref="ttp:Parameter.attrib.class"/>
-    <xs:attribute ref="tts:extent"/>
+    <xs:attributeGroup ref="tt:Styled.attrib.class"/>
   </xs:attributeGroup>
   <xs:complexType name="tt.eltype">
     <xs:sequence>
--- a/ttml2/spec/xsd/ttml2-parameter-attribs.xsd	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/xsd/ttml2-parameter-attribs.xsd	Tue Sep 23 15:34:45 2014 -0700
@@ -15,6 +15,8 @@
   <xs:attribute name="inferProcessorProfileMethod" type="ttd:inferProcessorProfileMethod"/>
   <xs:attribute name="inferProcessorProfileSource" type="ttd:inferProcessorProfileSource"/>
   <xs:attribute name="markerMode" type="ttd:markerMode"/>
+  <xs:attribute name="mediaDuration" type="ttd:mediaDuration"/>
+  <xs:attribute name="mediaOffset" type="ttd:mediaOffset"/>
   <xs:attribute name="processorProfiles" type="ttd:profiles"/>
   <xs:attribute name="processorProfileCombination" type="ttd:profileCombination"/>
   <xs:attribute name="permitFeatureNarrowing" type="ttd:permitFeatureNarrowingOrWidening"/>
@@ -38,6 +40,8 @@
     <xs:attribute ref="ttp:inferProcessorProfileMethod"/>
     <xs:attribute ref="ttp:inferProcessorProfileSource"/>
     <xs:attribute ref="ttp:markerMode"/>
+    <xs:attribute ref="ttp:mediaDuration"/>
+    <xs:attribute ref="ttp:mediaOffset"/>
     <xs:attribute ref="ttp:permitFeatureNarrowing"/>
     <xs:attribute ref="ttp:permitFeatureWidening"/>
     <xs:attribute ref="ttp:processorProfiles"/>
--- a/ttml2/spec/xsd/ttml2-styling-attribs.xsd	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/xsd/ttml2-styling-attribs.xsd	Tue Sep 23 15:34:45 2014 -0700
@@ -21,6 +21,9 @@
   <xs:attribute name="origin" type="ttd:origin"/>
   <xs:attribute name="overflow" type="ttd:overflow"/>
   <xs:attribute name="padding" type="ttd:padding"/>
+  <xs:attribute name="ruby" type="ttd:ruby"/>
+  <xs:attribute name="rubyAlign" type="ttd:rubyAlign"/>
+  <xs:attribute name="rubyPosition" type="ttd:rubyPosition"/>
   <xs:attribute name="showBackground" type="ttd:showBackground"/>
   <xs:attribute name="textAlign" type="ttd:textAlign"/>
   <xs:attribute name="textDecoration" type="ttd:textDecoration"/>
@@ -49,6 +52,9 @@
     <xs:attribute ref="tts:overflow"/>
     <xs:attribute ref="tts:padding"/>
     <xs:attribute ref="tts:showBackground"/>
+    <xs:attribute ref="tts:ruby"/>
+    <xs:attribute ref="tts:rubyAlign"/>
+    <xs:attribute ref="tts:rubyPosition"/>
     <xs:attribute ref="tts:textAlign"/>
     <xs:attribute ref="tts:textDecoration"/>
     <xs:attribute ref="tts:textOrientation"/>
--- a/ttml2/spec/xsd/ttml2-styling.xsd	Tue Sep 23 15:33:38 2014 -0700
+++ b/ttml2/spec/xsd/ttml2-styling.xsd	Tue Sep 23 15:34:45 2014 -0700
@@ -21,9 +21,14 @@
     <xs:attributeGroup ref="tt:Core.attrib.class"/>
     <xs:attributeGroup ref="tt:Styled.attrib.class"/>
   </xs:attributeGroup>
+  <xs:attributeGroup name="initial.attlist">
+    <xs:attributeGroup ref="tt:Core.attrib.class"/>
+    <xs:attributeGroup ref="tt:Styled.attrib.class"/>
+  </xs:attributeGroup>
   <xs:complexType name="styling.eltype">
     <xs:sequence>
       <xs:group ref="tt:Metadata.class" minOccurs="0" maxOccurs="unbounded"/>
+      <xs:element ref="tt:initial" minOccurs="0" maxOccurs="unbounded"/>
       <xs:element ref="tt:style" minOccurs="0" maxOccurs="unbounded"/>
     </xs:sequence>
     <xs:attributeGroup ref="tt:styling.attlist"/>
@@ -34,6 +39,13 @@
     </xs:sequence>
     <xs:attributeGroup ref="tt:style.attlist"/>
   </xs:complexType>
+  <xs:complexType name="initial.eltype">
+    <xs:sequence>
+      <xs:group ref="tt:Metadata.class" minOccurs="0" maxOccurs="unbounded"/>
+    </xs:sequence>
+    <xs:attributeGroup ref="tt:initial.attlist"/>
+  </xs:complexType>
   <xs:element name="styling" type="tt:styling.eltype"/>
   <xs:element name="style" type="tt:style.eltype"/>
+  <xs:element name="initial" type="tt:initial.eltype"/>
 </xs:schema>