New sets of changes from Sean
authorPhilippe Le Hégaret <plh@w3.org>
Mon, 31 May 2010 11:23:45 +0000
changeset 203 96eb5fd70a1f
parent 202 7f976b06d574
child 204 dd40f85f8213
New sets of changes from Sean
spec/profiles/dfxp-full.xml
spec/profiles/dfxp-presentation.xml
spec/profiles/dfxp-transformation.xml
spec/rnc/ttaf1-dfxp-datatypes.rnc
spec/rnc/ttaf1-dfxp-styling-attribs.rnc
spec/rnc/ttaf1-dfxp-styling.rnc
spec/ttaf1-dfxp.html
spec/ttaf1-dfxp.xml
spec/xsd/ttaf1-dfxp-datatypes.xsd
spec/xsd/ttaf1-dfxp-styling-attribs.xsd
spec/xsd/ttaf1-dfxp-styling.xsd
--- a/spec/profiles/dfxp-full.xml	Thu May 13 16:55:59 2010 +0000
+++ b/spec/profiles/dfxp-full.xml	Mon May 31 11:23:45 2010 +0000
@@ -1,142 +1,129 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- this file defines the "dfxp-full" profile of ttaf1-dfxp -->
-<profile xmlns="http://www.w3.org/ns/ttml#parameter">
-<features xml:base="http://www.w3.org/ns/ttml/feature/">
-<!-- required (mandatory) feature support -->
-<feature value="required">#animation</feature>
-<feature value="required">#backgroundColor-block</feature>
-<feature value="required">#backgroundColor-inline</feature>
-<feature value="required">#backgroundColor-region</feature>
-<feature value="required">#backgroundColor</feature>
-<feature value="required">#bidi</feature>
-<feature value="required">#cellResolution</feature>
-<feature value="required">#clockMode-gps</feature>
-<feature value="required">#clockMode-local</feature>
-<feature value="required">#clockMode-utc</feature>
-<feature value="required">#clockMode</feature>
-<feature value="required">#color</feature>
-<feature value="required">#content</feature>
-<feature value="required">#core</feature>
-<feature value="required">#direction</feature>
-<feature value="required">#display-block</feature>
-<feature value="required">#display-inline</feature>
-<feature value="required">#display-region</feature>
-<feature value="required">#display</feature>
-<feature value="required">#displayAlign</feature>
-<feature value="required">#dropMode-dropNTSC</feature>
-<feature value="required">#dropMode-dropPAL</feature>
-<feature value="required">#dropMode-nonDrop</feature>
-<feature value="required">#dropMode</feature>
-<feature value="required">#dynamicFlow-character</feature>
-<feature value="required">#dynamicFlow-clear</feature>
-<feature value="required">#dynamicFlow-fill</feature>
-<feature value="required">#dynamicFlow-glyph</feature>
-<feature value="required">#dynamicFlow-in</feature>
-<feature value="required">#dynamicFlow-jump</feature>
-<feature value="required">#dynamicFlow-line</feature>
-<feature value="required">#dynamicFlow-out</feature>
-<feature value="required">#dynamicFlow-rollUp</feature>
-<feature value="required">#dynamicFlow-smooth</feature>
-<feature value="required">#dynamicFlow-teletext</feature>
-<feature value="required">#dynamicFlow-word</feature>
-<feature value="required">#dynamicFlow</feature>
-<feature value="required">#extent-region</feature>
-<feature value="required">#extent-root</feature>
-<feature value="required">#extent</feature>
-<feature value="required">#fontFamily-generic</feature>
-<feature value="required">#fontFamily-non-generic</feature>
-<feature value="required">#fontFamily</feature>
-<feature value="required">#fontSize-anamorphic</feature>
-<feature value="required">#fontSize-isomorphic</feature>
-<feature value="required">#fontSize</feature>
-<feature value="required">#fontStyle-italic</feature>
-<feature value="required">#fontStyle-oblique</feature>
-<feature value="required">#fontStyle-reverseOblique</feature>
-<feature value="required">#fontStyle</feature>
-<feature value="required">#fontWeight-bold</feature>
-<feature value="required">#fontWeight</feature>
-<feature value="required">#frameRate</feature>
-<feature value="required">#frameRateMultiplier</feature>
-<feature value="required">#layout</feature>
-<feature value="required">#length-cell</feature>
-<feature value="required">#length-em</feature>
-<feature value="required">#length-negative</feature>
-<feature value="required">#length-percentage</feature>
-<feature value="required">#length-pixel</feature>
-<feature value="required">#length-positive</feature>
-<feature value="required">#length-real</feature>
-<feature value="required">#length</feature>
-<feature value="required">#lineBreak-uax14</feature>
-<feature value="required">#lineHeight</feature>
-<feature value="required">#markerMode-continuous</feature>
-<feature value="required">#markerMode-discontinuous</feature>
-<feature value="required">#markerMode</feature>
-<feature value="required">#metadata-foreign</feature>
-<feature value="required">#metadata</feature>
-<feature value="required">#nested-div</feature>
-<feature value="required">#nested-span</feature>
-<feature value="required">#opacity</feature>
-<feature value="required">#origin</feature>
-<feature value="required">#overflow-scroll</feature>
-<feature value="required">#overflow-visible</feature>
-<feature value="required">#overflow</feature>
-<feature value="required">#padding-1</feature>
-<feature value="required">#padding-2</feature>
-<feature value="required">#padding-3</feature>
-<feature value="required">#padding-4</feature>
-<feature value="required">#padding</feature>
-<feature value="required">#pixelAspectRatio</feature>
-<feature value="required">#presentation</feature>
-<feature value="required">#profile</feature>
-<feature value="required">#rollUp</feature>
-<feature value="required">#showBackground</feature>
-<feature value="required">#structure</feature>
-<feature value="required">#styling-chained</feature>
-<feature value="required">#styling-inheritance-content</feature>
-<feature value="required">#styling-inheritance-region</feature>
-<feature value="required">#styling-inline</feature>
-<feature value="required">#styling-nested</feature>
-<feature value="required">#styling-referential</feature>
-<feature value="required">#styling</feature>
-<feature value="required">#subFrameRate</feature>
-<feature value="required">#textAlign-absolute</feature>
-<feature value="required">#textAlign-relative</feature>
-<feature value="required">#textAlign</feature>
-<feature value="required">#textDecoration-over</feature>
-<feature value="required">#textDecoration-through</feature>
-<feature value="required">#textDecoration-under</feature>
-<feature value="required">#textDecoration</feature>
-<feature value="required">#textOutline-blurred</feature>
-<feature value="required">#textOutline-unblurred</feature>
-<feature value="required">#textOutline</feature>
-<feature value="required">#tickRate</feature>
-<feature value="required">#time-clock-with-frames</feature>
-<feature value="required">#time-clock</feature>
-<feature value="required">#time-offset-with-frames</feature>
-<feature value="required">#time-offset-with-ticks</feature>
-<feature value="required">#time-offset</feature>
-<feature value="required">#timeBase-clock</feature>
-<feature value="required">#timeBase-media</feature>
-<feature value="required">#timeBase-smpte</feature>
-<feature value="required">#timeContainer</feature>
-<feature value="required">#timing</feature>
-<feature value="required">#transformation</feature>
-<feature value="required">#unicodeBidi</feature>
-<feature value="required">#visibility-block</feature>
-<feature value="required">#visibility-inline</feature>
-<feature value="required">#visibility-region</feature>
-<feature value="required">#visibility</feature>
-<feature value="required">#wrapOption</feature>
-<feature value="required">#writingMode-horizontal-lr</feature>
-<feature value="required">#writingMode-horizontal-rl</feature>
-<feature value="required">#writingMode-horizontal</feature>
-<feature value="required">#writingMode-vertical</feature>
-<feature value="required">#writingMode</feature>
-<feature value="required">#zIndex</feature>
-<!-- optional (voluntary) feature support -->
-</features>
-<extensions xml:base="http://www.w3.org/ns/ttml/extension/">
-<!-- required (mandatory) extension support -->
-<!-- optional (voluntary) extension support -->
-</extensions>
-</profile>
+<?xml version="1.0" encoding="utf-8"?>
+<!-- this file defines the "dfxp-full" profile of ttaf1-dfxp -->
+<profile xmlns="http://www.w3.org/ns/ttml#parameter">
+  <features xml:base="http://www.w3.org/ns/ttml/feature/">
+    <!-- required (mandatory) feature support -->
+    <feature value="required">#animation</feature>
+    <feature value="required">#backgroundColor-block</feature>
+    <feature value="required">#backgroundColor-inline</feature>
+    <feature value="required">#backgroundColor-region</feature>
+    <feature value="required">#backgroundColor</feature>
+    <feature value="required">#bidi</feature>
+    <feature value="required">#cellResolution</feature>
+    <feature value="required">#clockMode-gps</feature>
+    <feature value="required">#clockMode-local</feature>
+    <feature value="required">#clockMode-utc</feature>
+    <feature value="required">#clockMode</feature>
+    <feature value="required">#color</feature>
+    <feature value="required">#content</feature>
+    <feature value="required">#core</feature>
+    <feature value="required">#direction</feature>
+    <feature value="required">#display-block</feature>
+    <feature value="required">#display-inline</feature>
+    <feature value="required">#display-region</feature>
+    <feature value="required">#display</feature>
+    <feature value="required">#displayAlign</feature>
+    <feature value="required">#dropMode-dropNTSC</feature>
+    <feature value="required">#dropMode-dropPAL</feature>
+    <feature value="required">#dropMode-nonDrop</feature>
+    <feature value="required">#dropMode</feature>
+    <feature value="required">#extent-region</feature>
+    <feature value="required">#extent-root</feature>
+    <feature value="required">#extent</feature>
+    <feature value="required">#fontFamily-generic</feature>
+    <feature value="required">#fontFamily-non-generic</feature>
+    <feature value="required">#fontFamily</feature>
+    <feature value="required">#fontSize-anamorphic</feature>
+    <feature value="required">#fontSize-isomorphic</feature>
+    <feature value="required">#fontSize</feature>
+    <feature value="required">#fontStyle-italic</feature>
+    <feature value="required">#fontStyle-oblique</feature>
+    <feature value="required">#fontStyle-reverseOblique</feature>
+    <feature value="required">#fontStyle</feature>
+    <feature value="required">#fontWeight-bold</feature>
+    <feature value="required">#fontWeight</feature>
+    <feature value="required">#frameRate</feature>
+    <feature value="required">#frameRateMultiplier</feature>
+    <feature value="required">#layout</feature>
+    <feature value="required">#length-cell</feature>
+    <feature value="required">#length-em</feature>
+    <feature value="required">#length-negative</feature>
+    <feature value="required">#length-percentage</feature>
+    <feature value="required">#length-pixel</feature>
+    <feature value="required">#length-positive</feature>
+    <feature value="required">#length-real</feature>
+    <feature value="required">#length</feature>
+    <feature value="required">#lineBreak-uax14</feature>
+    <feature value="required">#lineHeight</feature>
+    <feature value="required">#markerMode-continuous</feature>
+    <feature value="required">#markerMode-discontinuous</feature>
+    <feature value="required">#markerMode</feature>
+    <feature value="required">#metadata-foreign</feature>
+    <feature value="required">#metadata</feature>
+    <feature value="required">#nested-div</feature>
+    <feature value="required">#nested-span</feature>
+    <feature value="required">#opacity</feature>
+    <feature value="required">#origin</feature>
+    <feature value="required">#overflow-scroll</feature>
+    <feature value="required">#overflow-visible</feature>
+    <feature value="required">#overflow</feature>
+    <feature value="required">#padding-1</feature>
+    <feature value="required">#padding-2</feature>
+    <feature value="required">#padding-3</feature>
+    <feature value="required">#padding-4</feature>
+    <feature value="required">#padding</feature>
+    <feature value="required">#pixelAspectRatio</feature>
+    <feature value="required">#presentation</feature>
+    <feature value="required">#profile</feature>
+    <feature value="required">#showBackground</feature>
+    <feature value="required">#structure</feature>
+    <feature value="required">#styling-chained</feature>
+    <feature value="required">#styling-inheritance-content</feature>
+    <feature value="required">#styling-inheritance-region</feature>
+    <feature value="required">#styling-inline</feature>
+    <feature value="required">#styling-nested</feature>
+    <feature value="required">#styling-referential</feature>
+    <feature value="required">#styling</feature>
+    <feature value="required">#subFrameRate</feature>
+    <feature value="required">#textAlign-absolute</feature>
+    <feature value="required">#textAlign-relative</feature>
+    <feature value="required">#textAlign</feature>
+    <feature value="required">#textDecoration-over</feature>
+    <feature value="required">#textDecoration-through</feature>
+    <feature value="required">#textDecoration-under</feature>
+    <feature value="required">#textDecoration</feature>
+    <feature value="required">#textOutline-blurred</feature>
+    <feature value="required">#textOutline-unblurred</feature>
+    <feature value="required">#textOutline</feature>
+    <feature value="required">#tickRate</feature>
+    <feature value="required">#time-clock-with-frames</feature>
+    <feature value="required">#time-clock</feature>
+    <feature value="required">#time-offset-with-frames</feature>
+    <feature value="required">#time-offset-with-ticks</feature>
+    <feature value="required">#time-offset</feature>
+    <feature value="required">#timeBase-clock</feature>
+    <feature value="required">#timeBase-media</feature>
+    <feature value="required">#timeBase-smpte</feature>
+    <feature value="required">#timeContainer</feature>
+    <feature value="required">#timing</feature>
+    <feature value="required">#transformation</feature>
+    <feature value="required">#unicodeBidi</feature>
+    <feature value="required">#visibility-block</feature>
+    <feature value="required">#visibility-inline</feature>
+    <feature value="required">#visibility-region</feature>
+    <feature value="required">#visibility</feature>
+    <feature value="required">#wrapOption</feature>
+    <feature value="required">#writingMode-horizontal-lr</feature>
+    <feature value="required">#writingMode-horizontal-rl</feature>
+    <feature value="required">#writingMode-horizontal</feature>
+    <feature value="required">#writingMode-vertical</feature>
+    <feature value="required">#writingMode</feature>
+    <feature value="required">#zIndex</feature>
+    <!-- optional (voluntary) feature support -->
+  </features>
+  <extensions xml:base="http://www.w3.org/ns/ttml/extension/">
+    <!-- required (mandatory) extension support -->
+    <!-- optional (voluntary) extension support -->
+  </extensions>
+</profile>
+
--- a/spec/profiles/dfxp-presentation.xml	Thu May 13 16:55:59 2010 +0000
+++ b/spec/profiles/dfxp-presentation.xml	Mon May 31 11:23:45 2010 +0000
@@ -1,142 +1,129 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- this file defines the "dfxp-presentation" profile of ttaf1-dfxp -->
-<profile xmlns="http://www.w3.org/ns/ttml#parameter">
-<features xml:base="http://www.w3.org/ns/ttml/feature/">
-<!-- required (mandatory) feature support -->
-<feature value="required">#content</feature>
-<feature value="required">#core</feature>
-<feature value="required">#presentation</feature>
-<feature value="required">#profile</feature>
-<feature value="required">#structure</feature>
-<feature value="required">#time-offset</feature>
-<feature value="required">#timing</feature>
-<!-- optional (voluntary) feature support -->
-<feature value="optional">#animation</feature>
-<feature value="optional">#backgroundColor-block</feature>
-<feature value="optional">#backgroundColor-inline</feature>
-<feature value="optional">#backgroundColor-region</feature>
-<feature value="optional">#backgroundColor</feature>
-<feature value="optional">#bidi</feature>
-<feature value="optional">#cellResolution</feature>
-<feature value="optional">#clockMode-gps</feature>
-<feature value="optional">#clockMode-local</feature>
-<feature value="optional">#clockMode-utc</feature>
-<feature value="optional">#clockMode</feature>
-<feature value="optional">#color</feature>
-<feature value="optional">#direction</feature>
-<feature value="optional">#display-block</feature>
-<feature value="optional">#display-inline</feature>
-<feature value="optional">#display-region</feature>
-<feature value="optional">#display</feature>
-<feature value="optional">#displayAlign</feature>
-<feature value="optional">#dropMode-dropNTSC</feature>
-<feature value="optional">#dropMode-dropPAL</feature>
-<feature value="optional">#dropMode-nonDrop</feature>
-<feature value="optional">#dropMode</feature>
-<feature value="optional">#dynamicFlow-character</feature>
-<feature value="optional">#dynamicFlow-clear</feature>
-<feature value="optional">#dynamicFlow-fill</feature>
-<feature value="optional">#dynamicFlow-glyph</feature>
-<feature value="optional">#dynamicFlow-in</feature>
-<feature value="optional">#dynamicFlow-jump</feature>
-<feature value="optional">#dynamicFlow-line</feature>
-<feature value="optional">#dynamicFlow-out</feature>
-<feature value="optional">#dynamicFlow-rollUp</feature>
-<feature value="optional">#dynamicFlow-smooth</feature>
-<feature value="optional">#dynamicFlow-teletext</feature>
-<feature value="optional">#dynamicFlow-word</feature>
-<feature value="optional">#dynamicFlow</feature>
-<feature value="optional">#extent-region</feature>
-<feature value="optional">#extent-root</feature>
-<feature value="optional">#extent</feature>
-<feature value="optional">#fontFamily-generic</feature>
-<feature value="optional">#fontFamily-non-generic</feature>
-<feature value="optional">#fontFamily</feature>
-<feature value="optional">#fontSize-anamorphic</feature>
-<feature value="optional">#fontSize-isomorphic</feature>
-<feature value="optional">#fontSize</feature>
-<feature value="optional">#fontStyle-italic</feature>
-<feature value="optional">#fontStyle-oblique</feature>
-<feature value="optional">#fontStyle-reverseOblique</feature>
-<feature value="optional">#fontStyle</feature>
-<feature value="optional">#fontWeight-bold</feature>
-<feature value="optional">#fontWeight</feature>
-<feature value="optional">#frameRate</feature>
-<feature value="optional">#frameRateMultiplier</feature>
-<feature value="optional">#layout</feature>
-<feature value="optional">#length-cell</feature>
-<feature value="optional">#length-em</feature>
-<feature value="optional">#length-negative</feature>
-<feature value="optional">#length-percentage</feature>
-<feature value="optional">#length-pixel</feature>
-<feature value="optional">#length-positive</feature>
-<feature value="optional">#length-real</feature>
-<feature value="optional">#length</feature>
-<feature value="optional">#lineBreak-uax14</feature>
-<feature value="optional">#lineHeight</feature>
-<feature value="optional">#markerMode-continuous</feature>
-<feature value="optional">#markerMode-discontinuous</feature>
-<feature value="optional">#markerMode</feature>
-<feature value="optional">#metadata-foreign</feature>
-<feature value="optional">#metadata</feature>
-<feature value="optional">#nested-div</feature>
-<feature value="optional">#nested-span</feature>
-<feature value="optional">#opacity</feature>
-<feature value="optional">#origin</feature>
-<feature value="optional">#overflow-scroll</feature>
-<feature value="optional">#overflow-visible</feature>
-<feature value="optional">#overflow</feature>
-<feature value="optional">#padding-1</feature>
-<feature value="optional">#padding-2</feature>
-<feature value="optional">#padding-3</feature>
-<feature value="optional">#padding-4</feature>
-<feature value="optional">#padding</feature>
-<feature value="optional">#pixelAspectRatio</feature>
-<feature value="optional">#rollUp</feature>
-<feature value="optional">#showBackground</feature>
-<feature value="optional">#styling-chained</feature>
-<feature value="optional">#styling-inheritance-content</feature>
-<feature value="optional">#styling-inheritance-region</feature>
-<feature value="optional">#styling-inline</feature>
-<feature value="optional">#styling-nested</feature>
-<feature value="optional">#styling-referential</feature>
-<feature value="optional">#styling</feature>
-<feature value="optional">#subFrameRate</feature>
-<feature value="optional">#textAlign-absolute</feature>
-<feature value="optional">#textAlign-relative</feature>
-<feature value="optional">#textAlign</feature>
-<feature value="optional">#textDecoration-over</feature>
-<feature value="optional">#textDecoration-through</feature>
-<feature value="optional">#textDecoration-under</feature>
-<feature value="optional">#textDecoration</feature>
-<feature value="optional">#textOutline-blurred</feature>
-<feature value="optional">#textOutline-unblurred</feature>
-<feature value="optional">#textOutline</feature>
-<feature value="optional">#tickRate</feature>
-<feature value="optional">#time-clock-with-frames</feature>
-<feature value="optional">#time-clock</feature>
-<feature value="optional">#time-offset-with-frames</feature>
-<feature value="optional">#time-offset-with-ticks</feature>
-<feature value="optional">#timeBase-clock</feature>
-<feature value="optional">#timeBase-media</feature>
-<feature value="optional">#timeBase-smpte</feature>
-<feature value="optional">#timeContainer</feature>
-<feature value="optional">#transformation</feature>
-<feature value="optional">#unicodeBidi</feature>
-<feature value="optional">#visibility-block</feature>
-<feature value="optional">#visibility-inline</feature>
-<feature value="optional">#visibility-region</feature>
-<feature value="optional">#visibility</feature>
-<feature value="optional">#wrapOption</feature>
-<feature value="optional">#writingMode-horizontal-lr</feature>
-<feature value="optional">#writingMode-horizontal-rl</feature>
-<feature value="optional">#writingMode-horizontal</feature>
-<feature value="optional">#writingMode-vertical</feature>
-<feature value="optional">#writingMode</feature>
-<feature value="optional">#zIndex</feature>
-</features>
-<extensions xml:base="http://www.w3.org/ns/ttml/extension/">
-<!-- required (mandatory) extension support -->
-<!-- optional (voluntary) extension support -->
-</extensions>
-</profile>
+<?xml version="1.0" encoding="utf-8"?>
+<!-- this file defines the "dfxp-presentation" profile of ttaf1-dfxp -->
+<profile xmlns="http://www.w3.org/ns/ttml#parameter">
+  <features xml:base="http://www.w3.org/ns/ttml/feature/">
+    <!-- required (mandatory) feature support -->
+    <feature value="required">#content</feature>
+    <feature value="required">#core</feature>
+    <feature value="required">#presentation</feature>
+    <feature value="required">#profile</feature>
+    <feature value="required">#structure</feature>
+    <feature value="required">#time-offset</feature>
+    <feature value="required">#timing</feature>
+    <!-- optional (voluntary) feature support -->
+    <feature value="optional">#animation</feature>
+    <feature value="optional">#backgroundColor-block</feature>
+    <feature value="optional">#backgroundColor-inline</feature>
+    <feature value="optional">#backgroundColor-region</feature>
+    <feature value="optional">#backgroundColor</feature>
+    <feature value="optional">#bidi</feature>
+    <feature value="optional">#cellResolution</feature>
+    <feature value="optional">#clockMode-gps</feature>
+    <feature value="optional">#clockMode-local</feature>
+    <feature value="optional">#clockMode-utc</feature>
+    <feature value="optional">#clockMode</feature>
+    <feature value="optional">#color</feature>
+    <feature value="optional">#direction</feature>
+    <feature value="optional">#display-block</feature>
+    <feature value="optional">#display-inline</feature>
+    <feature value="optional">#display-region</feature>
+    <feature value="optional">#display</feature>
+    <feature value="optional">#displayAlign</feature>
+    <feature value="optional">#dropMode-dropNTSC</feature>
+    <feature value="optional">#dropMode-dropPAL</feature>
+    <feature value="optional">#dropMode-nonDrop</feature>
+    <feature value="optional">#dropMode</feature>
+    <feature value="optional">#extent-region</feature>
+    <feature value="optional">#extent-root</feature>
+    <feature value="optional">#extent</feature>
+    <feature value="optional">#fontFamily-generic</feature>
+    <feature value="optional">#fontFamily-non-generic</feature>
+    <feature value="optional">#fontFamily</feature>
+    <feature value="optional">#fontSize-anamorphic</feature>
+    <feature value="optional">#fontSize-isomorphic</feature>
+    <feature value="optional">#fontSize</feature>
+    <feature value="optional">#fontStyle-italic</feature>
+    <feature value="optional">#fontStyle-oblique</feature>
+    <feature value="optional">#fontStyle-reverseOblique</feature>
+    <feature value="optional">#fontStyle</feature>
+    <feature value="optional">#fontWeight-bold</feature>
+    <feature value="optional">#fontWeight</feature>
+    <feature value="optional">#frameRate</feature>
+    <feature value="optional">#frameRateMultiplier</feature>
+    <feature value="optional">#layout</feature>
+    <feature value="optional">#length-cell</feature>
+    <feature value="optional">#length-em</feature>
+    <feature value="optional">#length-negative</feature>
+    <feature value="optional">#length-percentage</feature>
+    <feature value="optional">#length-pixel</feature>
+    <feature value="optional">#length-positive</feature>
+    <feature value="optional">#length-real</feature>
+    <feature value="optional">#length</feature>
+    <feature value="optional">#lineBreak-uax14</feature>
+    <feature value="optional">#lineHeight</feature>
+    <feature value="optional">#markerMode-continuous</feature>
+    <feature value="optional">#markerMode-discontinuous</feature>
+    <feature value="optional">#markerMode</feature>
+    <feature value="optional">#metadata-foreign</feature>
+    <feature value="optional">#metadata</feature>
+    <feature value="optional">#nested-div</feature>
+    <feature value="optional">#nested-span</feature>
+    <feature value="optional">#opacity</feature>
+    <feature value="optional">#origin</feature>
+    <feature value="optional">#overflow-scroll</feature>
+    <feature value="optional">#overflow-visible</feature>
+    <feature value="optional">#overflow</feature>
+    <feature value="optional">#padding-1</feature>
+    <feature value="optional">#padding-2</feature>
+    <feature value="optional">#padding-3</feature>
+    <feature value="optional">#padding-4</feature>
+    <feature value="optional">#padding</feature>
+    <feature value="optional">#pixelAspectRatio</feature>
+    <feature value="optional">#showBackground</feature>
+    <feature value="optional">#styling-chained</feature>
+    <feature value="optional">#styling-inheritance-content</feature>
+    <feature value="optional">#styling-inheritance-region</feature>
+    <feature value="optional">#styling-inline</feature>
+    <feature value="optional">#styling-nested</feature>
+    <feature value="optional">#styling-referential</feature>
+    <feature value="optional">#styling</feature>
+    <feature value="optional">#subFrameRate</feature>
+    <feature value="optional">#textAlign-absolute</feature>
+    <feature value="optional">#textAlign-relative</feature>
+    <feature value="optional">#textAlign</feature>
+    <feature value="optional">#textDecoration-over</feature>
+    <feature value="optional">#textDecoration-through</feature>
+    <feature value="optional">#textDecoration-under</feature>
+    <feature value="optional">#textDecoration</feature>
+    <feature value="optional">#textOutline-blurred</feature>
+    <feature value="optional">#textOutline-unblurred</feature>
+    <feature value="optional">#textOutline</feature>
+    <feature value="optional">#tickRate</feature>
+    <feature value="optional">#time-clock-with-frames</feature>
+    <feature value="optional">#time-clock</feature>
+    <feature value="optional">#time-offset-with-frames</feature>
+    <feature value="optional">#time-offset-with-ticks</feature>
+    <feature value="optional">#timeBase-clock</feature>
+    <feature value="optional">#timeBase-media</feature>
+    <feature value="optional">#timeBase-smpte</feature>
+    <feature value="optional">#timeContainer</feature>
+    <feature value="optional">#transformation</feature>
+    <feature value="optional">#unicodeBidi</feature>
+    <feature value="optional">#visibility-block</feature>
+    <feature value="optional">#visibility-inline</feature>
+    <feature value="optional">#visibility-region</feature>
+    <feature value="optional">#visibility</feature>
+    <feature value="optional">#wrapOption</feature>
+    <feature value="optional">#writingMode-horizontal-lr</feature>
+    <feature value="optional">#writingMode-horizontal-rl</feature>
+    <feature value="optional">#writingMode-horizontal</feature>
+    <feature value="optional">#writingMode-vertical</feature>
+    <feature value="optional">#writingMode</feature>
+    <feature value="optional">#zIndex</feature>
+  </features>
+  <extensions xml:base="http://www.w3.org/ns/ttml/extension/">
+    <!-- required (mandatory) extension support -->
+    <!-- optional (voluntary) extension support -->
+  </extensions>
+</profile>
+
--- a/spec/profiles/dfxp-transformation.xml	Thu May 13 16:55:59 2010 +0000
+++ b/spec/profiles/dfxp-transformation.xml	Mon May 31 11:23:45 2010 +0000
@@ -1,142 +1,129 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- this file defines the "dfxp-transformation" profile of ttaf1 -->
-<profile xmlns="http://www.w3.org/ns/ttml#parameter">
-<features xml:base="http://www.w3.org/ns/ttml/feature/">
-<!-- required (mandatory) feature support -->
-<feature value="required">#content</feature>
-<feature value="required">#core</feature>
-<feature value="required">#profile</feature>
-<feature value="required">#structure</feature>
-<feature value="required">#time-offset</feature>
-<feature value="required">#timing</feature>
-<feature value="required">#transformation</feature>
-<!-- optional (voluntary) feature support -->
-<feature value="optional">#animation</feature>
-<feature value="optional">#backgroundColor-block</feature>
-<feature value="optional">#backgroundColor-inline</feature>
-<feature value="optional">#backgroundColor-region</feature>
-<feature value="optional">#backgroundColor</feature>
-<feature value="optional">#bidi</feature>
-<feature value="optional">#cellResolution</feature>
-<feature value="optional">#clockMode-gps</feature>
-<feature value="optional">#clockMode-local</feature>
-<feature value="optional">#clockMode-utc</feature>
-<feature value="optional">#clockMode</feature>
-<feature value="optional">#color</feature>
-<feature value="optional">#direction</feature>
-<feature value="optional">#display-block</feature>
-<feature value="optional">#display-inline</feature>
-<feature value="optional">#display-region</feature>
-<feature value="optional">#display</feature>
-<feature value="optional">#displayAlign</feature>
-<feature value="optional">#dropMode-dropNTSC</feature>
-<feature value="optional">#dropMode-dropPAL</feature>
-<feature value="optional">#dropMode-nonDrop</feature>
-<feature value="optional">#dropMode</feature>
-<feature value="optional">#dynamicFlow-character</feature>
-<feature value="optional">#dynamicFlow-clear</feature>
-<feature value="optional">#dynamicFlow-fill</feature>
-<feature value="optional">#dynamicFlow-glyph</feature>
-<feature value="optional">#dynamicFlow-in</feature>
-<feature value="optional">#dynamicFlow-jump</feature>
-<feature value="optional">#dynamicFlow-line</feature>
-<feature value="optional">#dynamicFlow-out</feature>
-<feature value="optional">#dynamicFlow-rollUp</feature>
-<feature value="optional">#dynamicFlow-smooth</feature>
-<feature value="optional">#dynamicFlow-teletext</feature>
-<feature value="optional">#dynamicFlow-word</feature>
-<feature value="optional">#dynamicFlow</feature>
-<feature value="optional">#extent-region</feature>
-<feature value="optional">#extent-root</feature>
-<feature value="optional">#extent</feature>
-<feature value="optional">#fontFamily-generic</feature>
-<feature value="optional">#fontFamily-non-generic</feature>
-<feature value="optional">#fontFamily</feature>
-<feature value="optional">#fontSize-anamorphic</feature>
-<feature value="optional">#fontSize-isomorphic</feature>
-<feature value="optional">#fontSize</feature>
-<feature value="optional">#fontStyle-italic</feature>
-<feature value="optional">#fontStyle-oblique</feature>
-<feature value="optional">#fontStyle-reverseOblique</feature>
-<feature value="optional">#fontStyle</feature>
-<feature value="optional">#fontWeight-bold</feature>
-<feature value="optional">#fontWeight</feature>
-<feature value="optional">#frameRate</feature>
-<feature value="optional">#frameRateMultiplier</feature>
-<feature value="optional">#layout</feature>
-<feature value="optional">#length-cell</feature>
-<feature value="optional">#length-em</feature>
-<feature value="optional">#length-negative</feature>
-<feature value="optional">#length-percentage</feature>
-<feature value="optional">#length-pixel</feature>
-<feature value="optional">#length-positive</feature>
-<feature value="optional">#length-real</feature>
-<feature value="optional">#length</feature>
-<feature value="optional">#lineBreak-uax14</feature>
-<feature value="optional">#lineHeight</feature>
-<feature value="optional">#markerMode-continuous</feature>
-<feature value="optional">#markerMode-discontinuous</feature>
-<feature value="optional">#markerMode</feature>
-<feature value="optional">#metadata-foreign</feature>
-<feature value="optional">#metadata</feature>
-<feature value="optional">#nested-div</feature>
-<feature value="optional">#nested-span</feature>
-<feature value="optional">#opacity</feature>
-<feature value="optional">#origin</feature>
-<feature value="optional">#overflow-scroll</feature>
-<feature value="optional">#overflow-visible</feature>
-<feature value="optional">#overflow</feature>
-<feature value="optional">#padding-1</feature>
-<feature value="optional">#padding-2</feature>
-<feature value="optional">#padding-3</feature>
-<feature value="optional">#padding-4</feature>
-<feature value="optional">#padding</feature>
-<feature value="optional">#pixelAspectRatio</feature>
-<feature value="optional">#presentation</feature>
-<feature value="optional">#rollUp</feature>
-<feature value="optional">#showBackground</feature>
-<feature value="optional">#styling-chained</feature>
-<feature value="optional">#styling-inheritance-content</feature>
-<feature value="optional">#styling-inheritance-region</feature>
-<feature value="optional">#styling-inline</feature>
-<feature value="optional">#styling-nested</feature>
-<feature value="optional">#styling-referential</feature>
-<feature value="optional">#styling</feature>
-<feature value="optional">#subFrameRate</feature>
-<feature value="optional">#textAlign-absolute</feature>
-<feature value="optional">#textAlign-relative</feature>
-<feature value="optional">#textAlign</feature>
-<feature value="optional">#textDecoration-over</feature>
-<feature value="optional">#textDecoration-through</feature>
-<feature value="optional">#textDecoration-under</feature>
-<feature value="optional">#textDecoration</feature>
-<feature value="optional">#textOutline-blurred</feature>
-<feature value="optional">#textOutline-unblurred</feature>
-<feature value="optional">#textOutline</feature>
-<feature value="optional">#tickRate</feature>
-<feature value="optional">#time-clock-with-frames</feature>
-<feature value="optional">#time-clock</feature>
-<feature value="optional">#time-offset-with-frames</feature>
-<feature value="optional">#time-offset-with-ticks</feature>
-<feature value="optional">#timeBase-clock</feature>
-<feature value="optional">#timeBase-media</feature>
-<feature value="optional">#timeBase-smpte</feature>
-<feature value="optional">#timeContainer</feature>
-<feature value="optional">#unicodeBidi</feature>
-<feature value="optional">#visibility-block</feature>
-<feature value="optional">#visibility-inline</feature>
-<feature value="optional">#visibility-region</feature>
-<feature value="optional">#visibility</feature>
-<feature value="optional">#wrapOption</feature>
-<feature value="optional">#writingMode-horizontal-lr</feature>
-<feature value="optional">#writingMode-horizontal-rl</feature>
-<feature value="optional">#writingMode-horizontal</feature>
-<feature value="optional">#writingMode-vertical</feature>
-<feature value="optional">#writingMode</feature>
-<feature value="optional">#zIndex</feature>
-</features>
-<extensions xml:base="http://www.w3.org/ns/ttml/extension/">
-<!-- required (mandatory) extension support -->
-<!-- optional (voluntary) extension support -->
-</extensions>
-</profile>
+<?xml version="1.0" encoding="utf-8"?>
+<!-- this file defines the "dfxp-transformation" profile of ttaf1 -->
+<profile xmlns="http://www.w3.org/ns/ttml#parameter">
+  <features xml:base="http://www.w3.org/ns/ttml/feature/">
+    <!-- required (mandatory) feature support -->
+    <feature value="required">#content</feature>
+    <feature value="required">#core</feature>
+    <feature value="required">#profile</feature>
+    <feature value="required">#structure</feature>
+    <feature value="required">#time-offset</feature>
+    <feature value="required">#timing</feature>
+    <feature value="required">#transformation</feature>
+    <!-- optional (voluntary) feature support -->
+    <feature value="optional">#animation</feature>
+    <feature value="optional">#backgroundColor-block</feature>
+    <feature value="optional">#backgroundColor-inline</feature>
+    <feature value="optional">#backgroundColor-region</feature>
+    <feature value="optional">#backgroundColor</feature>
+    <feature value="optional">#bidi</feature>
+    <feature value="optional">#cellResolution</feature>
+    <feature value="optional">#clockMode-gps</feature>
+    <feature value="optional">#clockMode-local</feature>
+    <feature value="optional">#clockMode-utc</feature>
+    <feature value="optional">#clockMode</feature>
+    <feature value="optional">#color</feature>
+    <feature value="optional">#direction</feature>
+    <feature value="optional">#display-block</feature>
+    <feature value="optional">#display-inline</feature>
+    <feature value="optional">#display-region</feature>
+    <feature value="optional">#display</feature>
+    <feature value="optional">#displayAlign</feature>
+    <feature value="optional">#dropMode-dropNTSC</feature>
+    <feature value="optional">#dropMode-dropPAL</feature>
+    <feature value="optional">#dropMode-nonDrop</feature>
+    <feature value="optional">#dropMode</feature>
+    <feature value="optional">#extent-region</feature>
+    <feature value="optional">#extent-root</feature>
+    <feature value="optional">#extent</feature>
+    <feature value="optional">#fontFamily-generic</feature>
+    <feature value="optional">#fontFamily-non-generic</feature>
+    <feature value="optional">#fontFamily</feature>
+    <feature value="optional">#fontSize-anamorphic</feature>
+    <feature value="optional">#fontSize-isomorphic</feature>
+    <feature value="optional">#fontSize</feature>
+    <feature value="optional">#fontStyle-italic</feature>
+    <feature value="optional">#fontStyle-oblique</feature>
+    <feature value="optional">#fontStyle-reverseOblique</feature>
+    <feature value="optional">#fontStyle</feature>
+    <feature value="optional">#fontWeight-bold</feature>
+    <feature value="optional">#fontWeight</feature>
+    <feature value="optional">#frameRate</feature>
+    <feature value="optional">#frameRateMultiplier</feature>
+    <feature value="optional">#layout</feature>
+    <feature value="optional">#length-cell</feature>
+    <feature value="optional">#length-em</feature>
+    <feature value="optional">#length-negative</feature>
+    <feature value="optional">#length-percentage</feature>
+    <feature value="optional">#length-pixel</feature>
+    <feature value="optional">#length-positive</feature>
+    <feature value="optional">#length-real</feature>
+    <feature value="optional">#length</feature>
+    <feature value="optional">#lineBreak-uax14</feature>
+    <feature value="optional">#lineHeight</feature>
+    <feature value="optional">#markerMode-continuous</feature>
+    <feature value="optional">#markerMode-discontinuous</feature>
+    <feature value="optional">#markerMode</feature>
+    <feature value="optional">#metadata-foreign</feature>
+    <feature value="optional">#metadata</feature>
+    <feature value="optional">#nested-div</feature>
+    <feature value="optional">#nested-span</feature>
+    <feature value="optional">#opacity</feature>
+    <feature value="optional">#origin</feature>
+    <feature value="optional">#overflow-scroll</feature>
+    <feature value="optional">#overflow-visible</feature>
+    <feature value="optional">#overflow</feature>
+    <feature value="optional">#padding-1</feature>
+    <feature value="optional">#padding-2</feature>
+    <feature value="optional">#padding-3</feature>
+    <feature value="optional">#padding-4</feature>
+    <feature value="optional">#padding</feature>
+    <feature value="optional">#pixelAspectRatio</feature>
+    <feature value="optional">#presentation</feature>
+    <feature value="optional">#showBackground</feature>
+    <feature value="optional">#styling-chained</feature>
+    <feature value="optional">#styling-inheritance-content</feature>
+    <feature value="optional">#styling-inheritance-region</feature>
+    <feature value="optional">#styling-inline</feature>
+    <feature value="optional">#styling-nested</feature>
+    <feature value="optional">#styling-referential</feature>
+    <feature value="optional">#styling</feature>
+    <feature value="optional">#subFrameRate</feature>
+    <feature value="optional">#textAlign-absolute</feature>
+    <feature value="optional">#textAlign-relative</feature>
+    <feature value="optional">#textAlign</feature>
+    <feature value="optional">#textDecoration-over</feature>
+    <feature value="optional">#textDecoration-through</feature>
+    <feature value="optional">#textDecoration-under</feature>
+    <feature value="optional">#textDecoration</feature>
+    <feature value="optional">#textOutline-blurred</feature>
+    <feature value="optional">#textOutline-unblurred</feature>
+    <feature value="optional">#textOutline</feature>
+    <feature value="optional">#tickRate</feature>
+    <feature value="optional">#time-clock-with-frames</feature>
+    <feature value="optional">#time-clock</feature>
+    <feature value="optional">#time-offset-with-frames</feature>
+    <feature value="optional">#time-offset-with-ticks</feature>
+    <feature value="optional">#timeBase-clock</feature>
+    <feature value="optional">#timeBase-media</feature>
+    <feature value="optional">#timeBase-smpte</feature>
+    <feature value="optional">#timeContainer</feature>
+    <feature value="optional">#unicodeBidi</feature>
+    <feature value="optional">#visibility-block</feature>
+    <feature value="optional">#visibility-inline</feature>
+    <feature value="optional">#visibility-region</feature>
+    <feature value="optional">#visibility</feature>
+    <feature value="optional">#wrapOption</feature>
+    <feature value="optional">#writingMode-horizontal-lr</feature>
+    <feature value="optional">#writingMode-horizontal-rl</feature>
+    <feature value="optional">#writingMode-horizontal</feature>
+    <feature value="optional">#writingMode-vertical</feature>
+    <feature value="optional">#writingMode</feature>
+    <feature value="optional">#zIndex</feature>
+  </features>
+  <extensions xml:base="http://www.w3.org/ns/ttml/extension/">
+    <!-- required (mandatory) extension support -->
+    <!-- optional (voluntary) extension support -->
+  </extensions>
+</profile>
+
--- a/spec/rnc/ttaf1-dfxp-datatypes.rnc	Thu May 13 16:55:59 2010 +0000
+++ b/spec/rnc/ttaf1-dfxp-datatypes.rnc	Mon May 31 11:23:45 2010 +0000
@@ -37,9 +37,6 @@
   "dropPAL" |
   "nonDrop"
 
-TTAF.DynamicFlow.datatype =
-  string
-
 TTAF.ExtensionDesignator.datatype =
   TTAF.URI.datatype
 
@@ -132,8 +129,7 @@
 
 TTAF.Overflow.datatype =
   "visible" |
-  "hidden" |
-  "dynamic"
+  "hidden" 
 
 TTAF.Padding.datatype =
   string
@@ -226,3 +222,4 @@
 # .......................................................................
 # .......................................................................
 # .......................................................................
+
--- a/spec/rnc/ttaf1-dfxp-styling-attribs.rnc	Thu May 13 16:55:59 2010 +0000
+++ b/spec/rnc/ttaf1-dfxp-styling-attribs.rnc	Mon May 31 11:23:45 2010 +0000
@@ -18,8 +18,6 @@
   = attribute tts:display { TTAF.Display.datatype }?
 TTAF.displayAlign.attrib
   = attribute tts:displayAlign { TTAF.DisplayAlign.datatype }?
-TTAF.dynamicFlow.attrib
-  = attribute tts:dynamicFlow { TTAF.DynamicFlow.datatype }?
 TTAF.extent.attrib
   = attribute tts:extent { TTAF.Extent.datatype }?
 TTAF.fontFamily.attrib
@@ -72,7 +70,6 @@
   TTAF.direction.attrib,
   TTAF.display.attrib,
   TTAF.displayAlign.attrib,
-  TTAF.dynamicFlow.attrib,
   TTAF.extent.attrib,
   TTAF.fontFamily.attrib,
   TTAF.fontSize.attrib,
--- a/spec/rnc/ttaf1-dfxp-styling.rnc	Thu May 13 16:55:59 2010 +0000
+++ b/spec/rnc/ttaf1-dfxp-styling.rnc	Mon May 31 11:23:45 2010 +0000
@@ -37,8 +37,7 @@
 
 TTAF.styling.style.content.extra = empty
 TTAF.styling.style.content =
-  (TTAF.Metadata.class*,
-   (TTAF.styling.style.content.extra)*)
+  (TTAF.styling.style.content.extra)*
 
 # style definitions class
 TTAF.styling.defs.extra = empty
@@ -48,4 +47,4 @@
 
 # .......................................................................
 # .......................................................................
-# .......................................................................
+# .......................................................................
\ No newline at end of file
--- a/spec/ttaf1-dfxp.html	Thu May 13 16:55:59 2010 +0000
+++ b/spec/ttaf1-dfxp.html	Mon May 31 11:23:45 2010 +0000
@@ -417,11 +417,11 @@
 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/>
-    J.1 <a href="#d3e17024">Element Derivation</a><br/>
-    J.2 <a href="#d3e17503">Attribute Derivation</a><br/>
+    J.1 <a href="#d3e17015">Element Derivation</a><br/>
+    J.2 <a href="#d3e17494">Attribute Derivation</a><br/>
 K <a href="#qa">QA Framework Compliance</a> (Non-Normative)<br/>
-    K.1 <a href="#d3e18391">Requirements</a><br/>
-    K.2 <a href="#d3e18555">Guidelines</a><br/>
+    K.1 <a href="#d3e18382">Requirements</a><br/>
+    K.2 <a href="#d3e18546">Guidelines</a><br/>
 L <a href="#streaming">Streaming TTML Content</a> (Non-Normative)<br/>
 M <a href="#acknowledgments">Acknowledgments</a> (Non-Normative)<br/>
 N <a href="#change-history">Change History</a> (Non-Normative)<br/>
@@ -432,6 +432,7 @@
 Working Draft</a><br/>
     N.4 <a href="#change-history-lc3-to-cr2">Changes from Third Last Call Working Draft to Second Candidate Recommendation</a><br/>
     N.5 <a href="#change-history-cr2-to-cr3">Changes from Second Candidate Recommendation to Third Candidate Recommendation</a><br/>
+    N.6 <a href="#change-history-cr3-to-cr4">Changes from Third Candidate Recommendation to Fourth Candidate Recommendation</a><br/>
 </p></div><hr/><div class="body"><div class="div1">
 <h2><a name="intro" id="intro"/>1 Introduction</h2><p><em>Unless specified otherwise, this section and its sub-sections are non-normative.</em></p><p>The Timed Text Markup Language (TTML) 1.0
 provides a standardized representation of a particular subset of
@@ -929,7 +930,7 @@
 default XMLNS binding on the <code>profile</code> element to the TT Parameter Namespace.</p></div></div><div class="div2">
 <h3><a name="vocabulary-overview" id="vocabulary-overview"/>5.3 Catalog</h3><p>The vocabulary of the Timed Text Markup Language (TTML) is
 defined in the following major catalogs (divisions of vocabulary):</p><ul><li><p><a href="#core-vocabulary-overview"><b>5.3.1 Core Catalog</b></a></p></li><li><p><a href="#extension-vocabulary-overview"><b>5.3.2 Extension Catalog</b></a></p></li></ul><p>The core catalog defines the baseline, core vocabulary of TTML,
-and, in particular, the vocabulary of DFXP. The extension catalog
+and, in particular, the vocabulary of DFXP Content. The extension catalog
 serves as a placeholder for extensions to the core vocabulary defined
 by TTML.</p><div class="div3">
 <h4><a name="core-vocabulary-overview" id="core-vocabulary-overview"/>5.3.1 Core Catalog</h4><p>The core vocabulary catalog is intended to satisfy the needs of
@@ -5009,9 +5010,6 @@
   "dropPAL" |
   "nonDrop"
 
-TTAF.DynamicFlow.datatype =
-  string
-
 TTAF.ExtensionDesignator.datatype =
   TTAF.URI.datatype
 
@@ -5104,8 +5102,7 @@
 
 TTAF.Overflow.datatype =
   "visible" |
-  "hidden" |
-  "dynamic"
+  "hidden" 
 
 TTAF.Padding.datatype =
   string
@@ -5198,6 +5195,7 @@
 # .......................................................................
 # .......................................................................
 # .......................................................................
+
 </pre></div></div><div class="div4">
 <h5><a name="rnc-dfxp-document-module" id="rnc-dfxp-document-module"/>B.1.2.6 Document Module</h5><div class="exampleInner"><pre># .......................................................................
 # TT-AF 1.0 DFXP Document Module ........................................
@@ -5646,8 +5644,6 @@
   = attribute tts:display { TTAF.Display.datatype }?
 TTAF.displayAlign.attrib
   = attribute tts:displayAlign { TTAF.DisplayAlign.datatype }?
-TTAF.dynamicFlow.attrib
-  = attribute tts:dynamicFlow { TTAF.DynamicFlow.datatype }?
 TTAF.extent.attrib
   = attribute tts:extent { TTAF.Extent.datatype }?
 TTAF.fontFamily.attrib
@@ -5700,7 +5696,6 @@
   TTAF.direction.attrib,
   TTAF.display.attrib,
   TTAF.displayAlign.attrib,
-  TTAF.dynamicFlow.attrib,
   TTAF.extent.attrib,
   TTAF.fontFamily.attrib,
   TTAF.fontSize.attrib,
@@ -5777,8 +5772,7 @@
 
 TTAF.styling.style.content.extra = empty
 TTAF.styling.style.content =
-  (TTAF.Metadata.class*,
-   (TTAF.styling.style.content.extra)*)
+  (TTAF.styling.style.content.extra)*
 
 # style definitions class
 TTAF.styling.defs.extra = empty
@@ -5788,8 +5782,7 @@
 
 # .......................................................................
 # .......................................................................
-# .......................................................................
-</pre></div></div><div class="div4">
+# .......................................................................</pre></div></div><div class="div4">
 <h5><a name="rnc-dfxp-timing-attribs-module" id="rnc-dfxp-timing-attribs-module"/>B.1.2.17 Timing Attributes Module</h5><div class="exampleInner"><pre># .......................................................................
 # TT-AF 1.0 DFXP Timing Attributes Module ...............................
 # .......................................................................
@@ -6014,9 +6007,10 @@
   &lt;/xs:attributeGroup&gt;
 &lt;/xs:schema&gt;
 </pre></div></div><div class="div4">
-<h5><a name="xsd-dfxp-datatypes-module" id="xsd-dfxp-datatypes-module"/>B.2.2.4 Data Types Module</h5><div class="exampleInner"><pre>&lt;xs:schema targetNamespace="http://www.w3.org/ns/ttml#datatype"
-	xml:lang="en" xmlns:xs="http://www.w3.org/2001/XMLSchema"
-	xmlns:ttd="http://www.w3.org/ns/ttml#datatype"&gt;
+<h5><a name="xsd-dfxp-datatypes-module" id="xsd-dfxp-datatypes-module"/>B.2.2.4 Data Types Module</h5><div class="exampleInner"><pre>&lt;?xml version="1.0" encoding="utf-8"?&gt;
+&lt;xs:schema targetNamespace="http://www.w3.org/ns/ttml#datatype"
+        xml:lang="en" xmlns:xs="http://www.w3.org/2001/XMLSchema"
+        xmlns:ttd="http://www.w3.org/ns/ttml#datatype"&gt;
   &lt;xs:simpleType name="alpha"&gt;
     &lt;xs:restriction base="xs:float"&gt;
       &lt;xs:minInclusive value="0"/&gt;
@@ -6068,9 +6062,6 @@
       &lt;xs:enumeration value="nonDrop"/&gt;
     &lt;/xs:restriction&gt;
   &lt;/xs:simpleType&gt;
-  &lt;xs:simpleType name="dynamicFlow"&gt;
-    &lt;xs:restriction base="xs:string"/&gt;
-  &lt;/xs:simpleType&gt;
   &lt;xs:simpleType name="extensionDesignator"&gt;
     &lt;xs:restriction base="xs:anyURI"/&gt;
   &lt;/xs:simpleType&gt;
@@ -6201,7 +6192,6 @@
     &lt;xs:restriction base="xs:token"&gt;
       &lt;xs:enumeration value="visible"/&gt;
       &lt;xs:enumeration value="hidden"/&gt;
-      &lt;xs:enumeration value="dynamic"/&gt;
     &lt;/xs:restriction&gt;
   &lt;/xs:simpleType&gt;
   &lt;xs:simpleType name="padding"&gt;
@@ -6327,6 +6317,8 @@
     &lt;xs:restriction base="xs:string"/&gt;
   &lt;/xs:simpleType&gt;
 &lt;/xs:schema&gt;
+
+
 </pre></div></div><div class="div4">
 <h5><a name="xsd-dfxp-document-module" id="xsd-dfxp-document-module"/>B.2.2.5 Document Module</h5><div class="exampleInner"><pre>&lt;xs:schema targetNamespace="http://www.w3.org/ns/ttml" xml:lang="en"
   xmlns:xs="http://www.w3.org/2001/XMLSchema"
@@ -6659,7 +6651,8 @@
   &lt;/xs:attributeGroup&gt;
 &lt;/xs:schema&gt;
 </pre></div></div><div class="div4">
-<h5><a name="xsd-dfxp-styling-attribs-module" id="xsd-dfxp-styling-attribs-module"/>B.2.2.14 Styling Attributes Module</h5><div class="exampleInner"><pre>&lt;xs:schema targetNamespace="http://www.w3.org/ns/ttml#styling" xml:lang="en"
+<h5><a name="xsd-dfxp-styling-attribs-module" id="xsd-dfxp-styling-attribs-module"/>B.2.2.14 Styling Attributes Module</h5><div class="exampleInner"><pre>&lt;?xml version="1.0" encoding="utf-8"?&gt;
+&lt;xs:schema targetNamespace="http://www.w3.org/ns/ttml#styling" xml:lang="en"
   xmlns:xs="http://www.w3.org/2001/XMLSchema"
   xmlns:ttd="http://www.w3.org/ns/ttml#datatype"
   xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
@@ -6670,7 +6663,6 @@
   &lt;xs:attribute name="direction" type="ttd:direction"/&gt;
   &lt;xs:attribute name="display" type="ttd:display"/&gt;
   &lt;xs:attribute name="displayAlign" type="ttd:displayAlign"/&gt;
-  &lt;xs:attribute name="dynamicFlow" type="ttd:dynamicFlow"/&gt;
   &lt;xs:attribute name="extent" type="ttd:extent"/&gt;
   &lt;xs:attribute name="fontFamily" type="ttd:fontFamily"/&gt;
   &lt;xs:attribute name="fontSize" type="ttd:fontSize"/&gt;
@@ -6696,7 +6688,6 @@
     &lt;xs:attribute ref="tts:direction"/&gt;
     &lt;xs:attribute ref="tts:display"/&gt;
     &lt;xs:attribute ref="tts:displayAlign"/&gt;
-    &lt;xs:attribute ref="tts:dynamicFlow"/&gt;
     &lt;xs:attribute ref="tts:extent"/&gt;
     &lt;xs:attribute ref="tts:fontFamily"/&gt;
     &lt;xs:attribute ref="tts:fontSize"/&gt;
@@ -6718,6 +6709,7 @@
     &lt;xs:attribute ref="tts:zIndex"/&gt;
   &lt;/xs:attributeGroup&gt;
 &lt;/xs:schema&gt;
+
 </pre></div></div><div class="div4">
 <h5><a name="xsd-dfxp-styling-module" id="xsd-dfxp-styling-module"/>B.2.2.15 Styling Module</h5><div class="exampleInner"><pre>&lt;xs:schema targetNamespace="http://www.w3.org/ns/ttml" xml:lang="en"
   xmlns:xs="http://www.w3.org/2001/XMLSchema"
@@ -6750,14 +6742,13 @@
     &lt;xs:attributeGroup ref="tt:styling.attlist"/&gt;
   &lt;/xs:complexType&gt;
   &lt;xs:complexType name="style.eltype"&gt;
-    &lt;xs:sequence&gt;
-      &lt;xs:group ref="tt:Metadata.class" minOccurs="0" maxOccurs="unbounded"/&gt;
-    &lt;/xs:sequence&gt;
     &lt;xs:attributeGroup ref="tt:style.attlist"/&gt;
   &lt;/xs:complexType&gt;
   &lt;xs:element name="styling" type="tt:styling.eltype"/&gt;
   &lt;xs:element name="style" type="tt:style.eltype"/&gt;
 &lt;/xs:schema&gt;
+
+
 </pre></div></div><div class="div4">
 <h5><a name="xsd-dfxp-timing-attribs-module" id="xsd-dfxp-timing-attribs-module"/>B.2.2.16 Timing Attributes Module</h5><div class="exampleInner"><pre>&lt;xs:schema targetNamespace="http://www.w3.org/ns/ttml" xml:lang="en"
   xmlns:xs="http://www.w3.org/2001/XMLSchema"
@@ -7713,7 +7704,7 @@
 enumerates every defined feature designation (expressed without the TT
 Feature Namespace), and, for each designated feature, specifies
 whether the feature is mandatory (M) or optional (O) for
-transformation and presentation processors.</p><table summary="HTML Table" id="feature-support-table" class="common"><caption>Table E-1 – Feature Support</caption><col width="60%" span="1"/><col width="20%" span="1"/><col width="20%" span="1"/><tbody><tr><td><span class="strong">Feature</span></td><td><span class="strong">Transformation</span></td><td><span class="strong">Presentation</span></td></tr><tr><td><a href="#feature-animation"><code>#animation</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-backgroundColor"><code>#backgroundColor</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-backgroundColor-block"><code>#backgroundColor-block</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-backgroundColor-inline"><code>#backgroundColor-inline</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-backgroundColor-region"><code>#backgroundColor-region</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-bidi"><code>#bidi</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-cellResolution"><code>#cellResolution</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-clockMode"><code>#clockMode</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-clockMode-gps"><code>#clockMode-gps</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-clockMode-local"><code>#clockMode-local</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-clockMode-utc"><code>#clockMode-utc</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-color"><code>#color</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-content"><code>#content</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-core"><code>#core</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-direction"><code>#direction</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-display"><code>#display</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-display-block"><code>#display-block</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-display-inline"><code>#display-inline</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-display-region"><code>#display-region</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-displayAlign"><code>#displayAlign</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-dropMode"><code>#dropMode</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-dropMode-dropNTSC"><code>#dropMode-dropNTSC</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-dropMode-dropPAL"><code>#dropMode-dropPAL</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-dropMode-nonDrop"><code>#dropMode-nonDrop</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-extent"><code>#extent</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-extent-region"><code>#extent-region</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-extent-root"><code>#extent-root</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontFamily"><code>#fontFamily</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontFamily-generic"><code>#fontFamily-generic</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontFamily-non-generic"><code>#fontFamily-non-generic</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontSize"><code>#fontSize</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontSize-anamorphic"><code>#fontSize-anamorphic</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontSize-isomorphic"><code>#fontSize-isomorphic</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontStyle"><code>#fontStyle</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontStyle-italic"><code>#fontStyle-italic</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontStyle-oblique"><code>#fontStyle-oblique</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontStyle-reverseOblique"><code>#fontStyle-reverseOblique</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontWeight"><code>#fontWeight</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontWeight-bold"><code>#fontWeight-bold</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-frameRate"><code>#frameRate</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-frameRateMultiplier"><code>#frameRateMultiplier</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-layout"><code>#layout</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length"><code>#length</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-cell"><code>#length-cell</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-em"><code>#length-em</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-integer"><code>#length-integer</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-negative"><code>#length-negative</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-percentage"><code>#length-percentage</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-pixel"><code>#length-pixel</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-positive"><code>#length-positive</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-real"><code>#length-real</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-lineBreak-uax14"><code>#lineBreak-uax14</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-lineHeight"><code>#lineHeight</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-markerMode"><code>#markerMode</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-markerMode-continuous"><code>#markerMode-continuous</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-markerMode-discontinuous"><code>#markerMode-discontinuous</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-metadata"><code>#metadata</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-nested-div"><code>#nested-div</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-nested-span"><code>#nested-span</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-opacity"><code>#opacity</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-origin"><code>#origin</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-overflow"><code>#overflow</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-overflow-visible"><code>#overflow-visible</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-padding"><code>#padding</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-padding-1"><code>#padding-1</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-padding-2"><code>#padding-2</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-padding-3"><code>#padding-3</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-padding-4"><code>#padding-4</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-pixelAspectRatio"><code>#pixelAspectRatio</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-presentation"><code>#presentation</code></a></td><td>O</td><td>M</td></tr><tr><td><a href="#feature-profile"><code>#profile</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-rollUp"><code>#rollUp</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-showBackground"><code>#showBackground</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-structure"><code>#structure</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-styling"><code>#styling</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-chained"><code>#styling-chained</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-inheritance-content"><code>#styling-inheritance-content</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-inheritance-region"><code>#styling-inheritance-region</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-inline"><code>#styling-inline</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-nested"><code>#styling-nested</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-referential"><code>#styling-referential</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-subFrameRate"><code>#subFrameRate</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textAlign"><code>#textAlign</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textAlign-absolute"><code>#textAlign-absolute</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textAlign-relative"><code>#textAlign-relative</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textDecoration"><code>#textDecoration</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textDecoration-over"><code>#textDecoration-over</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textDecoration-through"><code>#textDecoration-through</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textDecoration-under"><code>#textDecoration-under</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textOutline"><code>#textOutline</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textOutline-blurred"><code>#textOutline-blurred</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textOutline-unblurred"><code>#textOutline-unblurred</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-tickRate"><code>#tickRate</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-timeBase-clock"><code>#timeBase-clock</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-timeBase-media"><code>#timeBase-media</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-timeBase-smpte"><code>#timeBase-smpte</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-timeContainer"><code>#timeContainer</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-time-clock"><code>#time-clock</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-time-clock-with-frames"><code>#time-clock-with-frames</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-time-offset"><code>#time-offset</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-time-offset-with-frames"><code>#time-offset-with-frames</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-time-offset-with-ticks"><code>#time-offset-with-ticks</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-timing"><code>#timing</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-transformation"><code>#transformation</code></a></td><td>M</td><td>O</td></tr><tr><td><a href="#feature-unicodeBidi"><code>#unicodeBidi</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-visibility"><code>#visibility</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-visibility-block"><code>#visibility-block</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-visibility-inline"><code>#visibility-inline</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-visibility-region"><code>#visibility-region</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-wrapOption"><code>#wrapOption</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-writingMode"><code>#writingMode</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-writingMode-vertical"><code>#writingMode-vertical</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-writingMode-horizontal"><code>#writingMode-horizontal</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-writingMode-horizontal-lr"><code>#writingMode-horizontal-lr</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-writingMode-horizontal-rl"><code>#writingMode-horizontal-rl</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-zIndex"><code>#zIndex</code></a></td><td>O</td><td>O</td></tr></tbody></table><p>For the sake of convenience, the following table,
+transformation and presentation processors.</p><table summary="HTML Table" id="feature-support-table" class="common"><caption>Table E-1 – Feature Support</caption><col width="60%" span="1"/><col width="20%" span="1"/><col width="20%" span="1"/><tbody><tr><td><span class="strong">Feature</span></td><td><span class="strong">Transformation</span></td><td><span class="strong">Presentation</span></td></tr><tr><td><a href="#feature-animation"><code>#animation</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-backgroundColor"><code>#backgroundColor</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-backgroundColor-block"><code>#backgroundColor-block</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-backgroundColor-inline"><code>#backgroundColor-inline</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-backgroundColor-region"><code>#backgroundColor-region</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-bidi"><code>#bidi</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-cellResolution"><code>#cellResolution</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-clockMode"><code>#clockMode</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-clockMode-gps"><code>#clockMode-gps</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-clockMode-local"><code>#clockMode-local</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-clockMode-utc"><code>#clockMode-utc</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-color"><code>#color</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-content"><code>#content</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-core"><code>#core</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-direction"><code>#direction</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-display"><code>#display</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-display-block"><code>#display-block</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-display-inline"><code>#display-inline</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-display-region"><code>#display-region</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-displayAlign"><code>#displayAlign</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-dropMode"><code>#dropMode</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-dropMode-dropNTSC"><code>#dropMode-dropNTSC</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-dropMode-dropPAL"><code>#dropMode-dropPAL</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-dropMode-nonDrop"><code>#dropMode-nonDrop</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-extent"><code>#extent</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-extent-region"><code>#extent-region</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-extent-root"><code>#extent-root</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontFamily"><code>#fontFamily</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontFamily-generic"><code>#fontFamily-generic</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontFamily-non-generic"><code>#fontFamily-non-generic</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontSize"><code>#fontSize</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontSize-anamorphic"><code>#fontSize-anamorphic</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontSize-isomorphic"><code>#fontSize-isomorphic</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontStyle"><code>#fontStyle</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontStyle-italic"><code>#fontStyle-italic</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontStyle-oblique"><code>#fontStyle-oblique</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontStyle-reverseOblique"><code>#fontStyle-reverseOblique</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontWeight"><code>#fontWeight</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-fontWeight-bold"><code>#fontWeight-bold</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-frameRate"><code>#frameRate</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-frameRateMultiplier"><code>#frameRateMultiplier</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-layout"><code>#layout</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length"><code>#length</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-cell"><code>#length-cell</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-em"><code>#length-em</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-integer"><code>#length-integer</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-negative"><code>#length-negative</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-percentage"><code>#length-percentage</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-pixel"><code>#length-pixel</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-positive"><code>#length-positive</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-length-real"><code>#length-real</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-lineBreak-uax14"><code>#lineBreak-uax14</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-lineHeight"><code>#lineHeight</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-markerMode"><code>#markerMode</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-markerMode-continuous"><code>#markerMode-continuous</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-markerMode-discontinuous"><code>#markerMode-discontinuous</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-metadata"><code>#metadata</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-nested-div"><code>#nested-div</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-nested-span"><code>#nested-span</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-opacity"><code>#opacity</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-origin"><code>#origin</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-overflow"><code>#overflow</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-overflow-visible"><code>#overflow-visible</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-padding"><code>#padding</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-padding-1"><code>#padding-1</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-padding-2"><code>#padding-2</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-padding-3"><code>#padding-3</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-padding-4"><code>#padding-4</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-pixelAspectRatio"><code>#pixelAspectRatio</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-presentation"><code>#presentation</code></a></td><td>O</td><td>M</td></tr><tr><td><a href="#feature-profile"><code>#profile</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-showBackground"><code>#showBackground</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-structure"><code>#structure</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-styling"><code>#styling</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-chained"><code>#styling-chained</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-inheritance-content"><code>#styling-inheritance-content</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-inheritance-region"><code>#styling-inheritance-region</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-inline"><code>#styling-inline</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-nested"><code>#styling-nested</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-styling-referential"><code>#styling-referential</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-subFrameRate"><code>#subFrameRate</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textAlign"><code>#textAlign</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textAlign-absolute"><code>#textAlign-absolute</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textAlign-relative"><code>#textAlign-relative</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textDecoration"><code>#textDecoration</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textDecoration-over"><code>#textDecoration-over</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textDecoration-through"><code>#textDecoration-through</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textDecoration-under"><code>#textDecoration-under</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textOutline"><code>#textOutline</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textOutline-blurred"><code>#textOutline-blurred</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-textOutline-unblurred"><code>#textOutline-unblurred</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-tickRate"><code>#tickRate</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-timeBase-clock"><code>#timeBase-clock</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-timeBase-media"><code>#timeBase-media</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-timeBase-smpte"><code>#timeBase-smpte</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-timeContainer"><code>#timeContainer</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-time-clock"><code>#time-clock</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-time-clock-with-frames"><code>#time-clock-with-frames</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-time-offset"><code>#time-offset</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-time-offset-with-frames"><code>#time-offset-with-frames</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-time-offset-with-ticks"><code>#time-offset-with-ticks</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-timing"><code>#timing</code></a></td><td>M</td><td>M</td></tr><tr><td><a href="#feature-transformation"><code>#transformation</code></a></td><td>M</td><td>O</td></tr><tr><td><a href="#feature-unicodeBidi"><code>#unicodeBidi</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-visibility"><code>#visibility</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-visibility-block"><code>#visibility-block</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-visibility-inline"><code>#visibility-inline</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-visibility-region"><code>#visibility-region</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-wrapOption"><code>#wrapOption</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-writingMode"><code>#writingMode</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-writingMode-vertical"><code>#writingMode-vertical</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-writingMode-horizontal"><code>#writingMode-horizontal</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-writingMode-horizontal-lr"><code>#writingMode-horizontal-lr</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-writingMode-horizontal-rl"><code>#writingMode-horizontal-rl</code></a></td><td>O</td><td>O</td></tr><tr><td><a href="#feature-zIndex"><code>#zIndex</code></a></td><td>O</td><td>O</td></tr></tbody></table><p>For the sake of convenience, the following table,
 <a href="#feature-transformation-mandatory-table"><b>Table E-2 – Mandatory Features - Transformation</b></a>, enumerates all
 mandatory features for a TTML Transformation Processor, providing additional
 comments to summarize the context of usage or the nature of the feature.
@@ -7795,433 +7786,394 @@
 express minimum compliance for transformation processing.</p><div class="exampleInner"><pre>&lt;?xml version="1.0" encoding="utf-8"?&gt;
 &lt;!-- this file defines the "dfxp-transformation" profile of ttaf1 --&gt;
 &lt;profile xmlns="http://www.w3.org/ns/ttml#parameter"&gt;
-&lt;features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
-&lt;!-- required (mandatory) feature support --&gt;
-&lt;feature value="required"&gt;#content&lt;/feature&gt;
-&lt;feature value="required"&gt;#core&lt;/feature&gt;
-&lt;feature value="required"&gt;#profile&lt;/feature&gt;
-&lt;feature value="required"&gt;#structure&lt;/feature&gt;
-&lt;feature value="required"&gt;#time-offset&lt;/feature&gt;
-&lt;feature value="required"&gt;#timing&lt;/feature&gt;
-&lt;feature value="required"&gt;#transformation&lt;/feature&gt;
-&lt;!-- optional (voluntary) feature support --&gt;
-&lt;feature value="optional"&gt;#animation&lt;/feature&gt;
-&lt;feature value="optional"&gt;#backgroundColor-block&lt;/feature&gt;
-&lt;feature value="optional"&gt;#backgroundColor-inline&lt;/feature&gt;
-&lt;feature value="optional"&gt;#backgroundColor-region&lt;/feature&gt;
-&lt;feature value="optional"&gt;#backgroundColor&lt;/feature&gt;
-&lt;feature value="optional"&gt;#bidi&lt;/feature&gt;
-&lt;feature value="optional"&gt;#cellResolution&lt;/feature&gt;
-&lt;feature value="optional"&gt;#clockMode-gps&lt;/feature&gt;
-&lt;feature value="optional"&gt;#clockMode-local&lt;/feature&gt;
-&lt;feature value="optional"&gt;#clockMode-utc&lt;/feature&gt;
-&lt;feature value="optional"&gt;#clockMode&lt;/feature&gt;
-&lt;feature value="optional"&gt;#color&lt;/feature&gt;
-&lt;feature value="optional"&gt;#direction&lt;/feature&gt;
-&lt;feature value="optional"&gt;#display-block&lt;/feature&gt;
-&lt;feature value="optional"&gt;#display-inline&lt;/feature&gt;
-&lt;feature value="optional"&gt;#display-region&lt;/feature&gt;
-&lt;feature value="optional"&gt;#display&lt;/feature&gt;
-&lt;feature value="optional"&gt;#displayAlign&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dropMode-dropNTSC&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dropMode-dropPAL&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dropMode-nonDrop&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dropMode&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-character&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-clear&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-fill&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-glyph&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-in&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-jump&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-line&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-out&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-rollUp&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-smooth&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-teletext&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-word&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow&lt;/feature&gt;
-&lt;feature value="optional"&gt;#extent-region&lt;/feature&gt;
-&lt;feature value="optional"&gt;#extent-root&lt;/feature&gt;
-&lt;feature value="optional"&gt;#extent&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontFamily-generic&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontFamily-non-generic&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontFamily&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontSize-anamorphic&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontSize-isomorphic&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontSize&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontStyle-italic&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontStyle-oblique&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontStyle-reverseOblique&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontStyle&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontWeight-bold&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontWeight&lt;/feature&gt;
-&lt;feature value="optional"&gt;#frameRate&lt;/feature&gt;
-&lt;feature value="optional"&gt;#frameRateMultiplier&lt;/feature&gt;
-&lt;feature value="optional"&gt;#layout&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-cell&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-em&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-negative&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-percentage&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-pixel&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-positive&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-real&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length&lt;/feature&gt;
-&lt;feature value="optional"&gt;#lineBreak-uax14&lt;/feature&gt;
-&lt;feature value="optional"&gt;#lineHeight&lt;/feature&gt;
-&lt;feature value="optional"&gt;#markerMode-continuous&lt;/feature&gt;
-&lt;feature value="optional"&gt;#markerMode-discontinuous&lt;/feature&gt;
-&lt;feature value="optional"&gt;#markerMode&lt;/feature&gt;
-&lt;feature value="optional"&gt;#metadata-foreign&lt;/feature&gt;
-&lt;feature value="optional"&gt;#metadata&lt;/feature&gt;
-&lt;feature value="optional"&gt;#nested-div&lt;/feature&gt;
-&lt;feature value="optional"&gt;#nested-span&lt;/feature&gt;
-&lt;feature value="optional"&gt;#opacity&lt;/feature&gt;
-&lt;feature value="optional"&gt;#origin&lt;/feature&gt;
-&lt;feature value="optional"&gt;#overflow-scroll&lt;/feature&gt;
-&lt;feature value="optional"&gt;#overflow-visible&lt;/feature&gt;
-&lt;feature value="optional"&gt;#overflow&lt;/feature&gt;
-&lt;feature value="optional"&gt;#padding-1&lt;/feature&gt;
-&lt;feature value="optional"&gt;#padding-2&lt;/feature&gt;
-&lt;feature value="optional"&gt;#padding-3&lt;/feature&gt;
-&lt;feature value="optional"&gt;#padding-4&lt;/feature&gt;
-&lt;feature value="optional"&gt;#padding&lt;/feature&gt;
-&lt;feature value="optional"&gt;#pixelAspectRatio&lt;/feature&gt;
-&lt;feature value="optional"&gt;#presentation&lt;/feature&gt;
-&lt;feature value="optional"&gt;#rollUp&lt;/feature&gt;
-&lt;feature value="optional"&gt;#showBackground&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-chained&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-inheritance-content&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-inheritance-region&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-inline&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-nested&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-referential&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling&lt;/feature&gt;
-&lt;feature value="optional"&gt;#subFrameRate&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textAlign-absolute&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textAlign-relative&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textAlign&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textDecoration-over&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textDecoration-through&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textDecoration-under&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textDecoration&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textOutline-blurred&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textOutline-unblurred&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textOutline&lt;/feature&gt;
-&lt;feature value="optional"&gt;#tickRate&lt;/feature&gt;
-&lt;feature value="optional"&gt;#time-clock-with-frames&lt;/feature&gt;
-&lt;feature value="optional"&gt;#time-clock&lt;/feature&gt;
-&lt;feature value="optional"&gt;#time-offset-with-frames&lt;/feature&gt;
-&lt;feature value="optional"&gt;#time-offset-with-ticks&lt;/feature&gt;
-&lt;feature value="optional"&gt;#timeBase-clock&lt;/feature&gt;
-&lt;feature value="optional"&gt;#timeBase-media&lt;/feature&gt;
-&lt;feature value="optional"&gt;#timeBase-smpte&lt;/feature&gt;
-&lt;feature value="optional"&gt;#timeContainer&lt;/feature&gt;
-&lt;feature value="optional"&gt;#unicodeBidi&lt;/feature&gt;
-&lt;feature value="optional"&gt;#visibility-block&lt;/feature&gt;
-&lt;feature value="optional"&gt;#visibility-inline&lt;/feature&gt;
-&lt;feature value="optional"&gt;#visibility-region&lt;/feature&gt;
-&lt;feature value="optional"&gt;#visibility&lt;/feature&gt;
-&lt;feature value="optional"&gt;#wrapOption&lt;/feature&gt;
-&lt;feature value="optional"&gt;#writingMode-horizontal-lr&lt;/feature&gt;
-&lt;feature value="optional"&gt;#writingMode-horizontal-rl&lt;/feature&gt;
-&lt;feature value="optional"&gt;#writingMode-horizontal&lt;/feature&gt;
-&lt;feature value="optional"&gt;#writingMode-vertical&lt;/feature&gt;
-&lt;feature value="optional"&gt;#writingMode&lt;/feature&gt;
-&lt;feature value="optional"&gt;#zIndex&lt;/feature&gt;
-&lt;/features&gt;
-&lt;extensions xml:base="http://www.w3.org/ns/ttml/extension/"&gt;
-&lt;!-- required (mandatory) extension support --&gt;
-&lt;!-- optional (voluntary) extension support --&gt;
-&lt;/extensions&gt;
+  &lt;features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
+    &lt;!-- required (mandatory) feature support --&gt;
+    &lt;feature value="required"&gt;#content&lt;/feature&gt;
+    &lt;feature value="required"&gt;#core&lt;/feature&gt;
+    &lt;feature value="required"&gt;#profile&lt;/feature&gt;
+    &lt;feature value="required"&gt;#structure&lt;/feature&gt;
+    &lt;feature value="required"&gt;#time-offset&lt;/feature&gt;
+    &lt;feature value="required"&gt;#timing&lt;/feature&gt;
+    &lt;feature value="required"&gt;#transformation&lt;/feature&gt;
+    &lt;!-- optional (voluntary) feature support --&gt;
+    &lt;feature value="optional"&gt;#animation&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#backgroundColor-block&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#backgroundColor-inline&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#backgroundColor-region&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#backgroundColor&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#bidi&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#cellResolution&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#clockMode-gps&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#clockMode-local&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#clockMode-utc&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#clockMode&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#color&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#direction&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#display-block&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#display-inline&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#display-region&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#display&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#displayAlign&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#dropMode-dropNTSC&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#dropMode-dropPAL&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#dropMode-nonDrop&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#dropMode&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#extent-region&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#extent-root&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#extent&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontFamily-generic&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontFamily-non-generic&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontFamily&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontSize-anamorphic&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontSize-isomorphic&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontSize&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontStyle-italic&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontStyle-oblique&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontStyle-reverseOblique&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontStyle&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontWeight-bold&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontWeight&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#frameRate&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#frameRateMultiplier&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#layout&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-cell&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-em&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-negative&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-percentage&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-pixel&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-positive&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-real&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#lineBreak-uax14&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#lineHeight&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#markerMode-continuous&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#markerMode-discontinuous&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#markerMode&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#metadata-foreign&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#metadata&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#nested-div&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#nested-span&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#opacity&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#origin&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#overflow-scroll&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#overflow-visible&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#overflow&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#padding-1&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#padding-2&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#padding-3&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#padding-4&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#padding&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#pixelAspectRatio&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#presentation&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#showBackground&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-chained&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-inheritance-content&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-inheritance-region&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-inline&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-nested&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-referential&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#subFrameRate&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textAlign-absolute&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textAlign-relative&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textAlign&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textDecoration-over&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textDecoration-through&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textDecoration-under&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textDecoration&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textOutline-blurred&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textOutline-unblurred&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textOutline&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#tickRate&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#time-clock-with-frames&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#time-clock&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#time-offset-with-frames&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#time-offset-with-ticks&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#timeBase-clock&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#timeBase-media&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#timeBase-smpte&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#timeContainer&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#unicodeBidi&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#visibility-block&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#visibility-inline&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#visibility-region&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#visibility&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#wrapOption&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#writingMode-horizontal-lr&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#writingMode-horizontal-rl&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#writingMode-horizontal&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#writingMode-vertical&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#writingMode&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#zIndex&lt;/feature&gt;
+  &lt;/features&gt;
+  &lt;extensions xml:base="http://www.w3.org/ns/ttml/extension/"&gt;
+    &lt;!-- required (mandatory) extension support --&gt;
+    &lt;!-- optional (voluntary) extension support --&gt;
+  &lt;/extensions&gt;
 &lt;/profile&gt;
+
 </pre></div></div><div class="div2">
 <h3><a name="profile-dfxp-presentation" id="profile-dfxp-presentation"/>F.2 DFXP Presentation Profile</h3><p>The DFXP Presentation Profile is intended to be used to
 express minimum compliance for presentation processing.</p><div class="exampleInner"><pre>&lt;?xml version="1.0" encoding="utf-8"?&gt;
 &lt;!-- this file defines the "dfxp-presentation" profile of ttaf1-dfxp --&gt;
 &lt;profile xmlns="http://www.w3.org/ns/ttml#parameter"&gt;
-&lt;features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
-&lt;!-- required (mandatory) feature support --&gt;
-&lt;feature value="required"&gt;#content&lt;/feature&gt;
-&lt;feature value="required"&gt;#core&lt;/feature&gt;
-&lt;feature value="required"&gt;#presentation&lt;/feature&gt;
-&lt;feature value="required"&gt;#profile&lt;/feature&gt;
-&lt;feature value="required"&gt;#structure&lt;/feature&gt;
-&lt;feature value="required"&gt;#time-offset&lt;/feature&gt;
-&lt;feature value="required"&gt;#timing&lt;/feature&gt;
-&lt;!-- optional (voluntary) feature support --&gt;
-&lt;feature value="optional"&gt;#animation&lt;/feature&gt;
-&lt;feature value="optional"&gt;#backgroundColor-block&lt;/feature&gt;
-&lt;feature value="optional"&gt;#backgroundColor-inline&lt;/feature&gt;
-&lt;feature value="optional"&gt;#backgroundColor-region&lt;/feature&gt;
-&lt;feature value="optional"&gt;#backgroundColor&lt;/feature&gt;
-&lt;feature value="optional"&gt;#bidi&lt;/feature&gt;
-&lt;feature value="optional"&gt;#cellResolution&lt;/feature&gt;
-&lt;feature value="optional"&gt;#clockMode-gps&lt;/feature&gt;
-&lt;feature value="optional"&gt;#clockMode-local&lt;/feature&gt;
-&lt;feature value="optional"&gt;#clockMode-utc&lt;/feature&gt;
-&lt;feature value="optional"&gt;#clockMode&lt;/feature&gt;
-&lt;feature value="optional"&gt;#color&lt;/feature&gt;
-&lt;feature value="optional"&gt;#direction&lt;/feature&gt;
-&lt;feature value="optional"&gt;#display-block&lt;/feature&gt;
-&lt;feature value="optional"&gt;#display-inline&lt;/feature&gt;
-&lt;feature value="optional"&gt;#display-region&lt;/feature&gt;
-&lt;feature value="optional"&gt;#display&lt;/feature&gt;
-&lt;feature value="optional"&gt;#displayAlign&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dropMode-dropNTSC&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dropMode-dropPAL&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dropMode-nonDrop&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dropMode&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-character&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-clear&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-fill&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-glyph&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-in&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-jump&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-line&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-out&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-rollUp&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-smooth&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-teletext&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow-word&lt;/feature&gt;
-&lt;feature value="optional"&gt;#dynamicFlow&lt;/feature&gt;
-&lt;feature value="optional"&gt;#extent-region&lt;/feature&gt;
-&lt;feature value="optional"&gt;#extent-root&lt;/feature&gt;
-&lt;feature value="optional"&gt;#extent&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontFamily-generic&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontFamily-non-generic&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontFamily&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontSize-anamorphic&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontSize-isomorphic&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontSize&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontStyle-italic&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontStyle-oblique&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontStyle-reverseOblique&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontStyle&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontWeight-bold&lt;/feature&gt;
-&lt;feature value="optional"&gt;#fontWeight&lt;/feature&gt;
-&lt;feature value="optional"&gt;#frameRate&lt;/feature&gt;
-&lt;feature value="optional"&gt;#frameRateMultiplier&lt;/feature&gt;
-&lt;feature value="optional"&gt;#layout&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-cell&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-em&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-negative&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-percentage&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-pixel&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-positive&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length-real&lt;/feature&gt;
-&lt;feature value="optional"&gt;#length&lt;/feature&gt;
-&lt;feature value="optional"&gt;#lineBreak-uax14&lt;/feature&gt;
-&lt;feature value="optional"&gt;#lineHeight&lt;/feature&gt;
-&lt;feature value="optional"&gt;#markerMode-continuous&lt;/feature&gt;
-&lt;feature value="optional"&gt;#markerMode-discontinuous&lt;/feature&gt;
-&lt;feature value="optional"&gt;#markerMode&lt;/feature&gt;
-&lt;feature value="optional"&gt;#metadata-foreign&lt;/feature&gt;
-&lt;feature value="optional"&gt;#metadata&lt;/feature&gt;
-&lt;feature value="optional"&gt;#nested-div&lt;/feature&gt;
-&lt;feature value="optional"&gt;#nested-span&lt;/feature&gt;
-&lt;feature value="optional"&gt;#opacity&lt;/feature&gt;
-&lt;feature value="optional"&gt;#origin&lt;/feature&gt;
-&lt;feature value="optional"&gt;#overflow-scroll&lt;/feature&gt;
-&lt;feature value="optional"&gt;#overflow-visible&lt;/feature&gt;
-&lt;feature value="optional"&gt;#overflow&lt;/feature&gt;
-&lt;feature value="optional"&gt;#padding-1&lt;/feature&gt;
-&lt;feature value="optional"&gt;#padding-2&lt;/feature&gt;
-&lt;feature value="optional"&gt;#padding-3&lt;/feature&gt;
-&lt;feature value="optional"&gt;#padding-4&lt;/feature&gt;
-&lt;feature value="optional"&gt;#padding&lt;/feature&gt;
-&lt;feature value="optional"&gt;#pixelAspectRatio&lt;/feature&gt;
-&lt;feature value="optional"&gt;#rollUp&lt;/feature&gt;
-&lt;feature value="optional"&gt;#showBackground&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-chained&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-inheritance-content&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-inheritance-region&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-inline&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-nested&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling-referential&lt;/feature&gt;
-&lt;feature value="optional"&gt;#styling&lt;/feature&gt;
-&lt;feature value="optional"&gt;#subFrameRate&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textAlign-absolute&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textAlign-relative&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textAlign&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textDecoration-over&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textDecoration-through&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textDecoration-under&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textDecoration&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textOutline-blurred&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textOutline-unblurred&lt;/feature&gt;
-&lt;feature value="optional"&gt;#textOutline&lt;/feature&gt;
-&lt;feature value="optional"&gt;#tickRate&lt;/feature&gt;
-&lt;feature value="optional"&gt;#time-clock-with-frames&lt;/feature&gt;
-&lt;feature value="optional"&gt;#time-clock&lt;/feature&gt;
-&lt;feature value="optional"&gt;#time-offset-with-frames&lt;/feature&gt;
-&lt;feature value="optional"&gt;#time-offset-with-ticks&lt;/feature&gt;
-&lt;feature value="optional"&gt;#timeBase-clock&lt;/feature&gt;
-&lt;feature value="optional"&gt;#timeBase-media&lt;/feature&gt;
-&lt;feature value="optional"&gt;#timeBase-smpte&lt;/feature&gt;
-&lt;feature value="optional"&gt;#timeContainer&lt;/feature&gt;
-&lt;feature value="optional"&gt;#transformation&lt;/feature&gt;
-&lt;feature value="optional"&gt;#unicodeBidi&lt;/feature&gt;
-&lt;feature value="optional"&gt;#visibility-block&lt;/feature&gt;
-&lt;feature value="optional"&gt;#visibility-inline&lt;/feature&gt;
-&lt;feature value="optional"&gt;#visibility-region&lt;/feature&gt;
-&lt;feature value="optional"&gt;#visibility&lt;/feature&gt;
-&lt;feature value="optional"&gt;#wrapOption&lt;/feature&gt;
-&lt;feature value="optional"&gt;#writingMode-horizontal-lr&lt;/feature&gt;
-&lt;feature value="optional"&gt;#writingMode-horizontal-rl&lt;/feature&gt;
-&lt;feature value="optional"&gt;#writingMode-horizontal&lt;/feature&gt;
-&lt;feature value="optional"&gt;#writingMode-vertical&lt;/feature&gt;
-&lt;feature value="optional"&gt;#writingMode&lt;/feature&gt;
-&lt;feature value="optional"&gt;#zIndex&lt;/feature&gt;
-&lt;/features&gt;
-&lt;extensions xml:base="http://www.w3.org/ns/ttml/extension/"&gt;
-&lt;!-- required (mandatory) extension support --&gt;
-&lt;!-- optional (voluntary) extension support --&gt;
-&lt;/extensions&gt;
+  &lt;features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
+    &lt;!-- required (mandatory) feature support --&gt;
+    &lt;feature value="required"&gt;#content&lt;/feature&gt;
+    &lt;feature value="required"&gt;#core&lt;/feature&gt;
+    &lt;feature value="required"&gt;#presentation&lt;/feature&gt;
+    &lt;feature value="required"&gt;#profile&lt;/feature&gt;
+    &lt;feature value="required"&gt;#structure&lt;/feature&gt;
+    &lt;feature value="required"&gt;#time-offset&lt;/feature&gt;
+    &lt;feature value="required"&gt;#timing&lt;/feature&gt;
+    &lt;!-- optional (voluntary) feature support --&gt;
+    &lt;feature value="optional"&gt;#animation&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#backgroundColor-block&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#backgroundColor-inline&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#backgroundColor-region&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#backgroundColor&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#bidi&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#cellResolution&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#clockMode-gps&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#clockMode-local&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#clockMode-utc&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#clockMode&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#color&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#direction&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#display-block&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#display-inline&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#display-region&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#display&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#displayAlign&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#dropMode-dropNTSC&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#dropMode-dropPAL&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#dropMode-nonDrop&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#dropMode&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#extent-region&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#extent-root&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#extent&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontFamily-generic&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontFamily-non-generic&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontFamily&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontSize-anamorphic&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontSize-isomorphic&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontSize&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontStyle-italic&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontStyle-oblique&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontStyle-reverseOblique&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontStyle&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontWeight-bold&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#fontWeight&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#frameRate&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#frameRateMultiplier&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#layout&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-cell&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-em&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-negative&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-percentage&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-pixel&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-positive&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length-real&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#length&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#lineBreak-uax14&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#lineHeight&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#markerMode-continuous&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#markerMode-discontinuous&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#markerMode&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#metadata-foreign&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#metadata&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#nested-div&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#nested-span&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#opacity&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#origin&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#overflow-scroll&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#overflow-visible&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#overflow&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#padding-1&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#padding-2&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#padding-3&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#padding-4&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#padding&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#pixelAspectRatio&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#showBackground&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-chained&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-inheritance-content&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-inheritance-region&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-inline&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-nested&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling-referential&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#styling&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#subFrameRate&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textAlign-absolute&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textAlign-relative&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textAlign&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textDecoration-over&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textDecoration-through&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textDecoration-under&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textDecoration&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textOutline-blurred&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textOutline-unblurred&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#textOutline&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#tickRate&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#time-clock-with-frames&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#time-clock&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#time-offset-with-frames&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#time-offset-with-ticks&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#timeBase-clock&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#timeBase-media&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#timeBase-smpte&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#timeContainer&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#transformation&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#unicodeBidi&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#visibility-block&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#visibility-inline&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#visibility-region&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#visibility&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#wrapOption&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#writingMode-horizontal-lr&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#writingMode-horizontal-rl&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#writingMode-horizontal&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#writingMode-vertical&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#writingMode&lt;/feature&gt;
+    &lt;feature value="optional"&gt;#zIndex&lt;/feature&gt;
+  &lt;/features&gt;
+  &lt;extensions xml:base="http://www.w3.org/ns/ttml/extension/"&gt;
+    &lt;!-- required (mandatory) extension support --&gt;
+    &lt;!-- optional (voluntary) extension support --&gt;
+  &lt;/extensions&gt;
 &lt;/profile&gt;
+
 </pre></div></div><div class="div2">
 <h3><a name="profile-dfxp-full" id="profile-dfxp-full"/>F.3 DFXP Full Profile</h3><p>The DFXP Full Profile is intended to be used to
 express maximum compliance for both transformation and presentation processing.</p><div class="exampleInner"><pre>&lt;?xml version="1.0" encoding="utf-8"?&gt;
 &lt;!-- this file defines the "dfxp-full" profile of ttaf1-dfxp --&gt;
 &lt;profile xmlns="http://www.w3.org/ns/ttml#parameter"&gt;
-&lt;features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
-&lt;!-- required (mandatory) feature support --&gt;
-&lt;feature value="required"&gt;#animation&lt;/feature&gt;
-&lt;feature value="required"&gt;#backgroundColor-block&lt;/feature&gt;
-&lt;feature value="required"&gt;#backgroundColor-inline&lt;/feature&gt;
-&lt;feature value="required"&gt;#backgroundColor-region&lt;/feature&gt;
-&lt;feature value="required"&gt;#backgroundColor&lt;/feature&gt;
-&lt;feature value="required"&gt;#bidi&lt;/feature&gt;
-&lt;feature value="required"&gt;#cellResolution&lt;/feature&gt;
-&lt;feature value="required"&gt;#clockMode-gps&lt;/feature&gt;
-&lt;feature value="required"&gt;#clockMode-local&lt;/feature&gt;
-&lt;feature value="required"&gt;#clockMode-utc&lt;/feature&gt;
-&lt;feature value="required"&gt;#clockMode&lt;/feature&gt;
-&lt;feature value="required"&gt;#color&lt;/feature&gt;
-&lt;feature value="required"&gt;#content&lt;/feature&gt;
-&lt;feature value="required"&gt;#core&lt;/feature&gt;
-&lt;feature value="required"&gt;#direction&lt;/feature&gt;
-&lt;feature value="required"&gt;#display-block&lt;/feature&gt;
-&lt;feature value="required"&gt;#display-inline&lt;/feature&gt;
-&lt;feature value="required"&gt;#display-region&lt;/feature&gt;
-&lt;feature value="required"&gt;#display&lt;/feature&gt;
-&lt;feature value="required"&gt;#displayAlign&lt;/feature&gt;
-&lt;feature value="required"&gt;#dropMode-dropNTSC&lt;/feature&gt;
-&lt;feature value="required"&gt;#dropMode-dropPAL&lt;/feature&gt;
-&lt;feature value="required"&gt;#dropMode-nonDrop&lt;/feature&gt;
-&lt;feature value="required"&gt;#dropMode&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-character&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-clear&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-fill&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-glyph&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-in&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-jump&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-line&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-out&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-rollUp&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-smooth&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-teletext&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow-word&lt;/feature&gt;
-&lt;feature value="required"&gt;#dynamicFlow&lt;/feature&gt;
-&lt;feature value="required"&gt;#extent-region&lt;/feature&gt;
-&lt;feature value="required"&gt;#extent-root&lt;/feature&gt;
-&lt;feature value="required"&gt;#extent&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontFamily-generic&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontFamily-non-generic&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontFamily&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontSize-anamorphic&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontSize-isomorphic&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontSize&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontStyle-italic&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontStyle-oblique&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontStyle-reverseOblique&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontStyle&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontWeight-bold&lt;/feature&gt;
-&lt;feature value="required"&gt;#fontWeight&lt;/feature&gt;
-&lt;feature value="required"&gt;#frameRate&lt;/feature&gt;
-&lt;feature value="required"&gt;#frameRateMultiplier&lt;/feature&gt;
-&lt;feature value="required"&gt;#layout&lt;/feature&gt;
-&lt;feature value="required"&gt;#length-cell&lt;/feature&gt;
-&lt;feature value="required"&gt;#length-em&lt;/feature&gt;
-&lt;feature value="required"&gt;#length-negative&lt;/feature&gt;
-&lt;feature value="required"&gt;#length-percentage&lt;/feature&gt;
-&lt;feature value="required"&gt;#length-pixel&lt;/feature&gt;
-&lt;feature value="required"&gt;#length-positive&lt;/feature&gt;
-&lt;feature value="required"&gt;#length-real&lt;/feature&gt;
-&lt;feature value="required"&gt;#length&lt;/feature&gt;
-&lt;feature value="required"&gt;#lineBreak-uax14&lt;/feature&gt;
-&lt;feature value="required"&gt;#lineHeight&lt;/feature&gt;
-&lt;feature value="required"&gt;#markerMode-continuous&lt;/feature&gt;
-&lt;feature value="required"&gt;#markerMode-discontinuous&lt;/feature&gt;
-&lt;feature value="required"&gt;#markerMode&lt;/feature&gt;
-&lt;feature value="required"&gt;#metadata-foreign&lt;/feature&gt;
-&lt;feature value="required"&gt;#metadata&lt;/feature&gt;
-&lt;feature value="required"&gt;#nested-div&lt;/feature&gt;
-&lt;feature value="required"&gt;#nested-span&lt;/feature&gt;
-&lt;feature value="required"&gt;#opacity&lt;/feature&gt;
-&lt;feature value="required"&gt;#origin&lt;/feature&gt;
-&lt;feature value="required"&gt;#overflow-scroll&lt;/feature&gt;
-&lt;feature value="required"&gt;#overflow-visible&lt;/feature&gt;
-&lt;feature value="required"&gt;#overflow&lt;/feature&gt;
-&lt;feature value="required"&gt;#padding-1&lt;/feature&gt;
-&lt;feature value="required"&gt;#padding-2&lt;/feature&gt;
-&lt;feature value="required"&gt;#padding-3&lt;/feature&gt;
-&lt;feature value="required"&gt;#padding-4&lt;/feature&gt;
-&lt;feature value="required"&gt;#padding&lt;/feature&gt;
-&lt;feature value="required"&gt;#pixelAspectRatio&lt;/feature&gt;
-&lt;feature value="required"&gt;#presentation&lt;/feature&gt;
-&lt;feature value="required"&gt;#profile&lt;/feature&gt;
-&lt;feature value="required"&gt;#rollUp&lt;/feature&gt;
-&lt;feature value="required"&gt;#showBackground&lt;/feature&gt;
-&lt;feature value="required"&gt;#structure&lt;/feature&gt;
-&lt;feature value="required"&gt;#styling-chained&lt;/feature&gt;
-&lt;feature value="required"&gt;#styling-inheritance-content&lt;/feature&gt;
-&lt;feature value="required"&gt;#styling-inheritance-region&lt;/feature&gt;
-&lt;feature value="required"&gt;#styling-inline&lt;/feature&gt;
-&lt;feature value="required"&gt;#styling-nested&lt;/feature&gt;
-&lt;feature value="required"&gt;#styling-referential&lt;/feature&gt;
-&lt;feature value="required"&gt;#styling&lt;/feature&gt;
-&lt;feature value="required"&gt;#subFrameRate&lt;/feature&gt;
-&lt;feature value="required"&gt;#textAlign-absolute&lt;/feature&gt;
-&lt;feature value="required"&gt;#textAlign-relative&lt;/feature&gt;
-&lt;feature value="required"&gt;#textAlign&lt;/feature&gt;
-&lt;feature value="required"&gt;#textDecoration-over&lt;/feature&gt;
-&lt;feature value="required"&gt;#textDecoration-through&lt;/feature&gt;
-&lt;feature value="required"&gt;#textDecoration-under&lt;/feature&gt;
-&lt;feature value="required"&gt;#textDecoration&lt;/feature&gt;
-&lt;feature value="required"&gt;#textOutline-blurred&lt;/feature&gt;
-&lt;feature value="required"&gt;#textOutline-unblurred&lt;/feature&gt;
-&lt;feature value="required"&gt;#textOutline&lt;/feature&gt;
-&lt;feature value="required"&gt;#tickRate&lt;/feature&gt;
-&lt;feature value="required"&gt;#time-clock-with-frames&lt;/feature&gt;
-&lt;feature value="required"&gt;#time-clock&lt;/feature&gt;
-&lt;feature value="required"&gt;#time-offset-with-frames&lt;/feature&gt;
-&lt;feature value="required"&gt;#time-offset-with-ticks&lt;/feature&gt;
-&lt;feature value="required"&gt;#time-offset&lt;/feature&gt;
-&lt;feature value="required"&gt;#timeBase-clock&lt;/feature&gt;
-&lt;feature value="required"&gt;#timeBase-media&lt;/feature&gt;
-&lt;feature value="required"&gt;#timeBase-smpte&lt;/feature&gt;
-&lt;feature value="required"&gt;#timeContainer&lt;/feature&gt;
-&lt;feature value="required"&gt;#timing&lt;/feature&gt;
-&lt;feature value="required"&gt;#transformation&lt;/feature&gt;
-&lt;feature value="required"&gt;#unicodeBidi&lt;/feature&gt;
-&lt;feature value="required"&gt;#visibility-block&lt;/feature&gt;
-&lt;feature value="required"&gt;#visibility-inline&lt;/feature&gt;
-&lt;feature value="required"&gt;#visibility-region&lt;/feature&gt;
-&lt;feature value="required"&gt;#visibility&lt;/feature&gt;
-&lt;feature value="required"&gt;#wrapOption&lt;/feature&gt;
-&lt;feature value="required"&gt;#writingMode-horizontal-lr&lt;/feature&gt;
-&lt;feature value="required"&gt;#writingMode-horizontal-rl&lt;/feature&gt;
-&lt;feature value="required"&gt;#writingMode-horizontal&lt;/feature&gt;
-&lt;feature value="required"&gt;#writingMode-vertical&lt;/feature&gt;
-&lt;feature value="required"&gt;#writingMode&lt;/feature&gt;
-&lt;feature value="required"&gt;#zIndex&lt;/feature&gt;
-&lt;!-- optional (voluntary) feature support --&gt;
-&lt;/features&gt;
-&lt;extensions xml:base="http://www.w3.org/ns/ttml/extension/"&gt;
-&lt;!-- required (mandatory) extension support --&gt;
-&lt;!-- optional (voluntary) extension support --&gt;
-&lt;/extensions&gt;
+  &lt;features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
+    &lt;!-- required (mandatory) feature support --&gt;
+    &lt;feature value="required"&gt;#animation&lt;/feature&gt;
+    &lt;feature value="required"&gt;#backgroundColor-block&lt;/feature&gt;
+    &lt;feature value="required"&gt;#backgroundColor-inline&lt;/feature&gt;
+    &lt;feature value="required"&gt;#backgroundColor-region&lt;/feature&gt;
+    &lt;feature value="required"&gt;#backgroundColor&lt;/feature&gt;
+    &lt;feature value="required"&gt;#bidi&lt;/feature&gt;
+    &lt;feature value="required"&gt;#cellResolution&lt;/feature&gt;
+    &lt;feature value="required"&gt;#clockMode-gps&lt;/feature&gt;
+    &lt;feature value="required"&gt;#clockMode-local&lt;/feature&gt;
+    &lt;feature value="required"&gt;#clockMode-utc&lt;/feature&gt;
+    &lt;feature value="required"&gt;#clockMode&lt;/feature&gt;
+    &lt;feature value="required"&gt;#color&lt;/feature&gt;
+    &lt;feature value="required"&gt;#content&lt;/feature&gt;
+    &lt;feature value="required"&gt;#core&lt;/feature&gt;
+    &lt;feature value="required"&gt;#direction&lt;/feature&gt;
+    &lt;feature value="required"&gt;#display-block&lt;/feature&gt;
+    &lt;feature value="required"&gt;#display-inline&lt;/feature&gt;
+    &lt;feature value="required"&gt;#display-region&lt;/feature&gt;
+    &lt;feature value="required"&gt;#display&lt;/feature&gt;
+    &lt;feature value="required"&gt;#displayAlign&lt;/feature&gt;
+    &lt;feature value="required"&gt;#dropMode-dropNTSC&lt;/feature&gt;
+    &lt;feature value="required"&gt;#dropMode-dropPAL&lt;/feature&gt;
+    &lt;feature value="required"&gt;#dropMode-nonDrop&lt;/feature&gt;
+    &lt;feature value="required"&gt;#dropMode&lt;/feature&gt;
+    &lt;feature value="required"&gt;#extent-region&lt;/feature&gt;
+    &lt;feature value="required"&gt;#extent-root&lt;/feature&gt;
+    &lt;feature value="required"&gt;#extent&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontFamily-generic&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontFamily-non-generic&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontFamily&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontSize-anamorphic&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontSize-isomorphic&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontSize&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontStyle-italic&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontStyle-oblique&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontStyle-reverseOblique&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontStyle&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontWeight-bold&lt;/feature&gt;
+    &lt;feature value="required"&gt;#fontWeight&lt;/feature&gt;
+    &lt;feature value="required"&gt;#frameRate&lt;/feature&gt;
+    &lt;feature value="required"&gt;#frameRateMultiplier&lt;/feature&gt;
+    &lt;feature value="required"&gt;#layout&lt;/feature&gt;
+    &lt;feature value="required"&gt;#length-cell&lt;/feature&gt;
+    &lt;feature value="required"&gt;#length-em&lt;/feature&gt;
+    &lt;feature value="required"&gt;#length-negative&lt;/feature&gt;
+    &lt;feature value="required"&gt;#length-percentage&lt;/feature&gt;
+    &lt;feature value="required"&gt;#length-pixel&lt;/feature&gt;
+    &lt;feature value="required"&gt;#length-positive&lt;/feature&gt;
+    &lt;feature value="required"&gt;#length-real&lt;/feature&gt;
+    &lt;feature value="required"&gt;#length&lt;/feature&gt;
+    &lt;feature value="required"&gt;#lineBreak-uax14&lt;/feature&gt;
+    &lt;feature value="required"&gt;#lineHeight&lt;/feature&gt;
+    &lt;feature value="required"&gt;#markerMode-continuous&lt;/feature&gt;
+    &lt;feature value="required"&gt;#markerMode-discontinuous&lt;/feature&gt;
+    &lt;feature value="required"&gt;#markerMode&lt;/feature&gt;
+    &lt;feature value="required"&gt;#metadata-foreign&lt;/feature&gt;
+    &lt;feature value="required"&gt;#metadata&lt;/feature&gt;
+    &lt;feature value="required"&gt;#nested-div&lt;/feature&gt;
+    &lt;feature value="required"&gt;#nested-span&lt;/feature&gt;
+    &lt;feature value="required"&gt;#opacity&lt;/feature&gt;
+    &lt;feature value="required"&gt;#origin&lt;/feature&gt;
+    &lt;feature value="required"&gt;#overflow-scroll&lt;/feature&gt;
+    &lt;feature value="required"&gt;#overflow-visible&lt;/feature&gt;
+    &lt;feature value="required"&gt;#overflow&lt;/feature&gt;
+    &lt;feature value="required"&gt;#padding-1&lt;/feature&gt;
+    &lt;feature value="required"&gt;#padding-2&lt;/feature&gt;
+    &lt;feature value="required"&gt;#padding-3&lt;/feature&gt;
+    &lt;feature value="required"&gt;#padding-4&lt;/feature&gt;
+    &lt;feature value="required"&gt;#padding&lt;/feature&gt;
+    &lt;feature value="required"&gt;#pixelAspectRatio&lt;/feature&gt;
+    &lt;feature value="required"&gt;#presentation&lt;/feature&gt;
+    &lt;feature value="required"&gt;#profile&lt;/feature&gt;
+    &lt;feature value="required"&gt;#showBackground&lt;/feature&gt;
+    &lt;feature value="required"&gt;#structure&lt;/feature&gt;
+    &lt;feature value="required"&gt;#styling-chained&lt;/feature&gt;
+    &lt;feature value="required"&gt;#styling-inheritance-content&lt;/feature&gt;
+    &lt;feature value="required"&gt;#styling-inheritance-region&lt;/feature&gt;
+    &lt;feature value="required"&gt;#styling-inline&lt;/feature&gt;
+    &lt;feature value="required"&gt;#styling-nested&lt;/feature&gt;
+    &lt;feature value="required"&gt;#styling-referential&lt;/feature&gt;
+    &lt;feature value="required"&gt;#styling&lt;/feature&gt;
+    &lt;feature value="required"&gt;#subFrameRate&lt;/feature&gt;
+    &lt;feature value="required"&gt;#textAlign-absolute&lt;/feature&gt;
+    &lt;feature value="required"&gt;#textAlign-relative&lt;/feature&gt;
+    &lt;feature value="required"&gt;#textAlign&lt;/feature&gt;
+    &lt;feature value="required"&gt;#textDecoration-over&lt;/feature&gt;
+    &lt;feature value="required"&gt;#textDecoration-through&lt;/feature&gt;
+    &lt;feature value="required"&gt;#textDecoration-under&lt;/feature&gt;
+    &lt;feature value="required"&gt;#textDecoration&lt;/feature&gt;
+    &lt;feature value="required"&gt;#textOutline-blurred&lt;/feature&gt;
+    &lt;feature value="required"&gt;#textOutline-unblurred&lt;/feature&gt;
+    &lt;feature value="required"&gt;#textOutline&lt;/feature&gt;
+    &lt;feature value="required"&gt;#tickRate&lt;/feature&gt;
+    &lt;feature value="required"&gt;#time-clock-with-frames&lt;/feature&gt;
+    &lt;feature value="required"&gt;#time-clock&lt;/feature&gt;
+    &lt;feature value="required"&gt;#time-offset-with-frames&lt;/feature&gt;
+    &lt;feature value="required"&gt;#time-offset-with-ticks&lt;/feature&gt;
+    &lt;feature value="required"&gt;#time-offset&lt;/feature&gt;
+    &lt;feature value="required"&gt;#timeBase-clock&lt;/feature&gt;
+    &lt;feature value="required"&gt;#timeBase-media&lt;/feature&gt;
+    &lt;feature value="required"&gt;#timeBase-smpte&lt;/feature&gt;
+    &lt;feature value="required"&gt;#timeContainer&lt;/feature&gt;
+    &lt;feature value="required"&gt;#timing&lt;/feature&gt;
+    &lt;feature value="required"&gt;#transformation&lt;/feature&gt;
+    &lt;feature value="required"&gt;#unicodeBidi&lt;/feature&gt;
+    &lt;feature value="required"&gt;#visibility-block&lt;/feature&gt;
+    &lt;feature value="required"&gt;#visibility-inline&lt;/feature&gt;
+    &lt;feature value="required"&gt;#visibility-region&lt;/feature&gt;
+    &lt;feature value="required"&gt;#visibility&lt;/feature&gt;
+    &lt;feature value="required"&gt;#wrapOption&lt;/feature&gt;
+    &lt;feature value="required"&gt;#writingMode-horizontal-lr&lt;/feature&gt;
+    &lt;feature value="required"&gt;#writingMode-horizontal-rl&lt;/feature&gt;
+    &lt;feature value="required"&gt;#writingMode-horizontal&lt;/feature&gt;
+    &lt;feature value="required"&gt;#writingMode-vertical&lt;/feature&gt;
+    &lt;feature value="required"&gt;#writingMode&lt;/feature&gt;
+    &lt;feature value="required"&gt;#zIndex&lt;/feature&gt;
+    &lt;!-- optional (voluntary) feature support --&gt;
+  &lt;/features&gt;
+  &lt;extensions xml:base="http://www.w3.org/ns/ttml/extension/"&gt;
+    &lt;!-- required (mandatory) extension support --&gt;
+    &lt;!-- optional (voluntary) extension support --&gt;
+  &lt;/extensions&gt;
 &lt;/profile&gt;
+
 </pre></div></div></div><div class="div1">
 <h2><a name="references" id="references"/>G References</h2><p><em>This appendix is normative.</em></p><dl><dt class="label"><a name="css2" id="css2"/>CSS2</dt><dd>Bert Bos et al.,
 <a href="http://www.w3.org/TR/1998/REC-CSS2-19980512/"><cite>Cascading
@@ -8379,7 +8331,7 @@
 <h2><a name="derivation" id="derivation"/>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 name="d3e17024" id="d3e17024"/>J.1 Element Derivation</h3><p>The first column of <a href="#element-vocab-derivation-table"><b>Table K-1 – Elements</b></a>
+<h3><a name="d3e17015" id="d3e17015"/>J.1 Element Derivation</h3><p>The first column of <a href="#element-vocab-derivation-table"><b>Table K-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
@@ -8434,7 +8386,7 @@
 and <code>@requiredFeatures</code> on the <code>svg:svg</code> element,
 but extended to support distinct specification of optionality.</p></li><li><p>Derived from the use of <code>@baseProfile</code>
 and <code>@version</code> on the <code>svg:svg</code> element.</p></li></ol></div></div><div class="div2">
-<h3><a name="d3e17503" id="d3e17503"/>J.2 Attribute Derivation</h3><p>The first column of <a href="#attribute-vocab-derivation-table"><b>Table K-2 – Attributes</b></a>
+<h3><a name="d3e17494" id="d3e17494"/>J.2 Attribute Derivation</h3><p>The first column of <a href="#attribute-vocab-derivation-table"><b>Table K-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
@@ -8506,9 +8458,9 @@
 <h2><a name="qa" id="qa"/>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> <a href="#qaf-sg">[QAF SG]</a>.</p><div class="div2">
-<h3><a name="d3e18391" id="d3e18391"/>K.1 Requirements</h3><table summary="HTML Table" id="qa-framework-requirements-table" class="common"><caption>Table L-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 name="d3e18382" id="d3e18382"/>K.1 Requirements</h3><table summary="HTML Table" id="qa-framework-requirements-table" class="common"><caption>Table L-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/></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/></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/></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/></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/></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/></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/></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/></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/></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/></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/></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>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>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 name="d3e18555" id="d3e18555"/>K.2 Guidelines</h3><table summary="HTML Table" id="qa-framework-guidelines-table" class="common"><caption>Table L-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/></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/></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/></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>NO</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/></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/></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/></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>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/></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>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/></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>NO</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/></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/></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/></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/></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/></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/></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/></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>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>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>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/></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 name="d3e18546" id="d3e18546"/>K.2 Guidelines</h3><table summary="HTML Table" id="qa-framework-guidelines-table" class="common"><caption>Table L-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/></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/></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/></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>NO</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/></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/></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/></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>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/></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>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/></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>NO</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/></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/></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/></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/></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/></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/></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/></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>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>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>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/></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
 <a href="#doctypes">TTML 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">
@@ -9004,4 +8956,27 @@
 * Update namespace URIs to use ns/ttml instead of 2006/10.
 * Changed the title of the document
 * Identified tts:dynamicFlow at risk
+</pre></div></div><div class="div2">
+<h3><a name="change-history-cr3-to-cr4" id="change-history-cr3-to-cr4"/>N.6 Changes from Third Candidate Recommendation to Fourth Candidate Recommendation</h3><div class="exampleInner"><pre>
+<span class="strong">Technical Changes</span>
+The following changes result in a technical change of the conformance
+criteria, the normative abstract document type that is defined
+for use with TTML, or the defined value space of an attribute or
+property:
+
+* Removed at risk features tts:dynamicFlow property, overflow: dynamic value, flowFunction and flowInternalFunction definitions 
+* Removed Appendix on Dynamic Flow Processing Model 
+* Removed profile features: #rollUp, #dynamicFlow, #dynamicFlow-*, #overflow-dynamic, #rollup
+* Removed requirements R307, R501 
+* Changed content model of &lt;style&gt; element to EMPTY
+
+<span class="strong">Editorial Changes</span>
+The following changes are editorial in nature or entail semantic
+clarifications that do not affect the abstract document type, defined
+schemas, or conformance criteria for TTML:
+
+* replaced names TT AF and DFXP to TTML.
+* Changed wording on XSL model to clarify it as an exemplar and not a requirement
+* Removed informative notes on style attributes.
+
 </pre></div></div></div></div></body></html>
\ No newline at end of file
--- a/spec/ttaf1-dfxp.xml	Thu May 13 16:55:59 2010 +0000
+++ b/spec/ttaf1-dfxp.xml	Mon May 31 11:23:45 2010 +0000
@@ -1,13418 +1,13439 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!-- $Id$ -->
-<!DOCTYPE spec PUBLIC "-//W3C//DTD Specification V2.10//EN" "xmlspec-ttaf1-dfxp.dtd" [
-<!ENTITY % entities SYSTEM "entities.dtd" >
-%entities;
-<!ENTITY status SYSTEM "status.xml">
-<!ENTITY document.status "Editors' copy $Date$">
-<!ENTITY title "&title;">
-<!ENTITY prevloc "http://www.w3.org/TR/2010/CR-ttaf1-dfxp-20100223/">
-<!ENTITY versionOfTT "1.0">
-<!ENTITY tbd "<phrase role='tbd'>To Be Defined</phrase>">
-<!ENTITY sp "&#x0020;">
-<!ENTITY sect "&#x00a7;">
-<!ENTITY aring "&#x00e5;">
-<!ENTITY ccedil "&#x00e7;">
-<!ENTITY Ccedil "&#x00c7;">
-<!ENTITY mult "&#x00d7;">
-<!ENTITY uuml "&#x00fc;">
-<!ENTITY nbsp "&#x00a0;">
-<!ENTITY ndash "&#x2013;">
-<!ENTITY mdash "&#x2014;">
-<!ENTITY prime "&#x2032;">
-<!ENTITY hArr "&#x21d4;">
-<!ENTITY trade "&#x2122;">
-<!ENTITY hellip "&#x2026;">
-<!ENTITY isin "&#x2208;">
-<!ENTITY minus "&#x2212;">
-<!ENTITY le "&#x2264;">
-<!ENTITY ge "&#x2265;">
-<!ENTITY plusmn "&#x00B1;">
-<!ENTITY dfxp-ex1 SYSTEM "./examples/ex1.xml.esc">
-<!ENTITY dfxp-ex1-x-0 SYSTEM "./examples/ex1-x-0.xml.esc">
-<!ENTITY dfxp-ex1-p-0 SYSTEM "./examples/ex1-p-0.xml.esc">
-<!ENTITY dfxp-ex1-x-1 SYSTEM "./examples/ex1-x-1.xml.esc">
-<!ENTITY dfxp-ex1-x-2 SYSTEM "./examples/ex1-x-2.xml.esc">
-<!ENTITY rnc-dfxp-driver SYSTEM "./rnc/ttaf1-dfxp.rnc.esc">
-<!ENTITY rnc-dfxp-animation-module SYSTEM "./rnc/ttaf1-dfxp-animation.rnc.esc">
-<!ENTITY rnc-dfxp-classes-module SYSTEM "./rnc/ttaf1-dfxp-classes.rnc.esc">
-<!ENTITY rnc-dfxp-content-module SYSTEM "./rnc/ttaf1-dfxp-content.rnc.esc">
-<!ENTITY rnc-dfxp-core-attribs-module SYSTEM "./rnc/ttaf1-dfxp-core-attribs.rnc.esc">
-<!ENTITY rnc-dfxp-datatypes-module SYSTEM "./rnc/ttaf1-dfxp-datatypes.rnc.esc">
-<!ENTITY rnc-dfxp-document-module SYSTEM "./rnc/ttaf1-dfxp-document.rnc.esc">
-<!ENTITY rnc-dfxp-head-module SYSTEM "./rnc/ttaf1-dfxp-head.rnc.esc">
-<!ENTITY rnc-dfxp-metadata-module SYSTEM "./rnc/ttaf1-dfxp-metadata.rnc.esc">
-<!ENTITY rnc-dfxp-metadata-items-module SYSTEM "./rnc/ttaf1-dfxp-metadata-items.rnc.esc">
-<!ENTITY rnc-dfxp-metadata-attribs-module SYSTEM "./rnc/ttaf1-dfxp-metadata-attribs.rnc.esc">
-<!ENTITY rnc-dfxp-parameters-module SYSTEM "./rnc/ttaf1-dfxp-parameters.rnc.esc">
-<!ENTITY rnc-dfxp-parameter-items-module SYSTEM "./rnc/ttaf1-dfxp-parameter-items.rnc.esc">
-<!ENTITY rnc-dfxp-parameter-attribs-module SYSTEM "./rnc/ttaf1-dfxp-parameter-attribs.rnc.esc">
-<!ENTITY rnc-dfxp-styling-attribs-module SYSTEM "./rnc/ttaf1-dfxp-styling-attribs.rnc.esc">
-<!ENTITY rnc-dfxp-styling-module SYSTEM "./rnc/ttaf1-dfxp-styling.rnc.esc">
-<!ENTITY rnc-dfxp-layout-module SYSTEM "./rnc/ttaf1-dfxp-layout.rnc.esc">
-<!ENTITY rnc-dfxp-timing-attribs-module SYSTEM "./rnc/ttaf1-dfxp-timing-attribs.rnc.esc">
-<!ENTITY xsd-dfxp-driver SYSTEM "./xsd/ttaf1-dfxp.xsd.esc">
-<!ENTITY xsd-dfxp-animation-module SYSTEM "./xsd/ttaf1-dfxp-animation.xsd.esc">
-<!ENTITY xsd-dfxp-content-module SYSTEM "./xsd/ttaf1-dfxp-content.xsd.esc">
-<!ENTITY xsd-dfxp-core-attribs-module SYSTEM "./xsd/ttaf1-dfxp-core-attribs.xsd.esc">
-<!ENTITY xsd-dfxp-datatypes-module SYSTEM "./xsd/ttaf1-dfxp-datatypes.xsd.esc">
-<!ENTITY xsd-dfxp-document-module SYSTEM "./xsd/ttaf1-dfxp-document.xsd.esc">
-<!ENTITY xsd-dfxp-head-module SYSTEM "./xsd/ttaf1-dfxp-head.xsd.esc">
-<!ENTITY xsd-dfxp-metadata-module SYSTEM "./xsd/ttaf1-dfxp-metadata.xsd.esc">
-<!ENTITY xsd-dfxp-metadata-items-module SYSTEM "./xsd/ttaf1-dfxp-metadata-items.xsd.esc">
-<!ENTITY xsd-dfxp-metadata-attribs-module SYSTEM "./xsd/ttaf1-dfxp-metadata-attribs.xsd.esc">
-<!ENTITY xsd-dfxp-parameters-module SYSTEM "./xsd/ttaf1-dfxp-parameters.xsd.esc">
-<!ENTITY xsd-dfxp-parameter-items-module SYSTEM "./xsd/ttaf1-dfxp-parameter-items.xsd.esc">
-<!ENTITY xsd-dfxp-parameter-attribs-module SYSTEM "./xsd/ttaf1-dfxp-parameter-attribs.xsd.esc">
-<!ENTITY xsd-dfxp-styling-attribs-module SYSTEM "./xsd/ttaf1-dfxp-styling-attribs.xsd.esc">
-<!ENTITY xsd-dfxp-styling-module SYSTEM "./xsd/ttaf1-dfxp-styling.xsd.esc">
-<!ENTITY xsd-dfxp-layout-module SYSTEM "./xsd/ttaf1-dfxp-layout.xsd.esc">
-<!ENTITY xsd-dfxp-timing-attribs-module SYSTEM "./xsd/ttaf1-dfxp-timing-attribs.xsd.esc">
-<!ENTITY xsd-dfxp-xml-attrs-module SYSTEM "./xsd/xml.xsd.esc">
-<!ENTITY profile-dfxp-presentation SYSTEM "./profiles/dfxp-presentation.xml.esc">
-<!ENTITY profile-dfxp-transformation SYSTEM "./profiles/dfxp-transformation.xml.esc">
-<!ENTITY profile-dfxp-full SYSTEM "./profiles/dfxp-full.xml.esc">
-]>
-<?xml-stylesheet type='text/xsl' href='xmlspec-ttaf1-dfxp.xsl'?>
-<spec w3c-doctype="&doctype;" role="&document.role;">
-<header>
-<title>&title;</title>
-<w3c-designation>&w3c-designation;</w3c-designation>
-<w3c-doctype>&document.status;</w3c-doctype>
-<pubdate>
-<day>&draft.day;</day>
-<month>&draft.month;</month>
-<year>&draft.year;</year>
-</pubdate>
-<publoc>
-<loc href="&w3c-designation;">&w3c-designation;</loc>
-</publoc>
-<prevlocs>
-<loc href="&prevloc;">&prevloc;</loc>
-</prevlocs>
-<latestloc>
-<loc href="&latest;">&latest;</loc>
-</latestloc>
-<authlist id="editors" role="editor">
-<author>
-<name>Glenn Adams</name>
-<affiliation>Samsung Electronics Co., Ltd.</affiliation>
-</author>
-</authlist>
-<authlist id="contributors" role="contributor">
-<author>
-<name>Mike Dolan</name>
-<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>
-</author>
-<author>
-<name>David Kirby</name>
-<affiliation>British Broadcasting Corporation (BBC)</affiliation>
-</author>
-<author>
-<name>Thierry Michel</name>
-<affiliation>W3C</affiliation>
-</author>
-<author>
-<name>Dave Singer</name>
-<affiliation>Apple Computer</affiliation>
-</author>
-</authlist>
-<abstract id="abstract">
-<p>This document specifies the Timed Text Markup Language (TTML) in terms of a
-vocabulary and semantics thereof.</p>
-<p>The Timed Text Markup Language is a content type that represents
-timed text media for the purpose of interchange among authoring
-systems. Timed text is textual information that is intrinsically or
-extrinsically associated with timing information.</p>
-<p>It is intended to be used
-for the purpose of transcoding or exchanging timed text information
-among legacy distribution content formats presently in use for
-subtitling and captioning functions.</p>
-<p>In addition to being used for interchange among legacy distribution content
-formats, TTML content may be used directly as a distribution format,
-for example, providing a standard content format to reference from a <el>&lt;text&gt;</el> or 
-<el>&lt;textstream&gt;</el> media object element in a <bibref
-ref="smil21"/> document.</p>
-</abstract>
-&status;
-<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>
-<p>The Timed Text Markup Language (TTML) 1.0
-provides a standardized representation of a particular subset of
-textual information with which stylistic, layout, and timing semantics are associated by
-an author or an authoring system for the purpose of interchange and potential presentation.</p>
-<p>TTML is expressly designed to meet only a limited set of requirements
-established by <bibref ref="ttaf1-req"/>, and summarized in <specref
-ref="requirements"/>. In particular, only those requirements which service the
-need of performing interchange with existing, legacy distribution systems are
-satisfied.</p>
-<p>In addition to being used for interchange among legacy distribution content
-formats, TTML content may be used directly as a distribution format, providing, for
-example, a standard content format to reference from a <el>&lt;text&gt;</el> or 
-<el>&lt;textstream&gt;</el> media object element in a <bibref
-ref="smil21"/> document. Certain properties of TTML support
-streamability of content, as described in <specref ref="streaming"/>.</p>
-<note>
-<p>While TTML was not expressly designed for direct (embedded) integration into a
-SMIL document instance, such integration is not precluded.</p>
-</note>
-<note>
-<p>In some contexts of use, it may be appropriate to employ
-animated content to depict sign language representations of the same content
-as expressed by a Timed Text document instance. This use case is not
-explicitly addressed by TTML mechanisms, but may be addressed by some
-external multimedia integration technology, such as SMIL.</p>
-</note>
-<div2 id="model">
-<head>System Model</head>
-<p>Use of TTML is intended to function in a wider context of Timed Text
-Authoring and Distribution mechanisms that are based upon a system
-model, depicted in <specref ref="model-graphic"/>, wherein the Timed Text Markup Language
-serves as a bidirectional interchange format among a heterogeneous collection of
-authoring systems, and as a unidirectional interchange format to a
-heterogeneous collection of distribution formats after undergoing transcoding
-or compilation to the target distribution formats as required, and where one
-particular distribution format is TTML.</p>
-<table id="model-graphic" role="example-images">
-<caption>Figure 1 &ndash; System Model</caption>
-<tbody>
-<tr>
-<td><graphic id="graphic-model" source="images/model.png" alt="System Model"/></td>
-</tr>
-</tbody>
-</table>
-</div2>
-<div2 id="example">
-<head>Document Example</head>
-<p>A TTML document instance consists of a <el>tt</el> document element that contains
-a header and a body, where the header specifies document level metadata, styling
-definitions and layout definitions, and the body specifies text content intermixed
-with references to style and layout information and inline timing information.</p>
-<table id="dfxp-example-document-structure" role="example">
-<caption>Example Fragment &ndash; TTML Document Structure</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;tt xml:lang="" xmlns="http://www.w3.org/ns/ttml"&gt;
-  &lt;head&gt;
-    &lt;metadata/&gt;
-    &lt;styling/&gt;
-    &lt;layout/&gt;
-  &lt;/head&gt;
-  &lt;body/&gt;
-&lt;/tt&gt;
-</eg>
-</td></tr>
-</tbody>
-</table>
-<p>Document level metadata may specify a document title, description,
-and copyright information. In addition, arbitrary metadata drawn from
-other namespaces may be specified.</p>
-<table id="dfxp-example-metadata" role="example">
-<caption>Example Fragment &ndash; TTML Metadata</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;metadata xmlns:ttm="http://www.w3.org/ns/ttml#metadata"&gt;
-  &lt;ttm:title&gt;Timed Text TTML Example&lt;/ttm:title&gt;
-  &lt;ttm:copyright&gt;The Authors (c) 2006&lt;/ttm:copyright&gt;
-&lt;/metadata&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>Styling information may be specified in the form of style specification
-definitions that are referenced by layout and content information.</p>
-<p>In <specref ref="dfxp-example-styling"/>, four style sets of specifications
-are defined, with one set serving as a collection of default styles.</p>
-<table id="dfxp-example-styling" role="example">
-<caption>Example Fragment &ndash; TTML Styling</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;styling xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
-  &lt;!-- s1 specifies default color, font, and text alignment --&gt;
-  &lt;style xml:id="s1"
-    tts:color="white"
-    tts:fontFamily="proportionalSansSerif"
-    tts:fontSize="22px"
-    tts:textAlign="center"
-  /&gt;
-  &lt;!-- alternative using yellow text but otherwise the same as style s1 --&gt;
-  &lt;style xml:id="s2" style="s1" tts:color="yellow"/&gt;
-  &lt;!-- a style based on s1 but justified to the right --&gt;
-  &lt;style xml:id="s1Right" style="s1" tts:textAlign="end" /&gt;     
-  &lt;!-- a style based on s2 but justified to the left --&gt;
-  &lt;style xml:id="s2Left" style="s2" tts:textAlign="start" /&gt;
-&lt;/styling&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>Layout information defines one or more regions into which content
-is intended to be presented. A region definition may reference one or
-more sets of style specifications in order to permit content flowed in the
-region to inherit from these styles.
-In <specref ref="dfxp-example-layout"/>, the region definition makes
-reference to style specification <code>s1</code> which allows all content
-flowed into the region to inherit from the region's styles (in the case
-that a style is not already explicitly specified on content or inherited
-via the content hierarchy.)</p>
-<table id="dfxp-example-layout" role="example">
-<caption>Example Fragment &ndash; TTML Layout</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;layout xmlns:tts="http://www.w3.org/ns/ttml#styling"&gt;
-  &lt;region xml:id="subtitleArea"
-    style="s1"
-    tts:extent="560px 62px"
-    tts:padding="5px 3px"
-    tts:backgroundColor="black"
-    tts:displayAlign="after"
-  /&gt;
-&lt;/layout&gt;  
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>The content of a TTML document instance is expressed in its
-body, which is organized in terms of block and inline text elements.
-The hierarchical organization of content elements serves a primary role in
-determining both spatial and temporal relationships. For example, in
-<specref ref="dfxp-example-body"/>, each paragraph (<el>p</el> element)
-is flowed into its target region in the specified lexical order; furthermore,
-the active time interval of each paragraph is timed in accordance to its
-parent or sibling according to the applicable time containment semantics &mdash;
-in this case, the division parent is interpreted as a parallel time
-container.</p>
-<table id="dfxp-example-body" role="example">
-<caption>Example Fragment &ndash; TTML Body</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;body region="subtitleArea"&gt;
-  &lt;div&gt;
-    &lt;p xml:id="subtitle1" begin="0.76s" end="3.45s"&gt;
-      It seems a paradox, does it not,
-    &lt;/p&gt;
-    &lt;p xml:id="subtitle2" begin="5.0s" end="10.0s"&gt;
-      that the image formed on&lt;br/&gt;
-      the Retina should be inverted?
-    &lt;/p&gt;
-    &lt;p xml:id="subtitle3" begin="10.0s" end="16.0s" style="s2"&gt;
-      It is puzzling, why is it&lt;br/&gt;
-      we do not see things upside-down?
-    &lt;/p&gt;
-    &lt;p xml:id="subtitle4" begin="17.2s" end="23.0s"&gt;
-      You have never heard the Theory,&lt;br/&gt;
-      then, that the Brain also is inverted?
-    &lt;/p&gt;
-    &lt;p xml:id="subtitle5" begin="23.0s" end="27.0s" style="s2"&gt;
-      No indeed! What a beautiful fact!
-    &lt;/p&gt;
-    &lt;p xml:id="subtitle6a" begin="28.0s" end="34.6s" style="s2Left"&gt;
-      But how is it proved?
-    &lt;/p&gt;
-    &lt;p xml:id="subtitle6b" begin="28.0s" end="34.6s" style="s1Right"&gt;
-      Thus: what we call
-    &lt;/p&gt;
-    &lt;p xml:id="subtitle7" begin="34.6s" end="45.0s" style="s1Right"&gt;
-      the vertex of the Brain&lt;br/&gt;
-      is really its base
-    &lt;/p&gt;
-    &lt;p xml:id="subtitle8" begin="45.0s" end="52.0s" style="s1Right"&gt;
-      and what we call its base&lt;br/&gt;
-      is really its vertex,
-    &lt;/p&gt;
-    &lt;p xml:id="subtitle9a" begin="53.5s" end="58.7s"&gt;
-      it is simply a question of nomenclature.
-    &lt;/p&gt;
-    &lt;p xml:id="subtitle9b" begin="53.5s" end="58.7s" style="s2"&gt;
-      How truly delightful!
-    &lt;/p&gt;
-  &lt;/div&gt;    
-&lt;/body&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>The first subtitle <specref ref="dfxp-example-subtitle-1"/> is
-presented during the time interval 0.76 to 3.45 seconds.
-This
-subtitle inherits its font family, font size,
-foreground color, and text alignment from the region into which it is
-presented. Since no region is explicitly specified on the paragraph,
-the nearest ancestor that specifies a region determines the
-region. Note also that content is presented
-at the bottom (after edge) of the containing region due to the <code>tts:displayAlign="after"</code>
-being specified on the region definition.</p>
-<note role="explanation">
-<p>The notation "[<emph>X</emph>,<emph>Y</emph>]" denotes a closed
-interval from <emph>X</emph> to <emph>Y</emph>, including
-<emph>X</emph> and <emph>Y</emph>;
-"[<emph>X</emph>,<emph>Y</emph>)" denotes a right half-open
-interval from <emph>X</emph> to <emph>Y</emph>, including
-<emph>X</emph> but not including <emph>Y</emph>;
-"(<emph>X</emph>,<emph>Y</emph>]" denotes a left half-open
-interval from <emph>X</emph> to <emph>Y</emph>, not including
-<emph>X</emph> but including <emph>Y</emph>;
-"(<emph>X</emph>,<emph>Y</emph>)" denotes an open
-interval from <emph>X</emph> to <emph>Y</emph>, not including
-<emph>X</emph> or <emph>Y</emph>.
-</p>
-</note>
-<table id="dfxp-example-subtitle-1" role="example-images">
-<caption>Subtitle 1 &ndash; Time Interval [0.76, 3.45)</caption>
-<tbody>
-<tr>
-<td><graphic source="images/subtitle1.png" alt="Subtitle 1"/></td>
-</tr>
-</tbody>
-</table>
-<p>The second subtitle continues with the default style, except that it contains
-two lines of text with an intervening author-specified line break. Note the effects of
-the use of <code>tts:textAlign="center"</code> to specify the paragraph's alignment
-in the inline progression direction.</p>
-<table id="dfxp-example-subtitle-2" role="example-images">
-<caption>Subtitle 2 &ndash; Time Interval [5.0, 10.0)</caption>
-<tbody>
-<tr>
-<td><graphic source="images/subtitle2.png" alt="Subtitle 2"/></td>
-</tr>
-</tbody>
-</table>
-<p>The third subtitle continues, using a variant style which overrides the default style's
-foreground color with a different color.</p>
-<table id="dfxp-example-subtitle-3" role="example-images">
-<caption>Subtitle 3 &ndash; Time Interval [10.0, 16.0)</caption>
-<tbody>
-<tr>
-<td><graphic source="images/subtitle3.png" alt="Subtitle 3"/></td>
-</tr>
-</tbody>
-</table>
-<p>The fourth subtitle reverts to the default style.</p>
-<table id="dfxp-example-subtitle-4" role="example-images">
-<caption>Subtitle 4 &ndash; Time Interval [17.2, 23.0)</caption>
-<tbody>
-<tr>
-<td><graphic source="images/subtitle4.png" alt="Subtitle 4"/></td>
-</tr>
-</tbody>
-</table>
-<p>The fifth subtitle continues, again using a variant style which
-overrides the default style's foreground color with a different color.</p>
-<table id="dfxp-example-subtitle-5" role="example-images">
-<caption>Subtitle 5 &ndash; Time Interval [23.0, 27.0)</caption>
-<tbody>
-<tr>
-<td><graphic source="images/subtitle5.png" alt="Subtitle 5"/></td>
-</tr>
-</tbody>
-</table>
-<p>During the next active time interval, two distinct subtitles are simultaneously active, with
-the paragraph expressing each subtitle using a different style that overrides color and paragraph
-text alignment of the default style. Note that the flow order is determined by the lexical
-order of elements as they appear in the content hierarchy.</p>
-<table id="dfxp-example-subtitle-6" role="example-images">
-<caption>Subtitles 6a and 6b &ndash; Time Interval [28.0, 34.6)</caption>
-<tbody>
-<tr>
-<td><graphic source="images/subtitle6.png" alt="Subtitles 6a and 6b"/></td>
-</tr>
-</tbody>
-</table>
-<p>The next subtitle is specified in a similar manner using
-a style override to give a paragraph right (end) justified in the
-inline progression direction.</p>
-<table id="dfxp-example-subtitle-7" role="example-images">
-<caption>Subtitle 7 &ndash; Time Interval [34.6, 45.0)</caption>
-<tbody>
-<tr>
-<td><graphic source="images/subtitle7.png" alt="Subtitles 7a and 7b"/></td>
-</tr>
-</tbody>
-</table>
-<p>The eighth subtitle uses the same style override as the previous
-subtitle in order to maintain the right (end) justification of the
-paragraph.</p>
-<table id="dfxp-example-subtitle-8" role="example-images">
-<caption>Subtitle 8 &ndash; Time Interval [47.3, 49.0)</caption>
-<tbody>
-<tr>
-<td><graphic source="images/subtitle8.png" alt="Subtitle 8"/></td>
-</tr>
-</tbody>
-</table>
-<p>During the final (ninth) active time interval, two distinct
-subtitles are again simultaneously active, but with a different
-style applied to the second paragraph to override the default color.
-Note that the flow order is determined by the lexical order of
-elements as they appear in the content hierarchy.</p>
-<table id="dfxp-example-subtitle-9" role="example-images">
-<caption>Subtitles 9a and 9b &ndash; Time Interval [53.5, 58.7)</caption>
-<tbody>
-<tr>
-<td><graphic source="images/subtitle9.png" alt="Subtitles 9a and 9b"/></td>
-</tr>
-</tbody>
-</table>
-<p>The examples shown above demonstrate the primary types of information that may
-be authored using TTML: metadata, styling, layout, timing, and content. In typical cases,
-styling and layout information are separately specified in a document instance. Content information
-is expressed in a hierarchical fashion that embodies the organization of both spatial (flow) and
-timing information. Content makes direct or indirect references to styling and layout information
-and may specify inline overrides to styling.</p>
-</div2>
-</div1>
-<div1 id="definitions">
-<head>Definitions</head>
-<div2 id="acronyms">
-<head>Acronyms</head>
-<glist role="acronyms">
-<gitem>
-<label>DFXP</label>
-<def>
-<p>Distribution Format Exchange Profile</p>
-</def>
-</gitem>
-<gitem>
-<label>TT</label>
-<def>
-<p>Timed Text</p>
-</def>
-</gitem>
-  <gitem>
-    <label>TTML</label>
-    <def>
-      <p>Timed Text Markup Language</p>
-    </def>
-  </gitem>
-  <gitem>
-<label>TT AS</label>
-<def>
-<p>Timed Text Authoring System</p>
-</def>
-</gitem>
-<gitem>
-<label>TT AF</label>
-<def>
-<p>Timed Text Authoring Format</p>
-</def>
-</gitem>
-<gitem>
-<label>TT WG</label>
-<def>
-<p>Timed Text Working Group</p>
-</def>
-</gitem>
-</glist>
-</div2>
-<div2 id="terms">
-<head>Terminology</head>
-<glist>
-<gitem>
-<label>Abstract Document Instance</label>
-<def>
-<p>An instance of an abstract data set as represented by a
-<emph>Reduced XML Infoset</emph>.</p>
-</def>
-</gitem>
-<gitem>
-<label>Abstract Document Type</label>
-<def>
-<p>A set of constraints that defines a class of <emph>XML Information
-Set</emph>s <bibref ref="infoset"/>.</p>
-</def>
-</gitem>
-<gitem>
-<label>Attribute Information Item</label>
-<def>
-<p>Each specified or defaulted attribute  of an XML document corresponds with an attribute information
-item as defined by <bibref ref="infoset"/>, &sect;2.3.</p>
-</def>
-</gitem>
-<gitem>
-<label>Character Information Item</label>
-<def>
-<p>Each data character appearing in an XML document corresponds with a character information
-item as defined by <bibref ref="infoset"/>, &sect;2.6.</p>
-</def>
-</gitem>
-<gitem>
-<label>Content Processor</label>
-<def>
-<p>A processing system capable of importing (receiving) Timed Text Markup Language
-content for the purpose of transforming, presenting, or otherwise processing the content.</p>
-</def>
-</gitem>
-<gitem>
-<label>Content Profile</label>
-<def>
-<p>A collection of features and extensions that are (or may be) employed by
-Timed Text Markup Language content.</p>
-</def>
-</gitem>
-<gitem>
-<label>Content Region</label>
-<def>
-<p>A logical region into which rendered content is placed when modeling or
-performing presentation processing.</p>
-</def>
-</gitem>
-<gitem>
-<label>Element Information Item</label>
-<def>
-<p>Each element appearing in an XML document corresponds with an element information
-item as defined by <bibref ref="infoset"/>, &sect;2.2.</p>
-</def>
-</gitem>
-<gitem>
-<label>Exchange Profile</label>
-<def>
-<p>A content profile that serves a set of needs
-for content interchange.</p>
-</def>
-</gitem>
-<gitem>
-<label>Extension</label>
-<def>
-<p>A syntactic or semantic expression or capability that is defined and
-labeled (using a extension designation) in another (public or private)
-specification.</p>
-</def>
-</gitem>
-<gitem>
-<label>Feature</label>
-<def>
-<p>A syntactic or semantic expression or capability that is defined and
-labeled (using a feature designation) in this specification (or a
-future revision of this specification).</p>
-</def>
-</gitem>
-<gitem>
-<label>Processor</label>
-<def>
-<p>See <emph>Content Processor</emph>.</p>
-</def>
-</gitem>
-<gitem>
-<label>Processor Profile</label>
-<def>
-<p>A collection of features and extensions that must or may be implemented (supported) by
-a content processor.</p>
-</def>
-</gitem>
-<gitem>
-<label>Profile Definition Document</label>
-<def>
-<p>A document that defines a specific collection of features and extensions
-for which support is required or optional in a recipient content
-processor.</p>
-</def>
-</gitem>
-<gitem>
-<label>Region</label>
-<def>
-<p>A logical construct that models authorial intention regarding
-desired or potential presentation processing, and which is represented as
-a rectangular area of a presentation surface into which content
-is composed and rendered during presentation processing.</p>
-</def>
-</gitem>
-<gitem>
-<label>Reduced XML Infoset</label>
-<def>
-<p>An XML Information Set <bibref ref="infoset"/> that satisfieds the
-constraints specify by <specref ref="reduced-infoset"/>.</p>
-</def>
-</gitem>
-<gitem>
-<label>Root Container Region</label>
-<def>
-<p>A logical region that establishes a coordinate system into which
-content regions are placed and optionally clipped.</p>
-</def>
-</gitem>
-<gitem>
-<label>Timed Text</label>
-<def>
-<p>Textual information that is intrinsically or extrinsically
-associated with timing information.</p>
-</def>
-</gitem>
-<gitem>
-<label>Timed Text Markup Language</label>
-<def>
-<p>A content type that represents timed text media for the purpose of
-interchange among authoring systems.</p>
-</def>
-</gitem>
-<gitem>
-<label>Timed Text Authoring System</label>
-<def>
-<p>A content authoring system capable of importing and exporting
-Timed Text Markup Language content.</p>
-</def>
-</gitem>
-</glist>
-</div2>
-<div2 id="conventions">
-<head>Documentation Conventions</head>
-<p>Within normative prose in this specification, the words
-<emph>may</emph>, <emph>should</emph>, and <emph>must</emph> are
-defined as follows:</p>
-<glist role="conformance-keywords">
-<gitem>
-<label>may</label>
-<def>
-<p>Conforming documents and/or TTML processors are permitted to,
-but need not behave as described. </p>
-</def>
-</gitem>
-<gitem>
-<label>should</label>
-<def>
-<p>Conforming documents and/or TTML processors are strongly
-recommended to, but need not behave as described.</p>
-</def>
-</gitem>
-<gitem>
-<label>must</label>
-<def>
-<p>Conforming documents and/or TTML processors are required
-to behave as described; otherwise, they are in error. </p>
-</def>
-</gitem>
-</glist>
-<p>All normative syntactic definitions of XML representations and
-other related terms are depicted with a light orange background color
-and labeled as "XML Representation" or "Syntax Representation", such
-as in the following:</p>
-<table id="elt-syntax-example" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: example</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;example
-  <phrase role="reqattr">count</phrase> = integer
-  size = (<emph>large</emph>|<emph>medium</emph>|<emph>small</emph>) : medium&gt;
-  <emph>Content:</emph> (all | any*)
-&lt;/example&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>In an XML representation, bold-face attribute names (e.g. <phrase
-role="strong">count</phrase> above) indicate a required attribute
-information item, and the rest are optional. Where an attribute
-information item has an enumerated type definition, the values are
-shown separated by vertical bars, as for <code>size</code> above; if
-there is a default value, it is shown following a colon. Where an
-attribute information item has a built-in simple type definition
-defined in <bibref ref="xsd-2"/>, a hyperlink to its definition
-therein is given.</p>
-<p>The allowed content of the information item is shown as a grammar
-fragment, using the Kleene operators <code>?</code>, <code>*</code>
-and <code>+</code>. Each element name therein is a hyperlink to its
-own illustration.</p>
-<p>All content of this specification that is not explicitly marked as
-non-normative is considered to be normative. If a section or appendix
-header contains the expression "Non-Normative", then the entirety
-of the section or appendix is considered non-normative.</p>
-<p>All paragraphs marked as a <phrase role="strong">Note</phrase> are considered non-normative.</p>
-<p>Example code fragments are depicted with a light blue-green
-background color and labeled as "Example Fragment", such as in
-the following:</p>
-<table id="example-fragment-1" role="example">
-<caption>Example Fragment &ndash; Sample</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;tt xml:lang="" xmlns="http://www.w3.org/ns/ttml"&gt;
-  &lt;head&gt;
-    &lt;metadata/&gt;
-    &lt;styling/&gt;
-    &lt;layout/&gt;
-  &lt;/head&gt;
-  &lt;body/&gt;
-&lt;/tt&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-</div2>
-</div1>
-<div1 id="conformance">
-<head>Conformance</head>
-<p>This section specifies the general conformance requirements for
-TTML content and processors.</p>
-<div2 id="conformance-content">
-<head>Content Conformance</head>
-<p>A TTML document instance conforms to this specification if the following criteria are
-satisfied:</p>
-<olist>
-<item>
-<p>When transporting a document instance in a context in which a MIME
-Media Type <bibref ref="mime-media"/> identifies the content type of the interchanged document
-instance, then the specified media type is
-<code>application/ttml+xml</code> in conformance with <bibref
-ref="rfc3023"/> &sect; 7, with which an optional
-<code>profile</code> parameter may appear, the value of which
-conforms to
-a profile designator as
-defined by
-<specref ref="vocabulary-profiles"/>.</p>
-</item>
-<item>
-<p>The document instance is or can be represented as a Reduced XML
-Infoset as defined by <specref ref="reduced-infoset"/>.</p>
-</item>
-<item>
-<p>The Reduced XML
-Infoset that corresponds to the document instance is or can
-be associated with one of the TTML Abstract
-Document Types defined by
-<specref ref="doctypes"/>.</p>
-</item>
-<item>
-<p>The Reduced XML Infoset that corresponds to the document instance is a
-Valid Abstract Document Instance of the associated
-Abstract Document Type.</p>
-</item>
-<item>
-<p>The Reduced XML Infoset satisfies all additional mandatory syntactic and
-semantic constraints defined by this specification. In addition, this Infoset
-should satisfy the web content accessibility guidelines specified by
-<bibref ref="wcag"/>.</p>
-</item>
-</olist>
-</div2>
-<div2 id="conformance-processor">
-<head>Processor Conformance</head>
-<div3 id="conformance-generic-processor">
-<head>Generic Processor Conformance</head>
-<p>A TTML processor conforms to this specification if the following
-generic processor criteria are
-satisfied:</p>
-<olist>
-<item>
-<p>The processor provides at least one mechanism for notionally
-instantiating a Reduced XML
-Infoset representation of a conformant TTML document
-instance.</p>
-</item>
-<item>
-<p>If a process does or can perform validation of a candidate TTML
-document instance, then it provides at least one mechanism to
-implicitly or explicitly associate the
-Reduced XML Infoset representation
-of a conformant TTML document instance with one of the
-TTML Abstract Document Types defined by
-<specref ref="doctypes"/>.</p>
-</item>
-<item>
-<p>The processor does not <emph>a priori</emph> reject or abort the
-processing of a conformant TTML document instance
-unless the processor does not support some required
-(mandatory) feature specified or implied by a TTML content profile
-declared to apply to the document instance.</p>
-</item>
-<item>
-<p>The processor supports all mandatory processing semantics defined by this specification.</p>
-</item>
-<item>
-<p>If the processor supports some optional processing semantics defined by this specification,
-then it does so in a manner consistent with the defined semantics.</p>
-</item>
-</olist>
-</div3>
-<div3 id="conformance-transformation-processor">
-<head>Transformation Processor Conformance</head>
-<p>A TTML processor is a conformant TTML transformation processor if
-the following criteria are satisfied:</p>
-<olist>
-<item>
-<p>The processor satisfies all requirements specified by
-<specref ref="conformance-generic-processor"/>.</p>
-</item>
-<item>
-<p>The processor supports the DFXP Transformation profile as specified
-by <specref ref="profile-dfxp-transformation"/>.</p>
-</item>
-</olist>
-</div3>
-<div3 id="conformance-presentation-processor">
-<head>Presentation Processor Conformance</head>
-<olist>
-<item>
-<p>The processor satisfies all requirements specified by
-<specref ref="conformance-generic-processor"/>.</p>
-</item>
-<item>
-<p>The processor supports the DFXP Presentation profile as specified
-by <specref ref="profile-dfxp-presentation"/>.</p>
-</item>
-</olist>
-</div3>
-</div2>
-<div2 id="claims">
-<head>Claims</head>
-<p>Any claim of compliance with respect to TTML content or processor
-conformance must make
-reference to an implementation compliance statement (ICS).</p>
-<p>An implementation compliance statement must identify all mandatory
-and optional features of this specification that are satisfied by the
-content or processor implementation. In particular, the statement must
-identify the utilized or supported TTML vocabulary profile(s) as
-defined by <specref ref="vocabulary-profiles"/>, and, if a subset or
-superset profile is used or supported, then what features are excluded
-or included in the subset or superset profile.</p>
-<p>A TTML document instance for which a compliance claim is made
-must specify
-either (1)
-a <att>ttp:profile</att> attribute on its root
-<el>tt</el>
-element
-as defined by <specref ref="parameter-attribute-profile"/>
-or (2)
-a <el>ttp:profile</el> element as a child of the
-<el>head</el> element as defined by
-<specref ref="parameter-vocabulary-profile"/>.</p>
-</div2>
-</div1>
-<div1 id="doctypes">
-<head>Document Types</head>
-<p>This section defines the following TTML Abstract Document Types:</p>
-<ulist>
-<item><p><specref ref="dfxp-content-doctype"/></p></item>
-</ulist>
-<p>Each abstract document type consists of the following constraints:</p>
-<ulist>
-<item><p>a non-empty collection of element types, where each element type consists of a name,
-a (possibly empty) collection of attributes, and a content specification</p></item>
-<item><p>a non-empty collection of element types that may appear as the document element</p></item>
-</ulist>
-<p>An Abstract Document Instance may be assessed in terms of validity,
-and is considered to be a Valid Abstract Document Instance if it
-satisfies the following condition: if after</p>
-<olist>
-<item>
-<p>pruning all element information
-items whose names are not members of the collection of element types defined
-by the associated abstract document type, then</p>
-</item>
-<item>
-<p>pruning character
-information item children from any remaining element in case that all
-character children of the element denote XML whitespace characters and the element's type
-is defined as empty in the associated Abstract Document Type, and then</p>
-</item>
-<item>
-<p>pruning all attribute
-information items having expanded names such that the namespace URI of the
-expanded names are not listed in <specref
-ref="namespace-vocab-table"/>,</p>
-</item>
-</olist>
-<p>then the document element is one of the document
-element types permitted by the associated abstract document type,
-the descendants of the document
-element satisfy their respective element type's content
-specifications, all required attributes are present, and the declared
-value of each attribute satisfies the type declared by the
-associated abstract document type.</p>
-<note>
-<p>While a conformant processor may not <emph>a priori</emph> reject a
-conformant document instance that adheres to a
-supported content profile, a given document instance may be
-constrained by the author or authoring tool to satisfy a more
-restrictive definition of validity.</p>
-</note>
-<div2 id="dfxp-content-doctype">
-<head>DFXP Content</head>
-<p>DFXP Content is an abstract document type of a profile of the Timed Text Markup Language intended
-to be used for interchange among distribution systems. This document type
-is defined in terms of the
-element and attribute vocabulary
-specified in <specref ref="vocabulary"/>.</p>
-<p>This specification defines two types of normative schemas that may be used to validate a subset of
-conformant DFXP Content document instances:</p>
-<ulist>
-<item><p><specref ref="dfxp-schema-rnc"/></p></item>
-<item><p><specref ref="dfxp-schema-xsd"/></p></item>
-</ulist>
-<p>The (root) document element of a DFXP Content document instance must be a
-<el>tt</el> element, as defined by <specref
-ref="document-structure-vocabulary-tt"/>.</p>
-<note role="clarification">
-<p>The schemas included in this specification do not validate all syntactic constraints
-defined by this specification. In particular, performing validation with one of the above
-referenced schemas may result in a <emph>false positive</emph> indication of validity.
-However, with one exception, their
-use will not produce a <emph>false negative</emph> indication of validity
-when used with a compliant validating
-processor.</p>
-<p>In exception to the above statement about false negatives,
-if the Relax NG schema included in this specification is used to validate a
-TTML Document containing elements in a foreign namespace and the <att>xml:id</att>
-attribute is used with any of those (foreign) elements,
-then an error will be reported even though such usage is permitted by this
-specification. In this case, the false negative arises due
-to a specific limitation in expressing wildcard patterns involving <code>xsd:ID</code>
-typed attributes in Relax NG schemas.
-Note that this specification defines the formal validity of a TTML Document to be
-based on an abstract document instance from which all foreign namespace elements and
-attributes have been removed. Therefore, the exceptional reporting of this false
-negative does not impact the formal assessment of TTML Document validity.</p>
-</note>
-</div2>
-</div1>
-<div1 id="vocabulary">
-<head>Vocabulary</head>
-<p>This section defines the
-namespaces, profiles, and vocabulary (as an element an attribute
-catalog) of the Timed Text Markup Language (TTML) as follows:</p>
-<ulist>
-<item><p><specref ref="vocabulary-namespaces"/></p></item>
-<item><p><specref ref="vocabulary-profiles"/></p></item>
-<item><p><specref ref="vocabulary-overview"/></p></item>
-</ulist>
-<div2 id="vocabulary-namespaces">
-<head>Namespaces</head>
-<p>The Timed Text Markup Language (TTML) employs a number of
-namespaces for elements and certain
-global attributes. The following table specifies this set of namespaces
-and indicates the default prefix used within this specification and the
-normative URI that denotes each namespace.</p>
-<note role="explanation">
-<p>In a specific document instance, it is not required that the default
-prefixes shown below are used. Any prefix or namespace binding that satisfies the constraints
-of XML Namespaces may be used that is associated with the specified namespace URI.</p>
-</note>
-<table id="namespace-vocab-table" role="common">
-<caption>Table 1 &ndash; Namespaces</caption>
-<col width="30%"/>
-<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><emph>none</emph></td>
-<td><code>http://www.w3.org/ns/ttml/profile/</code></td>
-</tr>
-<tr>
-<td>TT Feature</td>
-<td><emph>none</emph></td>
-<td><code>http://www.w3.org/ns/ttml/feature/</code></td>
-</tr>
-<tr>
-<td>TT Extension</td>
-<td><emph>none</emph></td>
-<td><code>http://www.w3.org/ns/ttml/extension/</code></td>
-</tr>
-</tbody>
-</table>
-<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>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
-future version of this specification). In such cases, the use of the
-namespace URI is for purposes other than defining XML vocabulary,
-e.g., for designating profiles, features, extensions and for
-dereferencing standard profile definitions.</p>
-</note>
-<p>All TTML Namespaces are <loc
-href="http://www.w3.org/2001/tag/doc/namespaceState#namespacedef"><emph>mutable</emph></loc>
-<bibref ref="nsstate"/>; all undefined names in these namespaces are reserved for future
-standardization by the W3C.</p>
-</div2>
-<div2 id="vocabulary-profiles">
-<head>Profiles</head>
-<p>The Timed Text Markup Language (TTML) employs a number of
-standard, predefined profiles of its
-vocabulary and associated semantics.
-The following table specifies this set of
-profiles, indicating
-a normative name
-and designator for each
-predefined profile,
-and where each of these profiles is formally elaborated in
-<specref ref="profiles"/>.</p>
-<table id="profile-vocab-table" role="common">
-<caption>Table 2 &ndash; Profiles</caption>
-<col width="25%"/>
-<tbody>
-<tr>
-<th>Name</th>
-<th>Designator</th>
-</tr>
-<tr>
-<td>DFXP Transformation</td>
-<td><code>http://www.w3.org/ns/ttml/profile/dfxp-transformation</code></td>
-</tr>
-<tr>
-<td>DFXP Presentation</td>
-<td><code>http://www.w3.org/ns/ttml/profile/dfxp-presentation</code></td>
-</tr>
-<tr>
-<td>DFXP Full</td>
-<td><code>http://www.w3.org/ns/ttml/profile/dfxp-full</code></td>
-</tr>
-</tbody>
-</table>
-<p/>
-<p>A profile designator must adhere to the
-<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,
-then it must be absolutized by using the TT Profile Namespace value as
-the base URI.</p>
-<note role="example">
-<p>For example, if a profile designator is expressed as
-<code>dfxp-presentation</code>, then the absolutized profile designator
-would be
-<code>http://www.w3.org/ns/ttml/profile/dfxp-presentation</code>.</p>
-</note>
-<p>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 Profile Definition Document.</p>
-<p>The profile of TTML that must be supported by a
-TTML content processor in order to process a document
-instance is specified either (1) by specifying a
-<att>ttp:profile</att> attribute on the root <el>tt</el> element, as
-defined by <specref ref="parameter-attribute-profile"/>, or (2) by
-including one or more <el>ttp:profile</el>
-elements in the <el>head</el> element, in
-accordance with <specref ref="parameter-vocabulary-profile"/>.</p>
-<p>If a <el>ttp:profile</el> element appears as a
-descendant of the <el>tt</el> element, then the <loc
-href="#parameter-attribute-profile"><att>ttp:profile</att></loc>
-attribute should not be specified on the <el>tt</el> element. If both
-a <el>ttp:profile</el> element and a <att>ttp:profile</att>
-attribute are present (in a given document instance), then the
-<att>ttp:profile</att> attribute must be ignored for the purpose of
-determining the declared profile requirements.</p>
-<p>If more than one <el>ttp:profile</el> element appears in
-a TTML document instance, then all specified profiles apply
-simultaneously.  In such a case, if some feature or some extension is
-specified by one profile to be used (mandatory and enabled) and by
-another profile to be required (mandatory) or optional (voluntary),
-then that feature or extension must be considered to be used
-(mandatory and enabled); if some feature or some extension is
-specified by one profile to be merely required (mandatory) and by
-another profile to be optional (voluntary), then that feature or
-extension must be considered to be required (mandatory).</p>
-<p>If neither
-<loc href="#parameter-attribute-profile"><att>ttp:profile</att></loc>
-attribute nor
-<loc href="#parameter-vocabulary-profile"><el>ttp:profile</el></loc>
-element is present in a TTML document instance, and if the document
-interchange context does not specify a profile,
-then the DFXP Transformation
-profile applies.</p>
-<note role="elaboration">
-<p>It is intended that the <att>ttp:profile</att> attribute be used when
-the author wishes to reference one of the standard, predefined profiles of
-TTML content, and does not wish to modify (by supersetting or subsetting)
-that profile. This attribute may also be used by an author to indicate the use
-of a non-standard profile, in which case the specified profile designator expresses
-a URI that denotes an externally defined TTML Profile Definition Document.
-However, it is not required that a conformant TTML content processor be able
-to dereference such an externally specified profile definition.</p>
-<p>In contrast, it is intended that the <el>ttp:profile</el> element be
-used when the author wishes to make use of a modified predefined profile or
-wishes to include in the document instance a non-standard profile definition
-not based upon one of the predefined profiles.</p>
-<p>A predefined profile is supersetted by specifying some feature or extension to
-be required (mandatory) that was either not specified in the underlying, baseline
-profile or was specified as optional (voluntary) in the baseline profile.
-A predefined profile is subsetted by specifying some feature or extension to
-be optional (voluntary) that was specified as required in the underlying, baseline
-profile.</p>
-<p>When a baseline profile is modified by subsetting, the resulting, derived profile
-is referred to as a <emph>subtractive</emph> profile; when modified by supersetting, the result
-is referred to as an <emph>additive</emph> profile.
-It is also possible to define a derived profile that is simultaneously subtractive
-and additive.</p>
-</note>
-<p>If a TTML document instance makes use of a feature defined by
-<specref ref="feature-designations"/> and if the intended use of the
-document requires the recognition and processing of that feature, then
-the document must include a <emph>required feature</emph> or
-a <emph>used feature</emph>
-specification in one of its declared or
-referenced profiles.  If a TTML document instance makes use
-of an extension designatable by <specref
-ref="extension-designations"/> and if the intended use of the document
-requires the recognition and processing of that extension, then the
-document must include a <emph>required extension</emph> or
-a <emph>used extension</emph> specification
-in one of its declared or referenced
-profiles.</p>
-<note role="elaboration">
-<p>A required or used feature
-specification is expressed directly (or indirectly by referring to a
-profile) by means of a <loc
-href="#parameter-vocabulary-feature"><el>ttp:feature</el></loc>
-element where the value of its <att>value</att> attribute is
-<code>required</code> or <code>use</code>,
-respectively.  A required or used
-extension specification is expressed directly (or indirectly by
-referring to a profile) by means of a <loc
-href="#parameter-vocabulary-extension"><el>ttp:extension</el></loc>
-element where the value of its <att>value</att> attribute is
-<code>required</code> or <code>use</code>,
-respectively.</p>
-</note>
-<p>An example of an author defined
-additive, derived profile of the DFXP Presentation
-profile is shown
-below in <specref ref="dfxp-example-sub-profile"/>.</p>
-<table id="dfxp-example-sub-profile" role="example">
-<caption>Example Fragment &ndash; DFXP Additive Profile</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;tt xml:lang="" xmlns="http://www.w3.org/ns/ttml"&gt;
- &lt;head&gt;
-   &lt;profile use="dfxp-presentation" xmlns="http://www.w3.org/ns/ttml#parameter"&gt;
-     &lt;features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
-       &lt;feature value="required"&gt;#fontStyle-italic&lt;/feature&gt;
-     &lt;/features&gt;
-   &lt;/profile&gt;
- &lt;/head&gt;
- &lt;body/&gt;
-&lt;/tt&gt;
-</eg>
-</td></tr>
-</tbody>
-</table>
-<note role="explanation">
-<p>In the above example, the baseline profile is declared to be
-the DFXP Presentation profile, which is then additively modified by making the
-<code>#fontStyle-italic</code> feature required (rather than
-optional as it is defined
-in <specref ref="profile-dfxp-presentation"/>). Note also the resetting of the
-default XMLNS binding on the <el>profile</el> element to the TT Parameter Namespace.</p>
-</note>
-</div2>
-<div2 id="vocabulary-overview">
-<head>Catalog</head>
-<p>The vocabulary of the Timed Text Markup Language (TTML) is
-defined in the following major catalogs (divisions of vocabulary):</p>
-<ulist>
-<item><p><specref ref="core-vocabulary-overview"/></p></item>
-<item><p><specref ref="extension-vocabulary-overview"/></p></item>
-</ulist>
-<p>The core catalog defines the baseline, core vocabulary of TTML,
-and, in particular, the vocabulary of DFXP. The extension catalog
-serves as a placeholder for extensions to the core vocabulary defined
-by TTML.</p>
-<div3 id="core-vocabulary-overview">
-<head>Core Catalog</head>
-<p>The core vocabulary catalog is intended to satisfy the needs of
-TTML while providing a baseline vocabulary for future profiles. This vocabulary
-is divided into distinct categories, specified in detail
-in the following sections:</p>
-<ulist>
-<item><p><specref ref="parameters"/></p></item>
-<item><p><specref ref="content"/></p></item>
-<item><p><specref ref="styling"/></p></item>
-<item><p><specref ref="layout"/></p></item>
-<item><p><specref ref="timing"/></p></item>
-<item><p><specref ref="animation"/></p></item>
-<item><p><specref ref="metadata"/></p></item>
-</ulist>
-<p>The core element vocabulary specified for use with a TTML document
-instance is enumerated in
-<specref ref="element-vocab-table"/>.</p>
-<table id="element-vocab-table" role="common">
-<caption>Table 3 &ndash; Element Vocabulary</caption>
-<col width="25%"/>
-<tbody>
-<tr>
-<th>Module</th>
-<th>Elements</th>
-</tr>
-<tr>
-<td>
-Animation
-</td>
-<td>
-<loc href="#animation-vocabulary-set">set</loc>
-</td>
-</tr>
-<tr>
-<td>
-Content
-</td>
-<td>
-<loc href="#document-structure-vocabulary-body">body</loc>,
-<loc href="#content-vocabulary-div">div</loc>,
-<loc href="#content-vocabulary-p">p</loc>,
-<loc href="#content-vocabulary-span">span</loc>,
-<loc href="#content-vocabulary-br">br</loc>
-</td>
-</tr>
-<tr>
-<td>
-Document
-</td>
-<td>
-<loc href="#document-structure-vocabulary-tt">tt</loc>
-</td>
-</tr>
-<tr>
-<td>
-Head
-</td>
-<td>
-<loc href="#document-structure-vocabulary-head">head</loc>
-</td>
-</tr>
-<tr>
-<td>
-Layout
-</td>
-<td>
-<loc href="#layout-vocabulary-layout">layout</loc>,
-<loc href="#layout-vocabulary-region">region</loc>
-</td>
-</tr>
-<tr>
-<td>
-Metadata
-</td>
-<td>
-<loc href="#metadata-vocabulary-metadata">metadata</loc>
-</td>
-</tr>
-<tr>
-<td>
-Metadata Items
-</td>
-<td>
-<loc href="#metadata-vocabulary-actor">ttm:actor</loc>,
-<loc href="#metadata-vocabulary-agent">ttm:agent</loc>,
-<loc href="#metadata-vocabulary-copyright">ttm:copyright</loc>,
-<loc href="#metadata-vocabulary-desc">ttm:desc</loc>,
-<loc href="#metadata-vocabulary-name">ttm:name</loc>,
-<loc href="#metadata-vocabulary-title">ttm:title</loc>
-</td>
-</tr>
-<tr>
-<td>Parameter Items</td>
-<td><loc href="#parameter-vocabulary-profile">ttp:profile</loc>,
-<loc href="#parameter-vocabulary-features">ttp:features</loc>,
-<loc href="#parameter-vocabulary-feature">ttp:feature</loc>,
-<loc href="#parameter-vocabulary-extensions">ttp:extensions</loc>,
-<loc href="#parameter-vocabulary-extension">ttp:extension</loc>
-</td>
-</tr>
-<tr>
-<td>
-Styling
-</td>
-<td>
-<loc href="#styling-vocabulary-styling">styling</loc>,
-<loc href="#styling-vocabulary-style">style</loc>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<p>Element vocabulary groups that are used in defining content models
-for TTML element types are enumerated in <specref ref="element-vocab-group-table"/>.</p>
-<table id="element-vocab-group-table" role="common">
-<caption>Table 4 &ndash; Element Vocabulary Groups</caption>
-<col width="25%"/>
-<tbody>
-<tr>
-<th>Group</th>
-<th>Elements</th>
-</tr>
-<tr>
-<td>
-Animation.class
-</td>
-<td>
-<loc href="#animation-vocabulary-set">set</loc>
-</td>
-</tr>
-<tr>
-<td>
-Block.class
-</td>
-<td>
-<loc href="#content-vocabulary-div">div</loc> |
-<loc href="#content-vocabulary-p">p</loc>
-</td>
-</tr>
-<tr>
-<td>
-Inline.class
-</td>
-<td>
-<loc href="#content-vocabulary-span">span</loc> |
-<loc href="#content-vocabulary-span">br</loc> |
-<code>#PCDATA</code>
-</td>
-</tr>
-<tr>
-<td>
-Metadata.class
-</td>
-<td>
-<loc href="#metadata-vocabulary-metadata">metadata</loc> |
-<loc href="#metadata-vocabulary-copyright">ttm:agent</loc> |
-<loc href="#metadata-vocabulary-copyright">ttm:copyright</loc> |
-<loc href="#metadata-vocabulary-desc">ttm:desc</loc> |
-<loc href="#metadata-vocabulary-title">ttm:title</loc>
-</td>
-</tr>
-<tr>
-<td>Parameters.class</td>
-<td><loc
-href="#parameter-vocabulary-profile">ttp:profile</loc></td>
-</tr>
-</tbody>
-</table>
-<p/>
-<p>The attribute vocabulary specified for use with the core vocabulary
-catalog is enumerated in
-<specref ref="attribute-vocab-table"/>.</p>
-<table id="attribute-vocab-table" role="common">
-<caption>Table 5 &ndash; Attribute Vocabulary</caption>
-<col width="25%"/>
-<tbody>
-<tr>
-<th>Module</th>
-<th>Attributes</th>
-</tr>
-<tr>
-<td>
-Core Attributes
-</td>
-<td>
-<loc href="#content-attribute-id">xml:id</loc>,
-<loc href="#content-attribute-lang">xml:lang</loc>,
-<loc href="#content-attribute-space">xml:space</loc>
-</td>
-</tr>
-<tr>
-<td>
-Layout
-</td>
-<td>
-<loc href="#layout-attribute-region">region</loc>
-</td>
-</tr>
-<tr>
-<td>
-Metadata Attributes
-</td>
-<td>
-<loc href="#metadata-attribute-agent">ttm:agent</loc>,
-<loc href="#metadata-attribute-role">ttm:role</loc>
-</td>
-</tr>
-<tr>
-<td>
-Parameter Attributes
-</td>
-<td>
-<loc href="#parameter-attribute-cellResolution">ttp:cellResolution</loc>,
-<loc href="#parameter-attribute-clockMode">ttp:clockMode</loc>,
-<loc href="#parameter-attribute-dropMode">ttp:dropMode</loc>,
-<loc href="#parameter-attribute-frameRate">ttp:frameRate</loc>,
-<loc href="#parameter-attribute-frameRateMultiplier">ttp:frameRateMultipler</loc>,
-<loc href="#parameter-attribute-markerMode">ttp:markerMode</loc>,
-<loc href="#parameter-attribute-pixelAspectRatio">ttp:pixelAspectRatio</loc>,
-<loc href="#parameter-attribute-profile">ttp:profile</loc>,
-<loc href="#parameter-attribute-subFrameRate">ttp:subFrameRate</loc>,
-<loc href="#parameter-attribute-tickRate">ttp:tickRate</loc>,
-<loc href="#parameter-attribute-timeBase">ttp:timeBase</loc>
-</td>
-</tr>
-<tr>
-<td>
-Styling
-</td>
-<td>
-<loc href="#style-attribute-style">style</loc>
-</td>
-</tr>
-<tr>
-<td>
-Styling Attributes
-</td>
-<td>
-<loc href="#style-attribute-backgroundColor">tts:backgroundColor</loc>,
-<loc href="#style-attribute-color">tts:color</loc>,
-<loc href="#style-attribute-direction">tts:direction</loc>,
-<loc href="#style-attribute-display">tts:display</loc>,
-<loc href="#style-attribute-displayAlign">tts:displayAlign</loc>,
-<loc href="#style-attribute-extent">tts:extent</loc>,
-<loc href="#style-attribute-fontFamily">tts:fontFamily</loc>,
-<loc href="#style-attribute-fontSize">tts:fontSize</loc>,
-<loc href="#style-attribute-fontStyle">tts:fontStyle</loc>,
-<loc href="#style-attribute-fontWeight">tts:fontWeight</loc>,
-<loc href="#style-attribute-lineHeight">tts:lineHeight</loc>,
-<loc href="#style-attribute-opacity">tts:opacity</loc>,
-<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-showBackground">tts:showBackground</loc>,
-<loc href="#style-attribute-textAlign">tts:textAlign</loc>,
-<loc href="#style-attribute-textDecoration">tts:textDecoration</loc>,
-<loc href="#style-attribute-textOutline">tts:textOutline</loc>,
-<loc href="#style-attribute-unicodeBidi">tts:unicodeBidi</loc>,
-<loc href="#style-attribute-visibility">tts:visibility</loc>,
-<loc href="#style-attribute-wrapOption">tts:wrapOption</loc>,
-<loc href="#style-attribute-writingMode">tts:writingMode</loc>,
-<loc href="#style-attribute-zIndex">tts:zIndex</loc>
-</td>
-</tr>
-<tr>
-<td>
-Timing Attributes
-</td>
-<td>
-<loc href="#timing-attribute-begin">begin</loc>,
-<loc href="#timing-attribute-dur">dur</loc>,
-<loc href="#timing-attribute-end">end</loc>,
-<loc href="#timing-attribute-timeContainer">timeContainer</loc>
-</td>
-</tr>
-</tbody>
-</table>
-<note role="explanation">
-<p>Only those attributes defined as either (1) global, i.e., namespace qualified, or
-(2) shared element-specific, i.e., not namespace qualified but shared across multiple
-element types, are listed in <specref ref="attribute-vocab-table"/> above.
-</p>
-</note>
-<note role="explanation">
-<p>All vocabulary defined by TTML consistently makes use of
-the so-called <emph>lowerCamelCase</emph> naming convention. In some cases, this results in the
-change of a name when the name was based upon another specification
-that used a different naming convention.</p>
-</note>
-</div3>
-<div3 id="extension-vocabulary-overview">
-<head>Extension Catalog</head>
-<p>The extension vocabulary catalog is intended for use by future
-profiles of TTML, and is not further defined
-by this version of this specification.</p>
-<p>In addition to standardized extension vocabulary, a conforming TTML
-document instance may contain arbitrary namespace qualified
-elements that reside in any namespace other than those namespaces
-defined for use with this specification. Furthermore, a conforming TTML
-document instance may contain arbitrary namespace qualified
-attributes on TTML defined vocabulary where such attributes reside in
-any namespace other than those defined for use with this
-specification.</p>
-</div3>
-</div2>
-</div1>
-<div1 id="parameters">
-<head>Parameters</head>
-<p>This section specifies the <emph>parameters</emph> matter of the
-core vocabulary catalog, where
-parameters are to be understood as information that is either (1)
-essential or (2) of significant importance for the purpose of
-interpreting the semantics of other types of information expressed by
-core vocabulary items or for establishing a processing context by means
-of which TTML content can be related to an external environment.</p>
-<div2 id="parameter-element-vocabulary">
-<head>Parameter Element Vocabulary</head>
-<p>The following elements, all defined in the TT Parameter
-Namespace, specify parametric information that applies to a document
-or a content processor:</p>
-<ulist>
-<item><p><specref ref="parameter-vocabulary-profile"/></p></item>
-<item><p><specref ref="parameter-vocabulary-features"/></p></item>
-<item><p><specref ref="parameter-vocabulary-feature"/></p></item>
-<item><p><specref ref="parameter-vocabulary-extensions"/></p></item>
-<item><p><specref ref="parameter-vocabulary-extension"/></p></item>
-</ulist>
-<div3 id="parameter-vocabulary-profile">
-<head>ttp:profile</head>
-<p>The <el>ttp:profile</el> element is used to specify a collection of
-used (mandatory and enabled), required (mandatory),
-and optional (voluntary) features and extensions that must or
-may be supported by a TTML content processor in order to process a TTML
-document that makes use (or may make use) of such features and
-extensions.</p>
-<note role="clarification">
-<p>The difference between a <emph>feature</emph> and an
-<emph>extension</emph> is where it is defined and how it is labeled:
-if defined in this specification (or a future revision thereof) and
-labeled with a feature designation in <specref ref="features"/>, then
-it is considered to be a feature; if defined in another specification
-and labeled there with an extension designation, then it is considered
-to be an extension. In general, features are expected to be defined by
-the W3C standards process, while extensions are expected to be defined by
-third parties.</p>
-</note>
-<p>This specification defines two distinct uses of the <el>ttp:profile</el> element:</p>
-<ulist>
-<item>
-<p>as a child of the <el>head</el> element within a TTML document
-instance;</p>
-</item>
-<item>
-<p>as the root element of a TTML Profile Definition document
-instance;</p>
-</item>
-</ulist>
-<p>When a <el>tt:profile</el> element appears within a TTML document
-instance, its purpose is to express authorial intentions about which
-features and extensions must or may be supported by a recipient
-content processor. In addition, the element indirectly expresses
-information about the set of features or extensions that are (or may
-expected to be) used by the document instance.</p>
-<p>When a <el>tt:profile</el> element is used by a TTML
-Profile Definition document instance, it serves to publish a machine
-readable specification of a specific TTML content profile, of which
-this specification defines four such Profile Definition Documents in
-<specref ref="profiles"/>.</p>
-<p>The <el>ttp:profile</el> element accepts as its children zero or more
-elements in the <code>Metadata.class</code> element group, followed by
-zero or more <el>ttp:features</el> elements, followed by
-zero or more <el>ttp:extensions</el> elements.</p>
-<table id="elt-syntax-parameter-profile" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: ttp:profile</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;ttp:profile
-  use = string
-  <loc href="#content-attribute-id">xml:id</loc> = ID
-  {<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="#parameter-vocabulary-features">ttp:features</loc>*, <loc href="#parameter-vocabulary-extensions">ttp:extensions</loc>*
-&lt;/ttp:profile&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If specified, the <att>use</att> attribute must adhere to the
-<code>xsd:anyURI</code> data type defined by <bibref ref="xsd-2"/>,
-&sect;3.2.17, and, furthermore, must denote a profile designator in
-accordance with <specref ref="vocabulary-profiles"/>. In this case,
-the profile designator must refer to (1) a standard, predefined
-TTML Profile Definition Document as defined by <specref ref="profiles"/>,
-or (2) a dereferenceable resource representing a valid TTML Profile Definition
-document instance. In either case, the referenced profile serves as the
-baseline profile of the specifying <el>ttp:profile</el> element.</p>
-<p>If the <att>use</att> attribute is not specified, then the baseline
-profile of the <el>ttp:profile</el> element must be considered to be
-the empty (null) profile, i.e., a profile definition containing no
-feature or extension specifications.</p>
-<p>The collection of features and extensions of a profile are determined according
-to the following ordered rules:</p>
-<olist>
-<item>
-<p>initialize the features and extensions of the profile to the empty
-set;</p>
-</item>
-<item>
-<p>if a <att>use</att> attribute is present, then augment the profile
-with the set of features and extensions specified by the referenced
-baseline profile;</p>
-</item>
-<item>
-<p>for each <el>ttp:feature</el> and <el>ttp:extension</el> element
-descendant of the <el>ttp:profile</el> element, using a post-order
-traversal, merge the specified feature or extension with the features
-and extensions of the profile, where merging a feature or extension
-entails replacing an existing feature or extension specification, if
-it already exists, or adding a new feature or extension specification,
-if it does not yet exist in the profile;</p>
-</item>
-</olist>
-<p>A conformant TTML processor is not required to be able to
-dereference a TTML Profile Definition Document that is not one of the
-standard, predefined profiles defined by <specref ref="profiles"/>.  A
-conformant TTML processor may make use of a built-in, static
-form of each standard, predefined profile so as not to require
-dereferencing a network resource.</p>
-<p>If a TTML processor is unable to dereference a non-standard TTML
-Profile Definition Document, then it must not further process the
-document without the presence of an explicit override from an end-user
-or some implementation specific parameter traceable to an end-user or
-to a user or system configuration setting. If a TTML processor aborts
-processing of a TTML document instance due to the inability to
-reference a non-standard TTML Profile Definition Document, then some
-end-user notification should be given unless the end-user or system
-has disabled such a notification, or if the processor does not permit
-or entail the intervention of an end-user.</p>
-<p>The <el>ttp:profile</el> element is illustrated by the following example.</p>
-<table id="parameter-vocabulary-profile-example-1" role="example">
-<caption>Example Fragment &ndash; ttp:profile</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;ttp:profile use="dfxp-presentation"&gt;
-  &lt;ttp:features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
-    &lt;ttp:feature&gt;#text-outline&lt;/ttp:feature&gt;
-  &lt;/ttp:features&gt;
-&lt;/ttp:profile&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<note role="explanation">
-<p>In the above example, the DFXP presentation profile is used as the
-baseline profile. This baseline profile is then supersetted (thus
-creating an additive derived profile) by requiring support for
-<code>#text-outline</code> feature.</p>
-</note>
-</div3>
-<div3 id="parameter-vocabulary-features">
-<head>ttp:features</head>
-<p>The <el>ttp:features</el> element is a container element used to group
-infomation about feature support requirements.</p>
-<p>The <el>ttp:features</el> element accepts as its children zero or more
-elements in the <code>Metadata.class</code> element group, followed by
-zero or more <el>ttp:feature</el> elements.</p>
-<table id="elt-syntax-parameter-features" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: ttp:features</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;ttp:features
-  xml:base = string : <emph>TT Feature Namespace</emph>
-  <loc href="#content-attribute-id">xml:id</loc> = ID
-  {<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="#parameter-vocabulary-feature">ttp:feature</loc>*
-&lt;/ttp:features&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If specified, the <att>xml:base</att>
-attribute must (1) adhere to the
-<code>xsd:anyURI</code> data type defined by <bibref ref="xsd-2"/>,
-&sect;3.2.17, (2) express an absolute URI that
-adheres to <bibref ref="xmlbase"/> and,
-(3) express a feature namespace as defined by
-<specref ref="feature-designations"/>. If not specified, the
-<att>xml:base</att> attribute's default
-value applies, which is the TT Feature Namespace.</p>
-<p>The <att>xml:base</att> attribute is
-used to permit the abbreviation of feature designation URIs expressed
-by child <el>ttp:feature</el> elements.</p>
-</div3>
-<div3 id="parameter-vocabulary-feature">
-<head>ttp:feature</head>
-<p>The <el>ttp:feature</el> element is used to specify
-infomation about support requirements for a particular feature.</p>
-<p>The children of the <el>ttp:feature</el> element must express a non-empty
-sequence of character information items that adheres to the
-<code>xsd:anyURI</code> data type defined by <bibref ref="xsd-2"/>,
-&sect;3.2.17.</p>
-<table id="elt-syntax-parameter-feature" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: ttp:feature</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;ttp:feature
-  value = (optional|required|use) : required
-  <loc href="#content-attribute-id">xml:id</loc> = ID
-  {<emph>any attribute not in default or any TT namespace</emph>}&gt;
-  <emph>Content:</emph> #PCDATA
-&lt;/ttp:feature&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If the URI expressed by the content of the <el>ttp:feature</el>
-element is a relative URI, then, when combined with the
-feature namespace value expressed by the
-<att>xml:base</att> attribute of the
-nearest ancestor <el>ttp:features</el> element, it must express an
-absolute URI.  In either case (original absolute URI or resulting
-absolutized URI), the URI expressed by the <el>ttp:feature</el>
-element must further adhere to the syntax of a feature designation as
-defined by <specref ref="feature-designations"/>.</p> <p>If
-the URI expressed by the content of the <el>ttp:feature</el> element
-is a relative URI, then an <att>xml:base</att> attribute should be
-specified on the nearest ancestor <el>ttp:features</el> element.</p>
-<p>The <att>value</att> attribute specifies whether a conforming TTML
-processor must or may implement the designated feature in order to
-process the document. If the value of the <att>value</att> attribute
-is <code>optional</code>, then the processor need
-not implement or otherwise support the feature in order to process the
-document; if the value is <code>required</code>, then the processor
-must implement or otherwise support the feature in order to process
-the document; if the value is
-<code>use</code>, then the processor must both (1) implement or
-otherwise support the feature and (2) enable (activate) use of the
-feature.</p>
-
-<note role="clarification">
-<p>The default value of the <att>value</att> attribute is
-<code>required</code>, as indicated in the above element information
-item definition. Therefore, if a <att>value</att> attribute is not
-specified on a <el>ttp:feature</el> element, it is equivalent to
-specifying that support for the feature is required.</p>
-</note>
-<p>If the value of the <att>value</att> attribute is
-<code>required</code> or <code>use</code>,
-and if the TTML processor implementation does
-not support the feature, then it must not further process the document
-without the presence of an explicit override from an end-user or some
-implementation specific parameter traceable to an end-user or to a
-user or system configuration setting.  If a TTML processor aborts
-processing of a TTML document instance due to the specification of a
-required, but unsupported feature by this element, then some end-user
-notification should be given unless the end-user or system has
-disabled such a notification, or if the processor does not permit or
-entail the intervention of an end-user.</p>
-<p>If the value of the <att>value</att> attribute is
-<code>optional</code>, and if the TTML processor implementation does
-not support the feature, then it may further process the document even
-in the case that some use of the feature is present in the document.
-In the case of actual use of a feature designated as optional, the
-default semantics associated with that feature apply; that is, the
-processor may behave as if the feature were not actually used or
-referenced by the document. Notwithstanding the above, the syntactic
-presence or reference to an optional feature by a document must not be
-considered to be a violation of document validity or a barrier to
-further processing if the syntactic expression is well-formed and
-valid.</p>
-<p>The <el>ttp:feature</el> element is illustrated by the following example.</p>
-<table id="parameter-vocabulary-feature-example-1" role="example">
-<caption>Example Fragment &ndash; ttp:feature</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;ttp:profile use="http://www.w3.org/ns/ttml/profile/dfxp-presentation"&gt;
-  &lt;ttp:features xml:base="http://www.w3.org/ns/ttml/feature/"&gt;
-    <phrase role="strong">&lt;ttp:feature value="required"&gt;#fontStyle-italic&lt;/ttp:feature&gt;</phrase>
-    <phrase role="strong">&lt;ttp:feature value="required"&gt;#textDecoration-under&lt;/ttp:feature&gt;</phrase>
-  &lt;/ttp:features&gt;
-&lt;/ttp:profile&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<note role="explanation">
-<p>In the above example, the DFXP presentation profile is used as the
-baseline profile. This baseline profile is then modified by two
-<el>ttp:feature</el> elements in order to
-superset the baseline profile (since neither
-<code>#fontStyle-italic</code> nor <code>#textDecoration-under</code>
-are required by the DFXP presentation profile).  
-<!-- removed text:
-Note that
-the explicit specification of <code>required</code> on the
-<att>value</att> attribute on these two
-<el>ttp:feature</el> elements is not strictly
-necessary, since it is the default value of this
-attribute.--></p> 
-<p>The effect of this example is to express authorial intentions that
-italic font style and text underlining must be
-supported.</p>
-</note>
-</div3>
-<div3 id="parameter-vocabulary-extensions">
-<head>ttp:extensions</head>
-<p>The <el>ttp:extensions</el> element is a container element used to group
-infomation about extension support requirements.</p>
-<p>The <el>ttp:extensions</el> element accepts as its children zero or more
-elements in the <code>Metadata.class</code> element group, followed by
-zero or more <el>ttp:extension</el> elements.</p>
-<table id="elt-syntax-parameter-extensions" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: ttp:extensions</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;ttp:extensions
-  xml:base = string : <emph>TT Extension Namespace</emph>
-  <loc href="#content-attribute-id">xml:id</loc> = ID
-  {<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="#parameter-vocabulary-extension">ttp:extension</loc>*
-&lt;/ttp:extensions&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If specified, the <att>xml:base</att>
-attribute must (1) adhere to the
-<code>xsd:anyURI</code> data type defined by <bibref ref="xsd-2"/>,
-&sect;3.2.17, (2) express an absolute URI that
-adheres to <bibref ref="xmlbase"/> and,
-(3) express an extension namespace as defined by
-<specref ref="extension-designations"/>. If not specified, the
-<att>xml:base</att> attribute's default
-value applies, which is the TT Extension Namespace.</p>
-<p>The <att>xml:base</att> attribute is
-used to permit the abbreviation of feature designation URIs expressed
-by child <el>ttp:extension</el> elements.</p>
-</div3>
-<div3 id="parameter-vocabulary-extension">
-<head>ttp:extension</head>
-<p>The <el>ttp:extension</el> element is used to specify
-infomation about support requirements for a particular extension.</p>
-<p>The children of the <el>ttp:extension</el> element must express a non-empty
-sequence of character information items that adheres to the
-<code>xsd:anyURI</code> data type defined by <bibref ref="xsd-2"/>,
-&sect;3.2.17.</p>
-<table id="elt-syntax-parameter-extension" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: ttp:extension</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;ttp:extension
-  value = (optional|required|use) : required
-  <loc href="#content-attribute-id">xml:id</loc> = ID
-  {<emph>any attribute not in default or any TT namespace</emph>}&gt;
-  <emph>Content:</emph> #PCDATA
-&lt;/ttp:extension&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If the URI expressed by the content of the <el>ttp:extension</el>
-element is a relative URI, then, when combined with the
-extension namespace value expressed by the
-<att>xml:base</att> attribute of the
-nearest ancestor <el>ttp:extensions</el> element, it must express an
-absolute URI.  In either case (original absolute URI or resulting
-absolutized URI), the URI expressed by the <el>ttp:extension</el>
-element must further adhere to the syntax of an extension designation
-as defined by <specref ref="extension-designations"/>.</p>
-<p>If the URI expressed by the content of the
-<el>ttp:feature</el> element is a relative URI, then an
-<att>xml:base</att> attribute should be specified on the nearest
-ancestor <el>ttp:extensions</el> element.</p>
-<p>The <att>value</att> attribute specifies whether a conforming TTML
-processor must or may implement the designated extension in order to
-process the document. If the value of the <att>value</att> attribute
-is <code>optional</code>, then the processor need
-not implement or otherwise support the extension in order to process the
-document; if the value is <code>required</code>, then the processor
-must implement or otherwise support the extension in order to process
-the document; if the value is
-<code>use</code>, then the processor must both (1) implement or
-otherwise support the extension and (2) enable (activate) use of the
-extension.</p>
-<note role="clarification">
-<p>The default value of the <att>value</att> attribute is
-<code>required</code>, as indicated in the above element information
-item definition. Therefore, if a <att>value</att> attribute is not
-specified on a <el>ttp:extension</el> element, it is equivalent to
-specifying that support for the extension is required.</p>
-</note>
-<p>If the value of the <att>value</att> attribute is
-<code>required</code> or <code>use</code>,
-and if the TTML processor implementation does not support the
-extension, then it must not further process the document without the
-presence of an explicit override from an end-user or some
-implementation specific parameter traceable to an end-user or to a
-user or system configuration setting.  If a TTML processor aborts
-processing of a TTML document instance due to the specification of a
-required, but unsupported extension by this element, then some
-end-user notification should be given unless the end-user or system
-has disabled such a notification, or if the processor does not permit
-or entail the intervention of an end-user.</p>
-<p>If the value of the <att>value</att> attribute is
-<code>optional</code>, and if the TTML processor implementation does
-not support the extension, then it may further process the document even
-in the case that some use of the extension is present in the document.
-In the case of actual use of an extension designated as optional, the
-default semantics associated with that extension apply; that is, the
-processor may behave as if the extension were not actually used or
-referenced by the document. Notwithstanding the above, the syntactic
-presence or reference to an optional extension by a document must not be
-considered to be a violation of document validity or a barrier to
-further processing if the syntactic expression is well-formed and
-valid.</p>
-<p>The <el>ttp:extension</el> element is illustrated by the following example.</p>
-<table id="parameter-vocabulary-extension-example-1" role="example">
-<caption>Example Fragment &ndash; ttp:extension</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;ttp:profile use="http://www.w3.org/ns/ttml/profile/dfxp-transformation"&gt;
-  &lt;ttp:extensions xml:base="http://foo.bar.example.org/ttaf1/extension/"&gt;
-    <phrase role="strong">&lt;ttp:extension value="use"&gt;#prefilter-by-language&lt;/ttp:extension&gt;</phrase>
-  &lt;/ttp:extensions&gt;
-&lt;/ttp:profile&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<note role="explanation">
-<p>In the above example, the DFXP transformation profile is used as
-the baseline profile. This baseline profile is then supersetted by
-specifying that support and use is required for a private extension
-defined in a third party namespace.</p>
-<p>The effect of this example is to express authorial intentions that
-a recipient processor must support the DFXP transformation profile and
-must also support and use an extension defined by a third party.</p>
-</note>
-</div3>
-</div2>
-<div2 id="parameter-attribute-vocabulary">
-<head>Parameter Attribute Vocabulary</head>
-<p>The following attributes are defined in the TT Parameter Namespace.</p>
-<ulist>
-<item><p><specref ref="parameter-attribute-cellResolution"/></p></item>
-<item><p><specref ref="parameter-attribute-clockMode"/></p></item>
-<item><p><specref ref="parameter-attribute-dropMode"/></p></item>
-<item><p><specref ref="parameter-attribute-frameRate"/></p></item>
-<item><p><specref ref="parameter-attribute-frameRateMultiplier"/></p></item>
-<item><p><specref ref="parameter-attribute-markerMode"/></p></item>
-<item><p><specref ref="parameter-attribute-pixelAspectRatio"/></p></item>
-<item><p><specref ref="parameter-attribute-profile"/></p></item>
-<item><p><specref ref="parameter-attribute-subFrameRate"/></p></item>
-<item><p><specref ref="parameter-attribute-tickRate"/></p></item>
-<item><p><specref ref="parameter-attribute-timeBase"/></p></item>
-</ulist>
-<p>Unless explicitly stated otherwise, linear white-space (LWSP) may
-appear between tokens of a value of a TT Parameter.</p>
-<div3 id="parameter-attribute-cellResolution">
-<head>ttp:cellResolution</head>
-<p>The <att>ttp:cellResolution</att> attribute may be used by an author
-to express the number of horizontal and vertical cells into which the root container region
-area is divided for the purpose of expressing presentation semantics in terms of
-a uniform grid.</p>
-<p>If specified, the value of this attribute must adhere to the following syntax:</p>
-<table id="parameter-attribute-cellResolution-syntax" role="syntax">
-<caption>Syntax Representation &ndash; ttp:cellResolution</caption>
-<tbody>
-<tr>
-<td>
-<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>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If not specified, the number of columns and rows must be considered
-to be 32 and 15, respectively. If specified, then columns or rows must not be zero (0).</p>
-<note role="motivation">
-<p>The choice of values 32 and 15 are based on this being the
-maximum number of columns and rows defined by <bibref
-ref="cea608c"/>.</p>
-</note>
-<p>A <att>ttp:cellResolution</att> attribute is considered to be significant only
-when specified on the <el>tt</el> element.</p>
-<note role="explanation">
-<p>The use of a uniform grid is employed only for the purpose of
-measuring lengths and expressing coordinates. In particular, it is not
-assumed that the presentation of text or the alignment of individual
-glyph areas is
-coordinated with this grid. Such alignment is possible, but
-requires the use of a monospaced font and a font size whose EM square exactly
-matches the cell size.</p>
-</note>
-</div3>
-<div3 id="parameter-attribute-clockMode">
-<head>ttp:clockMode</head>
-<p>The <att>ttp:clockMode</att> 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 <specref
-ref="parameter-attribute-timeBase"/>.</p>
-<note role="explanation">
-<p>See <specref ref="timing-time-value-expressions"/> for the
-specification of time expression syntax.</p>
-</note>
-<p>If specified, the value of this attribute must adhere to the following syntax:</p>
-<table id="parameter-attribute-clockMode-syntax" role="syntax">
-<caption>Syntax Representation &ndash; ttp:clockMode</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-ttp:clockMode
-  : "local"
-  | "gps"
-  | "utc"
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If the time base, defined by <specref
-ref="parameter-attribute-timeBase"/>, 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;
-if <code>utc</code>, then time expressions are
-interpreted as UTC time coordinates
-<bibref ref="utc"/>;
-if <code>gps</code>, then time expressions are
-interpreted as GPS time coordinates
-<bibref ref="gps"/>.</p>
-<note role="explanation">
-<p>The primary difference between GPS time and UTC time is that GPS
-time is not adjusted for leap seconds, while UTC time is adjusted as
-follows: UTC = TAI (<emph>Temp Atomique International</emph>) + <emph>leap seconds
-accumulated since 1972</emph>. TAI is maintained by the <emph>Bureau
-International des Poids et Mesures</emph> (BIPM) in Sevres, France.
-The GPS system time is steered to a Master Clock (MC) at the US Naval
-Observatory which is kept within a close but unspecified
-tolerance of TAI.</p>
-</note>
-<p>If not specified, the value of this parameter must be considered
-to be <code>utc</code>.</p>
-<p>A <att>ttp:clockMode</att> attribute is considered to be significant only
-when specified on the <el>tt</el> element.</p>
-</div3>
-<div3 id="parameter-attribute-dropMode">
-<head>ttp:dropMode</head>
-<p>The <att>ttp:dropMode</att> attribute is used to specify
-constraints on the interpretation and use of frame counts
-that correspond with <bibref ref="smpte12m"/> time coordinates when operating
-with time base of <code>smpte</code> as defined by
-<specref ref="parameter-attribute-timeBase"/>.</p>
-<p>If specified, the value of this attribute must adhere to the following syntax:</p>
-<table id="parameter-attribute-dropMode-syntax" role="syntax">
-<caption>Syntax Representation &ndash; ttp:dropMode</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-ttp:dropMode
-  : "dropNTSC"
-  | "dropPAL"
-  | "nonDrop"
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If the time base, defined by <specref
-ref="parameter-attribute-timeBase"/>, 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
-<emph>N&minus;1</emph>, where <emph>N</emph> is the value specified by
-the <att>ttp:frameRate</att> parameter, but while ignoring any value
-specified by the <att>ttp:frameRateMultiplier</att> parameter.</p>
-<note role="clarification"> <p>When operating in <code>nonDrop</code>
-mode, a second of a time expression may or may not be equal to a
-second of real time during normal (1x speed) forward playback. If the
-<att>ttp:frameRateMultiplier</att> parameter is specified and is not
-equal to 1:1, then a second of a time expression will either be
-shorter or longer than a second of elapsed play in real
-time.</p></note>
-<p>If this parameter's value is <code>dropNTSC</code>, then, within any
-given second of a time expression except the second <code>00</code>,
-frames count from 0 to <emph>N&minus;1</emph>, where <emph>N</emph> is
-the value specified by the <att>ttp:frameRate</att> parameter, but
-while ignoring any value specified by the
-<att>ttp:frameRateMultiplier</att> parameter. If the second of a time
-expression is <code>00</code> and the minute of the time expression is
-not <code>00</code>, <code>10</code>, <code>20</code>, <code>30</code>,
-<code>40</code>, or <code>50</code>, then frame codes <code>00</code>
-and <code>01</code> are dropped during that second; otherwise, these
-frame codes are not dropped.</p>
-<note role="example"> <p>For example, when operating in <code>dropNTSC</code>
-mode with <att>ttp:frameRate</att> of <code>30</code>, a discontinuity
-in frame count occurs between consecutive frames as shown in the
-following sequence of time expressions: <code>01:08:59:28</code>,
-<code>01:08:59:29</code>, <code>01:09:00:02</code>,
-<code>01:09:00:03</code>.</p></note>
-<p>If this parameter's value is <code>dropPAL</code>, then, within any
-given second of a time expression except the second <code>00</code>,
-frames count from 0 to <emph>N&minus;1</emph>, where <emph>N</emph> is
-the value specified by the <att>ttp:frameRate</att> parameter, but
-while ignoring any value specified by the
-<att>ttp:frameRateMultiplier</att> parameter. If the second of a time
-expression is <code>00</code> and the minute of the time expression is
-even but not <code>00</code>, <code>20</code>, or <code>40</code>,
-then frame codes <code>00</code> through <code>03</code> are dropped
-during that second; otherwise, these frame codes are not dropped.</p>
-<note role="example"><p>For example, when operating in <code>dropPAL</code>
-mode with <att>ttp:frameRate</att> of <code>30</code>, a discontinuity
-in frame count occurs between consecutive frames as shown in the
-following sequence of time expressions: <code>01:09:59:28</code>,
-<code>01:09:59:29</code>, <code>01:10:00:04</code>,
-<code>01:10:00:04</code>.</p></note>
-<note role="explanation">
-<p>The <code>dropPAL</code> mode is also known as the
-<emph>M/PAL</emph> or <emph>PAL (M)</emph> drop-frame
-code, which uses PAL modulation with the NTSC frame rate of ~29.97
-frames/second. The M/PAL system is used primarily in Brazil.</p>
-</note>
-<p>If not specified, then <code>nonDrop</code> must be assumed to apply.</p>
-<p>A <att>ttp:dropMode</att> attribute is considered to be significant only
-when specified on the <el>tt</el> element.</p>
-</div3>
-<div3 id="parameter-attribute-frameRate">
-<head>ttp:frameRate</head>
-<p>The <att>ttp:frameRate</att> attribute is used to specify the frame rate of a related
-media object or the intrinsic frame rate of a document instance in case it is intended
-to function as an independent media object.</p>
-<p>If specified, the value of this attribute must adhere to the following syntax:</p>
-<table id="parameter-attribute-frameRate-syntax" role="syntax">
-<caption>Syntax Representation &ndash; ttp:frameRate</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-ttp:frameRate
-  : <loc href="#style-value-digit">&lt;digit&gt;</loc>+                                // <emph>value</emph> > 0
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>The frame rate that applies to a document instance is used to
-interpret time expressions that are expressed in <emph>frames</emph>
-as defined by <specref ref="timing-value-timeExpression"/>.</p>
-<p>A frame is interpreted as a division of a second of media
-time, such that if the frame rate is specified as <emph>F</emph>, then
-a second of media time is divided into <emph>F</emph> intervals of
-equal duration, where each interval is labeled as frame <emph>f</emph>,
-with <emph>f</emph> &isin; [0&hellip;<emph>F&minus;1</emph>].</p>
-<p>If not specified, the frame rate must be considered to be equal to some
-application defined frame rate, or if no application defined frame rate applies,
-then thirty (30) frames per second. If specified, then the frame rate must
-be greater than zero (0).</p>
-<p>A <att>ttp:frameRate</att> attribute is considered to be significant only
-when specified on the <el>tt</el> element.</p>
-</div3>
-<div3 id="parameter-attribute-frameRateMultiplier">
-<head>ttp:frameRateMultiplier</head>
-<p>The <att>ttp:frameRateMultiplier</att> attribute is used to
-specify a multiplier to be applied to the frame rate specified by a
-<att>ttp:frameRate</att> attribute in order to compute the effective
-frame rate.</p>
-<p>If specified, the value of this attribute must adhere to the following syntax:</p>
-<table id="parameter-attribute-frameRateMultiplier-syntax" role="syntax">
-<caption>Syntax Representation &ndash; ttp:frameRateMultiplier</caption>
-<tbody>
-<tr>
-<td>
-<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>
-</td>
-</tr>
-</tbody>
-</table>
-<p>A frame rate multiplier is used when the desired frame rate cannot
-be expressed as an integral number of frames per second.</p>
-<p>If not specified, the frame rate multiplier must be considered to be equal to one (1:1).
-Both numerator and denominator must be non-zero.</p>
-<p>A <att>ttp:frameRateMultiplier</att> attribute is considered to be significant only
-when specified on the <el>tt</el> element.</p>
-<note role="example">
-<p>The frame rate multiplier used for synchronizing with NTSC <bibref
-ref="smpte170m"/>
-formatted video objects at 30 frames per second is nominally
-1000:1001. The nominal frame rate of NTSC video is defined as the chrominance
-sub-carrier frequency of 3,579,545.45&hellip;Hz (= 5.0MHz &mult; 63/88) times the ratio 2/455 divided by
-the number of horizontal lines per frame of 525, which yields a frame
-rate of 29.970029970029&hellip; (= 30 &mult; 1000/1001) frames per
-second. Other frame rate multipliers apply to different regions of
-usage and video format standards.</p>
-</note>
-<note role="example">
-<p>Except in the case of PAL/M, the frame rate multiplier used for synchronizing with PAL
-formatted video objects at 25 frames per second is nominally 1:1.</p>
-</note>
-</div3>
-<div3 id="parameter-attribute-markerMode">
-<head>ttp:markerMode</head>
-<p>The <att>ttp:markerMode</att> attribute is used to specify
-constraints on the interpretation and use of time expressions
-that correspond with <bibref ref="smpte12m"/> time coordinates when operating
-with time base of <code>smpte</code> as defined by
-<specref ref="parameter-attribute-timeBase"/>.</p>
-<p>If specified, the value of this attribute must adhere to the following syntax:</p>
-<table id="parameter-attribute-markerMode-syntax" role="syntax">
-<caption>Syntax Representation &ndash; ttp:markerMode</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-ttp:markerMode
-  : "continuous"
-  | "discontinuous"
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If the time base, defined by <specref
-ref="parameter-attribute-timeBase"/>, is designated as
-<code>smpte</code>, then this parameter applies as follows: if the
-parameter's value is <code>continuous</code>, then <bibref ref="smpte12m"/> time coordinates
-may be assumed to be linear and either monotonically increasing or
-decreasing; however, if <code>discontinuous</code>, then any assumption
-must not be made regarding linearity or monotonicity of time coordinates.</p>
-<p>If not specified, the value of this parameter must be considered
-to be <code>continuous</code>.</p>
-<p>A <att>ttp:markerMode</att> attribute is considered to be significant only
-when specified on the <el>tt</el> element.</p>
-<p>If a value of <code>discontinuous</code> applies, then time
-expressions must not be converted to either media time or real time
-coordinates, arithmetical operators (addition, multiplication) are not
-defined on time expressions, and, consequently, any expression of a
-duration must be considered to be invalid.</p>
-<note role="explanation">
-<p>When operating with <code>smpte</code> time base and
-<code>discontinuous</code> marker mode, there is no effective time coordinate
-space; rather, all time expressions are interpreted as labeled
-synchronization events (markers), where some external synchronization
-context emits these events, which, when they correspond with time
-expressions that denote the same label, cause a temporal interval to
-begin or end accordingly.</p>
-<p>An additional side-effect of operating in <code>discontinuous</code>
-mode is that time expressions of children have no necessary
-relationship with time expressions of their temporal container; that
-is, temporal containers and children of these containers are
-temporally activated and inactivated independently based on the
-occurrence of a labeled synchronization (marker) event.</p>
-</note>
-<note role="explanation">
-<p>The notion of marker discontinuity as captured by this parameter
-is logically independent from the method used to count frames as
-expressed by the <att>ttp:dropMode</att> parameter. In particular,
-even if the <att>ttp:dropMode</att> parameter is specified as
-<code>dropNTSC</code> or <code>dropPAL</code>, the marker mode may be
-specified as <code>continuous</code>, even in the presence of frame count
-discontinuities induced by the frame counting method, unless there
-were some other non-linearity or discontinuity in marker labeling, for
-example, two consecutive frames labeled as <code>10:00:00:00</code>
-and <code>10:00:01:00</code>.
-</p>
-</note>
-</div3>
-<div3 id="parameter-attribute-pixelAspectRatio">
-<head>ttp:pixelAspectRatio</head>
-<p>The <att>ttp:pixelAspectRatio</att> attribute may be used by a content author
-to express the aspect ratio of non-square pixels in the production of content that
-makes use of pixel coordinates.</p>
-<p>If specified, the value of this attribute must adhere to the following syntax:</p>
-<table id="parameter-attribute-pixelAspectRatio-syntax" role="syntax">
-<caption>Syntax Representation &ndash; ttp:pixelAspectRatio</caption>
-<tbody>
-<tr>
-<td>
-<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>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If not specified, then square pixels (i.e., aspect ratio 1:1) must be assumed to apply.
-If specified, then both width and height must be non-zero.</p>
-<p>A <att>ttp:pixelAspectRatio</att> attribute is considered to be significant only
-when specified on the <el>tt</el> element.</p>
-<note role="explanation">
-<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>
-</note>
-</div3>
-<div3 id="parameter-attribute-profile">
-<head>ttp:profile</head>
-<p>The <att>ttp:profile</att> attribute may be used by a content author
-to express the profile of the Timed Text Markup Language (TTML) used
-in a document instance.</p>
-<p>If specified, the value of this attribute must adhere to the
-<code>xsd:anyURI</code> data type defined by <bibref ref="xsd-2"/>,
-&sect;3.2.17, and, further, must specify a
-profile designator in accordance with
-<specref ref="vocabulary-profiles"/>.</p>
-<p>A <att>ttp:profile</att>
-attribute is considered to be significant only when specified on the
-<el>tt</el> element.</p>
-</div3>
-<div3 id="parameter-attribute-subFrameRate">
-<head>ttp:subFrameRate</head>
-<p>The <att>ttp:subFrameRate</att> attribute is used to specify the sub-frame rate of a related
-media object or the intrinsic sub-frame rate of a document instance in case it is intended
-to function as an independent media object.</p>
-<p>If specified, the value of this attribute must adhere to the following syntax:</p>
-<table id="parameter-attribute-subFrameRate-syntax" role="syntax">
-<caption>Syntax Representation &ndash; ttp:subFrameRate</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-ttp:subFrameRate
-  : <loc href="#style-value-digit">&lt;digit&gt;</loc>+                                // <emph>value</emph> > 0
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>The sub-frame rate that applies to a document instance is used to
-interpret time expressions that are expressed in <emph>sub-frames</emph>
-as defined by <specref ref="timing-value-timeExpression"/>.</p>
-<p>A sub-frame is interpreted as a division of a frame of media
-time, such that if the sub-frame rate is specified as <emph>S</emph>, then
-a frame of media time is divided into <emph>S</emph> intervals of
-equal duration, where each interval is labeled as sub-frame <emph>s</emph>,
-with <emph>s</emph> &isin; [0&hellip;<emph>S&minus;1</emph>].</p>
-<p>If not specified, the sub-frame rate must be considered to be
-equal to one (1). If specified, then the sub-frame rate must be greater than zero (0).</p>
-<p>A <att>ttp:subFrameRate</att> attribute is considered to be significant only
-when specified on the <el>tt</el> element.</p>
-<note role="clarification">
-<p>The sub-frame is sometimes referred to as a <emph>field</emph> in
-the context of synchronization with an interlaced video media object.</p>
-</note>
-</div3>
-<div3 id="parameter-attribute-tickRate">
-<head>ttp:tickRate</head>
-<p>The <att>ttp:tickRate</att> attribute is used to specify the tick rate of a related
-media object or the intrinsic tick rate of content of a document instance in case it is intended
-to function as an independent media object.</p>
-<p>If specified, the value of this attribute must adhere to the following syntax:</p>
-<table id="parameter-attribute-tickRate-syntax" role="syntax">
-<caption>Syntax Representation &ndash; ttp:tickRate</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-ttp:tickRate
-  : <loc href="#style-value-digit">&lt;digit&gt;</loc>+                                // <emph>value</emph> > 0
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>The tick rate that applies to a document instance is used to
-interpret time expressions that are expressed in <emph>ticks</emph> by
-using the <code>t</code> metric as defined by <specref
-ref="timing-value-timeExpression"/>.</p>
-<p>A tick is interpreted as an integral division of a second of media
-time, such that if the tick rate is specified as <emph>T</emph>, then
-a second of media time is divided into <emph>T</emph> intervals of
-equal duration, where each interval is labeled as tick <emph>t</emph>,
-with <emph>t</emph> &isin; [0&hellip;<emph>T&minus;1</emph>].</p>
-<p>If not specified, then if a frame rate is specified, the tick rate
-must be considered to be the effective frame rate multiplied by the
-sub-frame rate (i.e., ticks are interpreted as sub-frames); or, if no
-frame rate is specified, the tick rate must be considered to be one (1)
-tick per second of media time. If specified, then the tick rate
-must not be zero (0).</p>
-<note role="clarification">
-<p>There is no predefined relationship between ticks and frames or
-sub-frames. Ticks are an arbitrary division of seconds that permit
-use of fixed point arithmetic rather than fractional (and potentially
-inexact) expressions of seconds.</p>
-</note>
-<p>A <att>ttp:tickRate</att> attribute is considered to be significant only
-when specified on the <el>tt</el> element.</p>
-</div3>
-<div3 id="parameter-attribute-timeBase">
-<head>ttp:timeBase</head>
-<p>The <att>ttp:timeBase</att> attribute is used to specify the
-temporal coordinate system by means of which time expressions are
-interpreted in a document instance.</p>
-<p>If specified, the value of this attribute must adhere to the following syntax:</p>
-<table id="parameter-attribute-timeBase-syntax" role="syntax">
-<caption>Syntax Representation &ndash; ttp:timeBase</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-ttp:timeBase
-  : "media"
-  | "smpte"
-  | "clock"
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If the time base is designated as <code>media</code>, then a time
-expression denotes a coordinate in some media object's time line,
-where the media object may be an external media object with which the
-content of a document instance is to be synchronized, or it may
-be the content of a document instance itself in a case where
-the timed text content is intended to establish an independent time
-line.</p>
-<note role="explanation">
-<p>When using a media time base, if that time base is paused or
-scaled positively or negatively, then it is expected that the
-presentation of associated Timed Text content will be similarly
-paused, accelerated, or decelerated, respectively. The means for
-controlling an external
-media time base is outside the scope of this specification.</p>
-</note>
-<p>If the time base is designated as <code>smpte</code>,
-then a time expression denotes a <bibref ref="smpte12m"/> time
-coordinate with which the content of a document instance is to
-be synchronized.  In this case, the value of the <att>ttp:markerMode</att> 
-and <att>ttp:dropMode</att> parameters apply, as defined by <specref
-ref="parameter-attribute-markerMode"/> and <specref
-ref="parameter-attribute-dropMode"/>, respectively.</p>
-<p>If the time base is designated as <code>clock</code>, then the time
-expression denotes a coordinate in some real-world time line as
-established by some real-time clock, such as the local wall-clock time
-or UTC (Coordinated Universal Time) or GPS (Global Positioning System)
-time lines.</p>
-<p>If not specified, the default time base must be considered to be
-<code>media</code>.</p>
-<p>A <att>ttp:timeBase</att> attribute is considered to be significant only
-when specified on the <el>tt</el> element.</p>
-<p>When operating with either <code>media</code> or <code>smpte</code>
-time bases, a diachronic presentation of a document instance may
-be subject to transformations of the controlling time line, such as
-temporal reversal, dilation (expansion), or constriction
-(compression); however, when operating with the <code>clock</code>
-time base, no transformations are permitted, and diachronic
-presentation proceeds on a linear, monotonically increasing time line
-based on the passage of real time.</p>
-<note role="example">
-<p>Due to there being only one time base parameter that applies to a
-given document instance, the interpretation of time expressions
-is uniform throughout the document instance.</p>
-</note>
-<p>When operating with the <code>clock</code> time base,
-the expression <emph>media time</emph> as used in this specification is
-to be interpreted as the real-time clock selected by
-<specref ref="parameter-attribute-clockMode"/>.</p>
-</div3>
-</div2>
-</div1>
-<div1 id="content">
-<head>Content</head>
-<p>This section specifies the <emph>content</emph> matter of the core
-vocabulary catalog.</p>
-<div2 id="content-element-vocabulary">
-<head>Content Element Vocabulary</head>
-<p>The following elements specify the structure and principal content aspects of a
-document instance:</p>
-<ulist>
-<item><p><specref ref="document-structure-vocabulary-tt"/></p></item>
-<item><p><specref ref="document-structure-vocabulary-head"/></p></item>
-<item><p><specref ref="document-structure-vocabulary-body"/></p></item>
-<item><p><specref ref="content-vocabulary-div"/></p></item>
-<item><p><specref ref="content-vocabulary-p"/></p></item>
-<item><p><specref ref="content-vocabulary-span"/></p></item>
-<item><p><specref ref="content-vocabulary-br"/></p></item>
-</ulist>
-<div3 id="document-structure-vocabulary-tt">
-<head>tt</head>
-<p>The <el>tt</el> element serves as the root document element of a document
-instance.</p>
-<p>The <el>tt</el> element accepts as its children zero or one <el>head</el> element followed by
-zero or one <el>body</el> element.</p>
-<table id="elt-syntax-tt" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: tt</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;tt
-  <loc href="#style-attribute-extent">tts:extent</loc> = string
-  <loc href="#content-attribute-id">xml:id</loc> = ID
-  <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 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;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>The temporal beginning and ending of a document instance represented by a
-<el>tt</el> element is defined in relationship with some external
-application or presentation context. The temporal interval defined by
-these points is referred to subsequently as the <emph>external time interval</emph>.
-</p>
-<p>A document instance has an implicit duration that is equal to the
-implicit duration of the <el>body</el> element of the document, if present, or zero,
-if not present.</p>
-<p>If the <att>tts:extent</att> attribute is specified on the <el>tt</el>
-element, then it must adhere to <specref ref="style-attribute-extent"/>, in which case it
-specifies the spatial extent of the root container region in
-which content regions are located and presented. If no <att>tts:extent</att>
-attribute is specified, then the spatial extent of the root container region is
-considered to be determined by the external authoring or presentation
-context. The root container origin is determined by the external
-authoring context.</p>
-<p>An <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 document instance.</p>
-<p>If no <att>xml:space</att> attribute is specified upon the <el>tt</el> element, then it must
-be considered as if the attribute had been specified with a value of <code>default</code>.</p>
-</div3>
-<div3 id="document-structure-vocabulary-head">
-<head>head</head>
-<p>The <el>head</el> element is a container element used to group
-header matter, including metadata,
-profile, styling, and layout information.</p>
-<p>The <el>head</el> element accepts as its children zero or more
-elements in the <code>Metadata.class</code> element group,
-followed by zero or more elements in the
-<code>Parameters.class</code> element group,
-followed by zero or one <el>styling</el> element,
-followed by zero or one <el>layout</el> element.</p>
-<p>Any metadata specified by children in the <code>Metadata.class</code>
-element group applies semantically to the document instance as a
-whole, and not just the <el>head</el> element.</p>
-<p>Any parameters specified by children in the <code>Parameters.class</code>
-element group applies semantically to the document instance as a
-whole, and not just the <el>head</el> element.</p>
-<p>A <el>styling</el> child element is used to specify style constructs
-that are referenced from other style constructs, by layout constructs, and by
-content elements.</p>
-<p>A <el>layout</el> child element is used to specify layout constructs that
-are referenced by content elements.</p>
-<table id="elt-syntax-head" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: head</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;head
-  <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 not in default or any TT namespace</emph>}&gt;
-  <emph>Content:</emph> <loc href="#element-vocab-group-table">Metadata.class</loc>*, <loc href="#element-vocab-group-table">Parameters.class</loc>*, <loc href="#styling-vocabulary-styling">styling</loc>?, <loc href="#layout-vocabulary-layout">layout</loc>?
-&lt;/head&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>To the extent that time semantics apply to the content of the
-<el>head</el> element, the implied time interval of this element is
-defined to be coterminous with the external time interval.</p>
-</div3>
-<div3 id="document-structure-vocabulary-body">
-<head>body</head>
-<p>The <el>body</el> element functions as a logical container and a temporal
-structuring element for a sequence of textual content units represented as
-logical divisions.</p>
-<p>The <el>body</el> element accepts as its children zero or more
-elements in the <code>Metadata.class</code> element group,
-followed by zero or more
-elements in the <code>Animation.class</code> element group,
-followed by
-zero or more <el>div</el> elements.</p>
-<p>Any metadata specified by children in the <code>Metadata.class</code>
-element group applies semantically to the <el>body</el> element and its descendants as a whole.</p>
-<p>Any animation elements specified by children in the <code>Animation.class</code>
-element group apply semantically to the <el>body</el> element.</p>
-<table id="elt-syntax-body" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: body</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;body
-  <loc href="#timing-attribute-begin">begin</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#timing-attribute-dur">dur</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#timing-attribute-end">end</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#layout-attribute-region">region</loc> = IDREF
-  <loc href="#style-attribute-style">style</loc> = IDREFS
-  <loc href="#timing-attribute-timeContainer">timeContainer</loc> = (<emph>par</emph>|<emph>seq</emph>)
-  <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 Metadata 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="#element-vocab-group-table">Metadata.class</loc>*, <loc href="#element-vocab-group-table">Animation.class</loc>*, <loc href="#content-vocabulary-div">div</loc>*
-&lt;/body&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>An author may specify a temporal interval for a <el>body</el> element using
-the <att>begin</att>, <att>dur</att>, and <att>end</att> attributes. If the begin point
-of this interval remains unspecified, then the begin point is interpreted as the begin
-point of the external time interval. Similarly, if the end point of this interval remains unspecified, then the
-end point is interpreted as the end point of the external time interval.</p>
-<note role="explanation">
-<p>A TTML document instance referenced from a SMIL presentation
-is expected to follow the same timing rules as apply to other SMIL media
-objects.</p>
-</note>
-<p>If relative begin or end times are specified on the <el>body</el>
-element, then these times are resolved by reference to the begin and
-end time of the external time interval.</p>
-<p>If the external time interval is shorter than the computed duration of the
-<el>body</el> element, then the active time interval of a document instance is
-truncated to the active end point of the external time interval.</p>
-<p>An author may associate a set of style properties with a
-<el>body</el> element by means of either the <att>style</att>
-attribute or inline style attributes or a combination thereof.</p>
-<note role="explanation">
-<p>Style properties that are associated with a <el>body</el> element
-in a document instance are available for style inheritance by
-descendant content elements such as <el>div</el>, <el>p</el>,
-<el>span</el>
-and <el>br</el>.</p>
-</note>
-<p>If no <att>timeContainer</att> attribute is specified on a
-<el>body</el> element, then it must be interpreted as having
-<emph>parallel</emph>
-time containment semantics.</p>
-</div3>
-<div3 id="content-vocabulary-div">
-<head>div</head>
-<p>The <el>div</el> element functions as a logical container and a temporal
-structuring element for a sequence of textual content units represented as
-logical sub-divisions or paragraphs.</p>
-<note role="explanation">
-<p>When rendered on a continuous (non-paged) visual presentation medium,
-a <el>div</el> element is expected to generate
-one or more block
-areas
-that contain zero or more child block areas
-generated by the <el>div</el> element's
-descendant
-<el>p</el> elements.
-</p>
-<p>If some
-block area generated by a <el>div</el> element does
-not contain any child areas, then it is not expected to be presented.</p>
-</note>
-<p>The <el>div</el> element accepts as its children zero or more
-elements in the <code>Metadata.class</code> element group,
-followed by zero or more
-elements in the <code>Animation.class</code> element group,
-followed by
-zero or more
-<el>div</el> or 
-<el>p</el> elements.</p>
-<p>Any metadata specified by children in the <code>Metadata.class</code>
-element group applies semantically to the <el>div</el> element and its descendants as a whole.</p>
-<p>Any animation elements specified by children in the <code>Animation.class</code>
-element group apply semantically to the <el>div</el> element.</p>
-<table id="elt-syntax-div" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: div</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;div
-  <loc href="#timing-attribute-begin">begin</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#timing-attribute-dur">dur</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#timing-attribute-end">end</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#layout-attribute-region">region</loc> = IDREF
-  <loc href="#style-attribute-style">style</loc> = IDREFS
-  <loc href="#timing-attribute-timeContainer">timeContainer</loc> = (<emph>par</emph>|<emph>seq</emph>)
-  <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 Metadata 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="#element-vocab-group-table">Metadata.class</loc>*, <loc
-  href="#element-vocab-group-table">Animation.class</loc>*, <loc
-  href="#element-vocab-group-table">Block.class</loc>*
-&lt;/div&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>An author may associate a set of style properties with a <el>div</el> element by means of either
-the <att>style</att> attribute or inline style attributes or a combination thereof.</p>
-<note role="explanation">
-<p>Style properties that are associated
-with
-a <el>div</el> element in a document instance
-are available for style inheritance by descendant content elements such as
-<el>div</el>, 
-<el>p</el>,
-<el>span</el>, and
-<el>br</el>.</p>
-</note>
-<p>If no <att>timeContainer</att> attribute is specified on
-a <el>div</el> element, then it must be interpreted as having
-<emph>parallel</emph> time containment semantics.</p>
-</div3>
-<div3 id="content-vocabulary-p">
-<head>p</head>
-<p>A <el>p</el> element represents a logical paragraph, serving as
-a transition between block level and inline level formatting semantics.</p>
-<p>The <el>p</el> element accepts as its children zero or more
-elements in the <code>Metadata.class</code> element group,
-followed by zero or more
-elements in the <code>Animation.class</code> element group,
-followed by
-zero or more
-<code>span</code> element,
-<code>br</code> element,
-or text nodes interpreted as anonymous spans.</p>
-<p>Any metadata specified by children in the <code>Metadata.class</code>
-element group applies semantically to the <el>p</el> element and its descendants as a whole.</p>
-<p>Any animation elements specified by children in the <code>Animation.class</code>
-element group apply semantically to the <el>p</el> element.</p>
-<table id="elt-syntax-p" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: p</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;p
-  <loc href="#timing-attribute-begin">begin</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#timing-attribute-dur">dur</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#timing-attribute-end">end</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#layout-attribute-region">region</loc> = IDREF
-  <loc href="#style-attribute-style">style</loc> = IDREFS
-  <loc href="#timing-attribute-timeContainer">timeContainer</loc> = (<emph>par</emph>|<emph>seq</emph>)
-  <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 Metadata 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="#element-vocab-group-table">Metadata.class</loc>*, <loc
-  href="#element-vocab-group-table">Animation.class</loc>*, <loc
-  href="#element-vocab-group-table">Inline.class</loc>*
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>An author may associate a set of style properties with a
-<el>p</el> element by means of either the <att>style</att>
-attribute or inline style attributes or a combination thereof.</p>
-<note role="explanation">
-<p>Style properties that are associated with a <el>p</el> element
-in a document instance are available for style inheritance by
-descendant content elements such as <el>span</el> and
-<el>br</el>.</p>
-</note>
-<p>If no <att>timeContainer</att> attribute is specified on
-a <el>p</el> element, then it must be interpreted as having
-<emph>parallel</emph> time containment semantics.</p>
-<p>If a sequence of children of a <el>p</el> element
-consists solely of character information items, then that sequence must
-be considered to be an <emph>anonymous span</emph> for the purpose of
-applying style properties that apply to <el>span</el> elements.</p>
-</div3>
-<div3 id="content-vocabulary-span">
-<head>span</head>
-<p>The <el>span</el> element functions as a logical container and a temporal
-structuring element for a sequence of textual content units having inline
-level formatting semantics.</p>
-<p>When presented on a visual medium, a <el>span</el> element is intended to
-generate a sequence of inline areas, each containing one or more glyph areas.</p>
-<p>The <el>span</el> element accepts as its children zero or more
-elements in the <code>Metadata.class</code> element group,
-followed by zero or more
-elements in the <code>Animation.class</code> element group,
-followed by
-zero or more
-<el>span</el> elements,
-<el>br</el> elements,
-or text nodes interpreted as anonymous spans.</p>
-<p>Any metadata specified by children in the <code>Metadata.class</code>
-element group applies semantically to the <el>span</el> element and its descendants as a whole.</p>
-<p>Any animation elements specified by children in the <code>Animation.class</code>
-element group apply semantically to the <el>span</el> element.</p>
-<table id="elt-syntax-span" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: span</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;span
-  <loc href="#timing-attribute-begin">begin</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#timing-attribute-dur">dur</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#timing-attribute-end">end</loc> = <loc href="#timing-value-timeExpression">&lt;timeExpression&gt;</loc>
-  <loc href="#layout-attribute-region">region</loc> = IDREF
-  <loc href="#style-attribute-style">style</loc> = IDREFS
-  <loc href="#timing-attribute-timeContainer">timeContainer</loc> = (<emph>par</emph>|<emph>seq</emph>)
-  <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 Metadata 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="#element-vocab-group-table">Metadata.class</loc>*, <loc
-  href="#element-vocab-group-table">Animation.class</loc>*, <loc
-  href="#element-vocab-group-table">Inline.class</loc>*
-&lt;/span&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>An author may associate a set of style properties with a
-<el>span</el> element by means of either the <att>style</att>
-attribute or inline style attributes or a combination thereof.</p>
-<note role="explanation">
-<p>Style properties that are associated with a <el>span</el> element
-in a document instance are available for style inheritance by
-descendant content elements such as <el>span</el> and
-<el>br</el>.</p>
-</note>
-<p>If no <att>timeContainer</att> attribute is specified on
-a <el>span</el> element, then it must be interpreted as having
-<emph>parallel</emph> time containment semantics.</p>
-</div3>
-<div3 id="content-vocabulary-br">
-<head>br</head>
-<p>The <el>br</el> element denotes an explicit line break.</p>
-<table id="elt-syntax-br" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: br</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;br
-  <loc href="#style-attribute-style">style</loc> = IDREFS
-  <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 Metadata 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="#element-vocab-group-table">Metadata.class</loc>*, <loc href="#element-vocab-group-table">Animation.class</loc>*
-&lt;/br&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>When presented on a visual medium, the presence of a <el>br</el> element must be
-interpreted as a forced line break.</p>
-<note>
-<p>The visual presentation of a <el>br</el> element is
-intended to produce the same effect as the ASCII control code
-<code>CR</code>
-followed by the control code <code>NL</code> when presented on a teletype device.
-Therefore, two <el>br</el> elements in sequence will produce a
-different effect than a single <el>br</el> element.</p>
-</note>
-</div3>
-</div2>
-<div2 id="content-attribute-vocabulary">
-<head>Content Attribute Vocabulary</head>
-<p>This section defines the following common attributes used with many or all element types
-in the core vocabulary catalog:</p>
-<ulist>
-<item><p><specref ref="content-attribute-id"/></p></item>
-<item><p><specref ref="content-attribute-lang"/></p></item>
-<item><p><specref ref="content-attribute-space"/></p></item>
-</ulist>
-<div3 id="content-attribute-id">
-<head>xml:id</head>
-<p>The <att>xml:id</att> attribute is used as defined by
-<bibref ref="xmlid"/>.</p>
-<p>The <att>xml:id</att> attribute may be used with any element in the
-core vocabulary catalog.</p>
-</div3>
-<div3 id="content-attribute-lang">
-<head>xml:lang</head>
-<p>The <att>xml:lang</att> attribute is used as defined by
-<bibref ref="xml10"/>, &sect;2.12, <emph>Language Identification</emph>.</p>
-<p>The <att>xml:lang</att> attribute must be specified on the <el>tt</el>
-element and may be specified by an instance of any other element type
-in the core vocabulary catalog.</p>
-</div3>
-<div3 id="content-attribute-space">
-<head>xml:space</head>
-<p>The <att>xml:space</att> attribute is used as defined by
-<bibref ref="xml10"/>, &sect;2.10, <emph>White Space Handling</emph>.</p>
-<p>The <att>xml:space</att> attribute may be used with any element in
-the core vocabulary catalog.</p>
-<!-- OLD DEFINITION
-<p>The semantics of the value <code>default</code> are fixed to mean that
-white space that appears in element content as defined by <bibref
-ref="xml10"/>, &sect;3.2.1, must be normalized at the
-application layer during subsequent processing, such as presentation or
-transformation processing, as follows:</p>
-<olist>
-<item><p>replace each TAB character (<code>&amp;#x0009;</code>) and NEWLINE character (<code>&amp;#x000A;</code>) with a SPACE
-character (<code>&amp;#x0020;</code>);</p></item>
-<item><p>replace each sequence of two or more SPACE characters with a
-single SPACE character;</p></item>
-<item><p>for every maximum sequence of sibling character information
-items, if there is a leading or trailing SPACE character in the
-sequence, then remove the character.</p></item>
-</olist>
--->
-<!-- NEW DEFINITION -->
-<p>The semantics of the value <code>default</code> are fixed to mean that
-when performing presentation processing of a document instance as
-described by <specref ref="semantics-region-layout-step-2"/>,
-processing must occur as
-if the following properties were specified on the affected
-<!-- changed for future CSS compatibility
-elements of the intermediate XSL-FO document:</p> 
--->
-elements of an equivalent intermediate XSL-FO document:</p>
-<ulist>
-<item>
-<p><code>suppress-at-line-break="auto"</code></p>
-</item>
-<item>
-<p><code>linefeed-treatment="treat-as-space"</code></p>
-</item>
-<item>
-<p><code>white-space-collapse="true"</code></p>
-</item>
-<item>
-<p><code>white-space-treatment="ignore-if-surrounding-linefeed"</code></p>
-</item>
-</ulist>
-<p>Similarly, the semantics of the value <code>preserve</code> are fixed to mean that
-when performing presentation processing, processing must occur as
-if the following properties were specified on the affected
-<!-- changed for future CSS compatibility
-elements of the intermediate XSL-FO document:</p> 
--->
-elements of an equivalent intermediate XSL-FO document:
-</p>
-<ulist>
-<item>
-<p><code>suppress-at-line-break="retain"</code></p>
-</item>
-<item>
-<p><code>linefeed-treatment="preserve"</code></p>
-</item>
-<item>
-<p><code>white-space-collapse="false"</code></p>
-</item>
-<item>
-<p><code>white-space-treatment="preserve"</code></p>
-</item>
-</ulist>
-<p>When performing other types of processing intended to eventually
-result in a visual presentation by means other than those described
-in this specification, the semantics of space collapsing and
-preservation as described above should be respected. For other types
-of processing, the treatment of the <att>xml:space</att> attribute
-is processor dependent, but should respect the semantics described
-above if possible.</p>
-</div3>
-</div2>
-</div1>
-<div1 id="styling">
-<head>Styling</head>
-<p>This section specifies the <emph>styling</emph> matter of the core
-vocabulary catalog, where
-styling is to be understood as a separable layer of information that applies to
-content and that denotes authorial intentions about the presentation of
-that content.</p>
-  <!-- added for future CSS compatibility -->
-  <p>
-    Styling attributes are included in TTML to enable authorial intent of presentation
-    to be included within a self-contained document. This section describes
-    the semantics of style presentation in terms of a standard processing
-    model. TTML Processors are not required to present TTML documents in any particular way; 
-    but an implementation of this model by a TTML Presentation Processor
-    that provides externally observable results that are consistent with this model is
-    likely to lead to a user experience that closely resembles the experience intended by
-    the documents' authors.
-  </p>
-  <p>
-    The semantics of TTML style presentation are described in terms of the model 
-    in <bibref ref="xsl11"/>. The intended effect of the attributes in this section 
-    are to be compatible with  the layout model of XSL. Presentation agents may however 
-    use any technology to satisfy the authorial intent of the document. In particular 
-    since <bibref ref="css2"/> is a subset of this model, a CSS processor may be used 
-    for the features that the models have in common.
-  </p>
-  <!-- end addition -->
-  <p>No normative use of an
-<code>&lt;?xml-stylesheet ... ?&gt;</code> processing instruction is defined
-by this specification.</p>
-<div2 id="styling-element-vocabulary">
-<head>Styling Element Vocabulary</head>
-<p>The following elements specify the structure and principal styling aspects of a
-document instance:</p>
-<ulist>
-<item><p><specref ref="styling-vocabulary-styling"/></p></item>
-<item><p><specref ref="styling-vocabulary-style"/></p></item>
-</ulist>
-<div3 id="styling-vocabulary-styling">
-<head>styling</head>
-<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>
-<table id="elt-syntax-styling" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: styling</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;styling
-  <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 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>*
-&lt;/styling&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>To the extent that time semantics apply to the content of the
-<el>styling</el> element, the implied time interval of this element is
-defined to be coterminous with the external time interval.</p>
-</div3>
-<div3 id="styling-vocabulary-style">
-<head>style</head>
-<p>The <el>style</el> element is used to define
-a set of style specifications expressed as a
-specified style set in accordance with
-<specref ref="semantics-style-resolution-processing-sss"/>.</p>
-<p>The <el>style</el> element accepts as its children zero or more <el>metadata</el> elements.</p>
-<table id="elt-syntax-style" role="syntax">
-<caption>XML Representation &ndash; Element Information Item: style</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;style
-  <loc href="#style-attribute-style">style</loc> = IDREFS
-  <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;
-  <!-- change for future CSS compatibility
-  <emph>Content:</emph> <loc href="#element-vocab-group-table">Metadata.class</loc>*
-  -->
-  <emph>Content:</emph> EMPTY
-&lt;/style&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>If a <el>style</el> element appears as a descendant of a
-<el>region</el> element, then the <el>style</el> element must be
-ignored for the purpose of computing referential styles as defined by
-<specref ref="semantics-style-association-referential"/> and <specref
-ref="semantics-style-association-chained-referential"/>.</p>
-<note role="explanation">
-<p>That is to say, when referential styling is used by an element to
-refer to a <el>style</el> element, then the referenced <el>style</el>
-element must appear as a descendant of the <el>styling</el> element, and
-not in any other context.</p>
-</note>
-</div3>
-</div2>
-<div2 id="styling-attribute-vocabulary">
-<head>Styling Attribute Vocabulary</head>
-<p>This section defines the <specref ref="style-attribute-style"/> attribute used
-with both style definition elements as well as content elements.</p>
-<p>In addition, this section specifies the following attributes in the TT Style Namespace
-for use with style definition elements, certain layout elements, and content elements
-that support inline style specifications:</p>
-<ulist>
-<item><p><specref ref="style-attribute-backgroundColor"/></p></item>
-<item><p><specref ref="style-attribute-color"/></p></item>
-<item><p><specref ref="style-attribute-direction"/></p></item>
-<item><p><specref ref="style-attribute-display"/></p></item>
-<item><p><specref ref="style-attribute-displayAlign"/></p></item>
-<item><p><specref ref="style-attribute-extent"/></p></item>
-<item><p><specref ref="style-attribute-fontFamily"/></p></item>
-<item><p><specref ref="style-attribute-fontSize"/></p></item>
-<item><p><specref ref="style-attribute-fontStyle"/></p></item>
-<item><p><specref ref="style-attribute-fontWeight"/></p></item>
-<item><p><specref ref="style-attribute-lineHeight"/></p></item>
-<item><p><specref ref="style-attribute-opacity"/></p></item>
-<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-showBackground"/></p></item>
-<item><p><specref ref="style-attribute-textAlign"/></p></item>
-<item><p><specref ref="style-attribute-textDecoration"/></p></item>
-<item><p><specref ref="style-attribute-textOutline"/></p></item>
-<item><p><specref ref="style-attribute-unicodeBidi"/></p></item>
-<item><p><specref ref="style-attribute-visibility"/></p></item>
-<item><p><specref ref="style-attribute-wrapOption"/></p></item>
-<item><p><specref ref="style-attribute-writingMode"/></p></item>
-<item><p><specref ref="style-attribute-zIndex"/></p></item>
-</ulist>
-<p>Unless explicitly stated otherwise, linear white-space (LWSP) may
-appear between tokens of a value of a TT
-Style or TT Style Extension
-Property.</p>
-<note role="explanation">
-<p>This specification makes use of <emph>lowerCamelCased</emph> local
-names for style attributes that
-are based upon like-named properties defined by <bibref ref="xsl11"/>.
-This convention is likewise extended to token values of such
-properties.</p>
-</note>
-<note role="clarification">
-<p>A style property may be expressed as a specified attribute on any content
-element type independently of whether the property applies to that
-element type. This capability permits the expression of an inheritable
-style property on ancestor elements to which the property
-does not apply.</p>
-</note>
-<div3 id="style-attribute-style">
-<head>style</head>
-<p>The <att>style</att> attribute is used
-by referential style association
-to reference one or more <el>style</el>
-elements each of which define a
-specified
-style set.</p>
-<p>The <att>style</att> attribute may be specified by an instance of the following
-element types:</p>
-<ulist>
-<item><p><loc href="#document-structure-vocabulary-body"><el>body</el></loc></p></item>
-<item><p><loc href="#content-vocabulary-div"><el>div</el></loc></p></item>
-<item><p><loc href="#content-vocabulary-p"><el>p</el></loc></p></item>
-<item><p><loc href="#layout-vocabulary-region"><el>region</el></loc></p></item>
-<item><p><loc href="#content-vocabulary-span"><el>span</el></loc></p></item>
-<item><p><loc href="#styling-vocabulary-style"><el>style</el></loc></p></item>
-</ulist>
-<note role="usage">
-<p>See the specific element type definitions that permit use of the
-<att>style</att> attribute, as well as <specref
-ref="semantics-style-association-referential"/> and <specref
-ref="semantics-style-association-chained-referential"/>, for
-further information on its semantics.</p>
-</note>
-</div3>
-<div3 id="style-attribute-backgroundColor">
-<head>tts:backgroundColor</head>
-<p>The <att>tts:backgroundColor</att> attribute is used to specify a style property that
-defines the background color of a region or an area generated by content flowed into a region.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-backgroundColor" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<loc href="#style-value-color">&lt;color&gt;</loc>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>transparent</code></td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#document-structure-vocabulary-body"><el>body</el></loc>,
-<loc href="#content-vocabulary-div"><el>div</el></loc>,
-<loc href="#content-vocabulary-p"><el>p</el></loc>,
-<loc href="#layout-vocabulary-region"><el>region</el></loc>,
-<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>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>The <att>tts:backgroundColor</att> style is illustrated by the following example.</p>
-<table id="style-attribute-backgroundColor-example-1" role="example">
-<caption>Example Fragment &ndash; Background Color</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="306px 114px"/&gt;
-  &lt;style <phrase role="strong">tts:backgroundColor="red"</phrase>/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="after"/&gt;
-  &lt;style tts:padding="3px 40px"/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1" <phrase role="strong">tts:backgroundColor="purple"</phrase> tts:textAlign="center"&gt;
-  Twinkle, twinkle, little bat!&lt;br/&gt;
-  How &lt;span <phrase role="strong">tts:backgroundColor="green"</phrase>&gt;I wonder&lt;/span&gt; where you're at!
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-backgroundColor-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Background Color</caption>
-<tbody>
-<tr>
-<td><graphic source="images/backgroundColor.png" alt="TTML backgroundColor style property"/></td>
-</tr>
-</tbody>
-</table>
-  <!-- CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property represented by this attribute are based upon 
-that defined by <bibref ref="xsl11"/>, &sect; 7.8.2.</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
-defines the foreground color of marks associated with an area generated by content flowed into a region.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-color" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<loc href="#style-value-color">&lt;color&gt;</loc>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td>see prose</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>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>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>The initial value of the <att>tts:color</att> property
-is considered to be implementation dependent. In the absence of
-end-user preference information, a conformant presentation processor
-should use an initial value that is highly contrastive to the
-background color of the root container region.</p>
-<p>The <att>tts:color</att> style is illustrated by the following example.</p>
-<table id="style-attribute-color-example-1" role="example">
-<caption>Example Fragment &ndash; Color</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style <phrase role="strong">tts:color="white"</phrase>/&gt;
-  &lt;style tts:displayAlign="after"/&gt;
-  &lt;style tts:textAlign="center"/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  In spring, when woods are &lt;span <phrase role="strong">tts:color="green"</phrase>&gt;getting green&lt;/span&gt;,&lt;br/&gt;
-  I'll try and tell you what I mean.
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-color-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Color</caption>
-<tbody>
-<tr>
-<td><graphic source="images/color.png" alt="TTML color style property"/></td>
-</tr>
-</tbody>
-</table>
-  <!-- CSS compatibility - remove derivation note 
-  <note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.18.1.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-direction">
-<head>tts:direction</head>
-<p>The <att>tts:direction</att> attribute is used to specify a style property that
-defines the directionality of an embedding or override according to
-the Unicode bidirectional algorithm.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-direction" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>ltr</code> |
-<code>rtl</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td>
-<code>ltr</code>
-</td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#content-vocabulary-p"><el>p</el></loc>,
-<loc href="#content-vocabulary-span"><el>span</el></loc>
-</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>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must ignore the attribute.</p>
-<p>The <att>tts:direction</att> style is illustrated by the following example.</p>
-<table id="style-attribute-direction-example-1" role="example">
-<caption>Example Fragment &ndash; Direction</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="265px 84px"/&gt;
-  &lt;style tts:padding="5px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="after"/&gt;
-  &lt;style tts:textAlign="center"/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  Little birds are playing&lt;br/&gt;
-  Bagpipes on the shore,&lt;br/&gt;
-  &lt;span tts:unicodeBidi="bidiOverride" <phrase role="strong">tts:direction="rtl"</phrase>&gt;where the tourists snore.&lt;/span&gt;
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-direction-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Direction</caption>
-<tbody>
-<tr>
-<td>
-<graphic source="images/direction.png" alt="TTML direction style property"/>
-</td>
-</tr>
-</tbody>
-</table>
-  <!-- CSS compatibility - remove derivation note 
-  <note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.29.1.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-display">
-<head>tts:display</head>
-<p>The <att>tts:display</att> attribute is used to specify a style property that
-defines whether an element is a candidate for layout and composition
-in a region.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-display" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>auto</code> |
-<code>none</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td>
-<code>auto</code>
-</td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#document-structure-vocabulary-body"><el>body</el></loc>,
-<loc href="#content-vocabulary-div"><el>div</el></loc>,
-<loc href="#content-vocabulary-p"><el>p</el></loc>,
-<loc href="#layout-vocabulary-region"><el>region</el></loc>,
-<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>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>If the value of this attribute is <code>auto</code>,
-then the affected element is a candidate for region layout and
-presentation; however, if the value is <code>none</code>, then the
-affected element and its descendants must be considered ineligible for region
-layout and presentation.</p>
-<p>The <att>tts:display</att> style is illustrated by the following example.</p>
-<table id="style-attribute-display-example-1" role="example">
-<caption>Example Fragment &ndash; Display</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="369px 119px"
-            tts:backgroundColor="black"
-            tts:color="white"
-            tts:displayAlign="before"
-            tts:textAlign="start"/&gt;
-&lt;/region&gt;
-...
-&lt;div region="r1"&gt;
-  &lt;p dur="5s"&gt;
-    [[[
-    &lt;span <phrase role="strong">tts:display="none"</phrase>&gt;
-      &lt;set begin="1s" dur="1s" <phrase role="strong">tts:display="auto"</phrase>/&gt;
-      Beautiful soup,
-    &lt;/span&gt;
-    &lt;span <phrase role="strong">tts:display="none"</phrase>&gt;
-      &lt;set begin="2s" dur="1s" <phrase role="strong">tts:display="auto"</phrase>/&gt;
-      so rich and green,
-    &lt;/span&gt;
-    &lt;span <phrase role="strong">tts:display="none"</phrase>&gt;
-      &lt;set begin="3s" dur="1s" <phrase role="strong">tts:display="auto"</phrase>/&gt;
-      waiting in a hot tureen!
-    &lt;/span&gt;
-    ]]]
-  &lt;/p&gt;
-&lt;/div&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-display-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Display</caption>
-<tbody>
-<tr>
-<td>
-<graphic source="images/display_0.png" alt="TTML display style property - [0,1)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/display_1.png" alt="TTML display style property - [1,2)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/display_2.png" alt="TTML display style property - [2,3)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/display_3.png" alt="TTML display style property - [3,4)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/display_4.png" alt="TTML display style property - [4,5)"/>
-</td>
-</tr>
-</tbody>
-</table>
-  <!-- CSS compatibility - remove derivation note 
-  <note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref
-ref="css2"/>,
-&sect; 9.2.5.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-displayAlign">
-<head>tts:displayAlign</head>
-<p>The <att>tts:displayAlign</att> attribute is used to specify a style property that
-defines the alignment of block areas in the block progression direction.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-displayAlign" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>before</code> |
-<code>center</code> |
-<code>after</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td>
-<code>before</code>
-</td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#layout-vocabulary-region"><el>region</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>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>before</code> were specified.</p>
-<p>The <att>tts:displayAlign</att> style is illustrated by the following example.</p>
-<table id="style-attribute-displayAlign-example-1" role="example">
-<caption>Example Fragment &ndash; Display Align</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="128px 66px"/&gt;
-  &lt;style tts:origin="0px 0px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style <phrase role="strong">tts:displayAlign="before"</phrase>/&gt;
-  &lt;style tts:textAlign="start"/&gt;
-&lt;/region&gt;
-&lt;region xml:id="r2"&gt;
-  &lt;style tts:extent="192px 66px"/&gt;
-  &lt;style tts:origin="128px 66px"/&gt;
-  &lt;style tts:backgroundColor="green"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style <phrase role="strong">tts:displayAlign="after"</phrase>/&gt;
-  &lt;style tts:textAlign="start"/&gt;
-&lt;/region&gt;
-&lt;region xml:id="r3"&gt;
-  &lt;style tts:extent="128px 66px"/&gt;
-  &lt;style tts:origin="0px 132px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style <phrase role="strong">tts:displayAlign="before"</phrase>/&gt;
-  &lt;style tts:textAlign="start"/&gt;
-&lt;/region&gt;
-&lt;region xml:id="r4"&gt;
-  &lt;style tts:extent="192px 66px"/&gt;
-  &lt;style tts:origin="128px 198px"/&gt;
-  &lt;style tts:backgroundColor="green"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style <phrase role="strong">tts:displayAlign="after"</phrase>/&gt;
-  &lt;style tts:textAlign="start"/&gt;
-&lt;/region&gt;
-...
-&lt;div&gt;
-  &lt;p region="r1"&gt;I sent a message to the fish:&lt;/p&gt;
-  &lt;p region="r2"&gt;I told them&lt;br/&gt; "This is what I wish."&lt;/p&gt;
-  &lt;p region="r3"&gt;The little fishes of the sea,&lt;/p&gt;
-  &lt;p region="r4"&gt;They sent an&lt;br/&gt; answer back to me.&lt;/p&gt;
-&lt;/div&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-displayAlign-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Display Align</caption>
-<tbody>
-<tr>
-<td><graphic source="images/displayAlign.png" alt="TTML displayAlign style property"/></td>
-</tr>
-</tbody>
-</table>
-<!-- CSS compatibility - remove derivation note   
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.14.4.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-extent">
-<head>tts:extent</head>
-<p>The <att>tts:extent</att> attribute is used to specify the
-<emph>width</emph> and <emph>height</emph> of a region area
-(which may be the root container region).</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-extent" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>auto</code> |
-<loc href="#style-value-length">&lt;length&gt;</loc> <loc href="#style-value-length">&lt;length&gt;</loc>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>auto</code></td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#document-structure-vocabulary-tt"><el>tt</el></loc>,
-<loc href="#layout-vocabulary-region"><el>region</el></loc>
-</td>
-</tr>
-<tr>
-<td><emph>Inherited:</emph></td>
-<td>no</td>
-</tr>
-<tr>
-<td><emph>Percentages:</emph></td>
-<td>relative to width and height of root container region</td>
-</tr>
-<tr>
-<td><emph>Animatable:</emph></td>
-<td>discrete</td>
-</tr>
-</tbody>
-</table>
-<p>If the value of this attribute consists of two <loc href="#style-value-length">&lt;length&gt;</loc>
-specifications, then they must be interpreted as <emph>width</emph>
-and <emph>height</emph>, where the first specification is the
-<emph>width</emph>, and the second specification is the
-<emph>height</emph>.</p>
-<p>If the value of this attribute is <code>auto</code>, then the initial value
-of the style property must be considered to be the same as the root container extent.
-</p>
-<p>
-The root container extent is determined either by a
-<att>tts:extent</att> specified on the <el>tt</el> element, if
-present, or by the external authoring context, if not present.
-If
-<att>tts:extent</att> is specified on the <el>tt</el> element,
-then
-the width and height
-must be
-expressed in terms of two
-<loc href="#style-value-length">&lt;length&gt;</loc> specifications,
-and
-these specifications must be expressed as non-percentage,
-definite lengths using pixel units.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>auto</code> were specified.</p>
-<p>The <att>tts:extent</att> style is illustrated by the following example.</p>
-<table id="style-attribute-extent-example-1" role="example">
-<caption>Example Fragment &ndash; Extent</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style <phrase role="strong">tts:extent="330px 122px"</phrase>/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="after"/&gt;
-  &lt;style tts:textAlign="center"/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  'Tis the voice of the Lobster:&lt;br/&gt;
-  I heard him declare,&lt;br/&gt;
-  "You have baked me too brown,&lt;br/&gt;
-  I must sugar my hair."
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-extent-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Extent</caption>
-<tbody>
-<tr>
-<td><graphic source="images/extent.png" alt="TTML extent style property"/></td>
-</tr>
-</tbody>
-</table>
-</div3>
-<div3 id="style-attribute-fontFamily">
-<head>tts:fontFamily</head>
-<p>The <att>tts:fontFamily</att> attribute is used to specify a style property that
-defines the font family from which glyphs are selected for glyph areas generated
-by content flowed into a region.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-fontFamily" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-(<loc href="#style-value-familyName">&lt;familyName&gt;</loc> | <loc href="#style-value-genericFamilyName">&lt;genericFamilyName&gt;</loc>)
-(<code>","</code>
-&nbsp;(<loc href="#style-value-familyName">&lt;familyName&gt;</loc> | <loc href="#style-value-genericFamilyName">&lt;genericFamilyName&gt;</loc>))*
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>default</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>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>
-<note role="clarification">
-<p>The initial value, <code>default</code>, is a generic font family name, and is
-further described in <specref ref="style-value-genericFamilyName"/> below.</p>
-</note>
-<p>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>If a specified font family is not available, then a
-presentation processor must attempt to map the specified font family
-to an available font family that has similar typographic
-characteristics, or, in the absence of such a mapping, it must
-interpret the font family as if the value <code>default</code> were
-specified.</p>
-<p>The <att>tts:fontFamily</att> style is illustrated by the following example.</p>
-<table id="style-attribute-fontFamily-example-1" role="example">
-<caption>Example Fragment &ndash; Font Family</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="474px 146px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="center"/&gt;
-  &lt;style tts:textAlign="start"/&gt;
-  &lt;style <phrase role="strong">tts:fontFamily="proportionalSansSerif"</phrase>/&gt;
-&lt;/region&gt;
-...
-&lt;div region="r1"&gt;
-  &lt;p&gt;
-    "The time has come," the Walrus said,&lt;br/&gt;
-    "to talk of many things:
-  &lt;/p&gt;
-  &lt;p tts:textAlign="end" <phrase role="strong">tts:fontFamily="monospaceSerif"</phrase>&gt;
-    Of shoes, and ships, and sealing wax,&lt;br/&gt;
-    Of cabbages and kings,
-  &lt;/p&gt;
-  &lt;p&gt;
-    And why the sea is boiling hot,&lt;br/&gt;
-    and whether pigs have wings."
-  &lt;/p&gt;
-&lt;/div&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-fontFamily-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Font Family</caption>
-<tbody>
-<tr>
-<td><graphic source="images/fontFamily.png" alt="TTML fontFamily style property"/></td>
-</tr>
-</tbody>
-</table>
-<!--CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.9.2.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-fontSize">
-<head>tts:fontSize</head>
-<p>The <att>tts:fontSize</att> attribute is used to specify a style property
-that defines the font size for glyphs that are selected for glyph areas
-generated by content flowed into a region, where font size is interpreted as a
-scaling transform to the font's design EM square.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-fontSize" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<loc href="#style-value-length">&lt;length&gt;</loc> <loc href="#style-value-length">&lt;length&gt;</loc>?
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>1c</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>yes</td>
-</tr>
-<tr>
-<td><emph>Percentages:</emph></td>
-<td>relative to parent element's font size</td>
-</tr>
-<tr>
-<td><emph>Animatable:</emph></td>
-<td>discrete</td>
-</tr>
-</tbody>
-</table>
-<p>If a single <loc href="#style-value-length">&lt;length&gt;</loc> value is specified, then this length applies
-equally to horizontal and vertical scaling of a glyph's EM square; if two
-<loc href="#style-value-length">&lt;length&gt;</loc> values are specified, then the first expresses the horizontal
-scaling and the second expresses vertical scaling.</p>
-<note role="example">
-<p>Use of independent horizontal and vertical font sizes is expected to be used
-with cell based metrics in order to denote fonts that are two rows in height and
-one column in width.</p>
-</note>
-<p>If horizontal and vertical sizes are expressed independently, then the
-metrics of the <loc href="#style-value-length">&lt;length&gt;</loc> values must be the same.</p>
-<p>The <loc href="#style-value-length">&lt;length&gt;</loc> value(s) used to express font size must be non-negative.</p>
-<p>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>1c</code> were specified.</p>
-<note role="elaboration">
-<p>The expression <code>1c</code> means one cell, where <code>'c'</code> expresses
-the <emph>cell</emph> length unit as defined by <specref ref="style-value-length"/>.</p>
-</note>
-<p>The <att>tts:fontSize</att> style is illustrated by the following example.</p>
-<table id="style-attribute-fontSize-example-1" role="example">
-<caption>Example Fragment &ndash; Font Size</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="299px 97px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="center"/&gt;
-  &lt;style tts:textAlign="center"/&gt;
-  &lt;style tts:fontFamily="proportionalSansSerif"/&gt;
-  &lt;style <phrase role="strong">tts:fontSize="18px"</phrase>/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  Then fill up the glasses&lt;br/&gt;
-  with treacle and ink,&lt;br/&gt;
-  Or anything else&lt;br/&gt;
-  that is &lt;span <phrase role="strong">tts:fontSize="24px"</phrase>&gt;pleasant&lt;/span&gt; to drink.
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-fontSize-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Font Size</caption>
-<tbody>
-<tr>
-<td><graphic source="images/fontSize.png" alt="TTML fontSize style property"/></td>
-</tr>
-</tbody>
-</table>
-<!--CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.9.4.</p>
-</note>
--->  
-</div3>
-<div3 id="style-attribute-fontStyle">
-<head>tts:fontStyle</head>
-<p>The <att>tts:fontStyle</att> attribute is used to specify a style property that
-defines the font style to apply to glyphs that are selected for glyph areas generated
-by content flowed into a region, where the mapping from font
-style value to specific font face or style parameterization is not determined
-by this specification.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-fontStyle" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>normal</code> |
-<code>italic</code> |
-<code>oblique</code> |
-<code>reverseOblique</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>normal</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>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>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>Use of values <code>oblique</code> and <code>reverseOblique</code>
-denote a shear and reverse shear transformation (at an unspecified
-angle) in the inline progression dimension.</p>
-<p>If a specified font style is not available, then a
-presentation processor must attempt to map the specified font style
-to an available font style that has similar typographic
-characteristics, or, in the absence of such a mapping, it must
-interpret the font style as if the value <code>normal</code> were
-specified.</p>
-<p>The <att>tts:fontStyle</att> style is illustrated by the following example.</p>
-<table id="style-attribute-fontStyle-example-1" role="example">
-<caption>Example Fragment &ndash; Font Style</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="331px 84px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="after"/&gt;
-  &lt;style tts:textAlign="center"/&gt;
-  &lt;style tts:fontFamily="proportionalSansSerif"/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  In autumn, when the leaves are brown,&lt;br/&gt;
-  Take pen and ink, and &lt;span <phrase role="strong">tts:fontStyle="italic"</phrase>&gt;write it down.&lt;/span&gt;
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-fontStyle-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Font Style</caption>
-<tbody>
-<tr>
-<td><graphic source="images/fontStyle.png" alt="TTML fontStyle style property"/></td>
-</tr>
-</tbody>
-</table>
-<p/>
-<!-- CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.9.7.</p>
-</note>
--->  
-</div3>
-<div3 id="style-attribute-fontWeight">
-<head>tts:fontWeight</head>
-<p>The <att>tts:fontWeight</att> attribute is used to specify a style property
-that defines the font weight to apply to glyphs that are selected for glyph
-areas generated by content flowed into a region, where the mapping from font
-weight value to specific font face or weight parameterization is not determined
-by this specification.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-fontWeight" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>normal</code> |
-<code>bold</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>normal</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>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>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>If a specified font weight is not available, then a
-presentation processor must attempt to map the specified font weight
-to an available font weight that has similar typographic
-characteristics, or, in the absence of such a mapping, it must
-interpret the font weight as if the value <code>normal</code> were
-specified.</p>
-<p>The <att>tts:fontWeight</att> style is illustrated by the following example.</p>
-<table id="style-attribute-fontWeight-example-1" role="example">
-<caption>Example Fragment &ndash; Font Weight</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="376px 95px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="center"/&gt;
-  &lt;style tts:textAlign="center"/&gt;
-  &lt;style tts:fontFamily="proportionalSansSerif"/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  They told me you had been to her,&lt;br/&gt;
-  &lt;span <phrase role="strong">tts:fontWeight="bold"</phrase>&gt;and mentioned me to him:&lt;/span&gt;&lt;br/&gt;
-  She gave me a good character&lt;br/&gt;
-  &lt;span <phrase role="strong">tts:fontWeight="bold"</phrase>&gt;but said I could not swim.&lt;/span&gt;
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-fontWeight-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Font Weight</caption>
-<tbody>
-<tr>
-<td><graphic source="images/fontWeight.png" alt="TTML fontWeight style property"/></td>
-</tr>
-</tbody>
-</table>
-<!--CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.9.9.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-lineHeight">
-<head>tts:lineHeight</head>
-<p>The <att>tts:lineHeight</att> attribute is used to specify a style property that
-defines the inter-baseline separation between line areas generated by content flowed into a region.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-lineHeight" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>normal</code> |
-<loc href="#style-value-length">&lt;length&gt;</loc>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>normal</code></td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#content-vocabulary-p"><el>p</el></loc>
-</td>
-</tr>
-<tr>
-<td><emph>Inherited:</emph></td>
-<td>yes</td>
-</tr>
-<tr>
-<td><emph>Percentages:</emph></td>
-<td>relative to this element's font size</td>
-</tr>
-<tr>
-<td><emph>Animatable:</emph></td>
-<td>discrete</td>
-</tr>
-</tbody>
-</table>
-<p>If the value of this attribute is <code>normal</code>, then the
-initial value of the style property must be considered to be the same
-as the largest font size that applies to any
-descendant element.</p>
-<p>If specified as a <loc
-href="#style-value-length">&lt;length&gt;</loc>, then the length must
-be non-negative.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>normal</code> were specified.</p>
-<p>The <att>tts:lineHeight</att> style is illustrated by the following example.</p>
-<table id="style-attribute-lineHeight-example-1" role="example">
-<caption>Example Fragment &ndash; Line Height</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="255px 190px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="center"/&gt;
-  &lt;style tts:textAlign="start"/&gt;
-  &lt;style tts:fontFamily="proportionalSansSerif"/&gt;
-  &lt;style tts:fontSize="16px"/&gt;
-  &lt;style <phrase role="strong">tts:lineHeight="32px"</phrase>/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  He thought he saw an elephant,&lt;br/&gt;
-  That practised on a fife:&lt;br/&gt;
-  He looked again, and found it was&lt;br/&gt;
-  A letter from his wife.&lt;br/&gt;
-  "At length I realise," he said,&lt;br/&gt;
-  "The bitterness of Life.
-"&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-lineHeight-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Line Height</caption>
-<tbody>
-<tr>
-<td><graphic source="images/lineHeight.png" alt="TTML lineHeight style property"/></td>
-</tr>
-</tbody>
-</table>
-<p/>
-<!-- CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.16.4.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-opacity">
-<head>tts:opacity</head>
-<p>The <att>tts:opacity</att> attribute is used to specify a style property that
-defines the opacity (or conversely, the transparency)
-of marks associated with a region.</p>
-<p>When presented onto a visual medium, the opacity of the region is applied uniformly and on a linear scale
-to all marks produced by content targeted to the
-region.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-opacity" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<loc href="#style-value-alpha">&lt;alpha&gt;</loc>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td>
-<code>1.0</code>
-</td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#layout-vocabulary-region"><el>region</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>An <loc href="#style-value-alpha">&lt;alpha&gt;</loc> value greater
-than 1.0 must be considered equivalent to an <loc
-href="#style-value-alpha">&lt;alpha&gt;</loc> value of 1.0.</p>
-<p>The <att>tts:opacity</att> style is illustrated by the following example.</p>
-<table id="style-attribute-opacity-example-1" role="example">
-<caption>Example Fragment &ndash; Opacity</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1" dur="5s"&gt;
-  &lt;set begin="0s" dur="1s" <phrase role="strong">tts:opacity="1.00"</phrase>/&gt;
-  &lt;set begin="1s" dur="1s" <phrase role="strong">tts:opacity="0.75"</phrase>/&gt;
-  &lt;set begin="2s" dur="1s" <phrase role="strong">tts:opacity="0.50"</phrase>/&gt;
-  &lt;set begin="3s" dur="1s" <phrase role="strong">tts:opacity="0.25"</phrase>/&gt;
-  &lt;set begin="4s" dur="1s" <phrase role="strong">tts:opacity="0.00"</phrase>/&gt;
-  &lt;style tts:extent="304px 77px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="after"/&gt;
-  &lt;style tts:textAlign="center"/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  The sun was shining on the sea
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-opacity-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Opacity</caption>
-<tbody>
-<tr>
-<td>
-<graphic source="images/opacity_0.png" alt="TTML opacity style property - [0,1)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/opacity_1.png" alt="TTML opacity style property - [1,2)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/opacity_2.png" alt="TTML opacity style property - [2,3)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/opacity_3.png" alt="TTML opacity style property - [3,4)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/opacity_4.png" alt="TTML opacity style property - [4,5)"/>
-</td>
-</tr>
-</tbody>
-</table>
-<!--CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="css3-color"/>,
-&sect; 3.2.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-origin">
-<head>tts:origin</head>
-<p>The <att>tts:origin</att> attribute is used to specify the
-<emph>x</emph> and <emph>y</emph> coordinates of the origin of a
-region area with respect to the origin of the root container extent,
-if specified, or the external authoring context, if not specified.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-origin" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>auto</code> |
-<loc href="#style-value-length">&lt;length&gt;</loc> <loc href="#style-value-length">&lt;length&gt;</loc>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>auto</code></td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#layout-vocabulary-region"><el>region</el></loc>
-</td>
-</tr>
-<tr>
-<td><emph>Inherited:</emph></td>
-<td>no</td>
-</tr>
-<tr>
-<td><emph>Percentages:</emph></td>
-<td>relative to width and height of root container region</td>
-</tr>
-<tr>
-<td><emph>Animatable:</emph></td>
-<td>discrete</td>
-</tr>
-</tbody>
-</table>
-<p>If the value of this attribute consists of two <loc href="#style-value-length">&lt;length&gt;</loc> specifications,
-then they must be interpreted as <emph>x</emph> and <emph>y</emph> coordinates, where the first specification
-is the <emph>x</emph> coordinate, and the second specification is the <emph>y</emph> coordinate.</p>
-<p>If the value of this attribute is <code>auto</code>, then the initial value
-of the style property must be considered to be the same as the root container
-origin.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>auto</code> were specified.</p>
-<p>The <att>tts:origin</att> style is illustrated by the following example.</p>
-<table id="style-attribute-origin-example-1" role="example">
-<caption>Example Fragment &ndash; Origin</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style <phrase role="strong">tts:origin="40px 40px"</phrase>/&gt;
-  &lt;style tts:extent="308px 92px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="center"/&gt;
-  &lt;style tts:textAlign="center"/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  "To dine!" she shrieked in dragon-wrath.&lt;br/&gt;
-  "To swallow wines all foam and froth!&lt;br/&gt;
-   To simper at a table-cloth!"
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-origin-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Origin</caption>
-<tbody>
-<tr>
-<td><graphic source="images/origin.png" alt="TTML origin style property"/></td>
-</tr>
-</tbody>
-</table>
-</div3>
-<div3 id="style-attribute-overflow">
-<head>tts:overflow</head>
-<p>The <att>tts:overflow</att> attribute is used to specify a style property that
-defines whether a region area is clipped or not if the descendant areas of the region overflow
-its extent.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-overflow" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>visible</code> |
-<code>hidden</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>hidden</code></td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#layout-vocabulary-region"><el>region</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>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
-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>
-</note>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>hidden</code> were specified.</p>
-<p>The <att>tts:overflow</att> style is illustrated by the following example.</p>
-<table id="style-attribute-overflow-example-1" role="example">
-<caption>Example Fragment &ndash; Overflow</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="232px 40px"/&gt;
-  &lt;style tts:origin="0px 0px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="red"/&gt;
-  &lt;style tts:displayAlign="before"/&gt;
-  &lt;style tts:textAlign="start"/&gt;
-  &lt;style tts:fontFamily="proportionalSansSerif"/&gt;
-  &lt;style tts:fontSize="18px"/&gt;
-  &lt;style tts:wrapOption="noWrap"/&gt;
-  &lt;style <phrase role="strong">tts:overflow="visible"</phrase>/&gt;
-&lt;/region&gt;
-&lt;region xml:id="r2"&gt;
-  &lt;style tts:extent="232px 40px"/&gt;
-  &lt;style tts:origin="0px 43px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="red"/&gt;
-  &lt;style tts:displayAlign="before"/&gt;
-  &lt;style tts:textAlign="start"/&gt;
-  &lt;style tts:fontFamily="proportionalSansSerif"/&gt;
-  &lt;style tts:fontSize="18px"/&gt;
-  &lt;style tts:wrapOption="noWrap"/&gt;
-  &lt;style <phrase role="strong">tts:overflow="hidden"</phrase>/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  "But wait a bit," the Oysters cried,&lt;br/&gt;
-  "Before we have our chat;
-&lt;/p&gt;
-&lt;p region="r2"&gt;
-  For some of us are out of breath,&lt;br/&gt;
-  And all of us are fat!"
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-overflow-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Overflow</caption>
-<tbody>
-<tr>
-<td><graphic source="images/overflow.png" alt="TTML overflow style property"/></td>
-</tr>
-</tbody>
-</table>
-<note role="explanation">
-<p>In the above example, the <att>tts:noWrap</att> is set to
-<code>noWrap</code> to prevent automatic line wrapping (breaking);
-if this were not specified, then overflow would occur in the block
-progression direction as opposed to the inline progression direction.</p>
-</note>
-<!-- CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.21.2.</p>
-</note>
--->  
-</div3>
-<div3 id="style-attribute-padding">
-<head>tts:padding</head>
-<p>The <att>tts:padding</att> attribute is used to specify padding (or inset)
-space on all sides of a region area.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-padding" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<loc href="#style-value-length">&lt;length&gt;</loc> |
-<loc href="#style-value-length">&lt;length&gt;</loc> <loc href="#style-value-length">&lt;length&gt;</loc> |
-<loc href="#style-value-length">&lt;length&gt;</loc> <loc href="#style-value-length">&lt;length&gt;</loc> <loc href="#style-value-length">&lt;length&gt;</loc> |
-<loc href="#style-value-length">&lt;length&gt;</loc> <loc href="#style-value-length">&lt;length&gt;</loc> <loc href="#style-value-length">&lt;length&gt;</loc> <loc href="#style-value-length">&lt;length&gt;</loc>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>0px</code></td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#layout-vocabulary-region"><el>region</el></loc>
-</td>
-</tr>
-<tr>
-<td><emph>Inherited:</emph></td>
-<td>no</td>
-</tr>
-<tr>
-<td><emph>Percentages:</emph></td>
-<td>relative to width and height of region</td>
-</tr>
-<tr>
-<td><emph>Animatable:</emph></td>
-<td>discrete</td>
-</tr>
-</tbody>
-</table>
-<p>If the value of this attribute consists of one <loc href="#style-value-length">&lt;length&gt;</loc> specification,
-then that length applies to all edges of the affected areas. If the value
-consists of two <loc href="#style-value-length">&lt;length&gt;</loc> specifications, then the first applies to the
-before and after edges, and the second applies to the start and end edges.
-If three <loc href="#style-value-length">&lt;length&gt;</loc> specifications are provided, then the first applies to the
-before edge, the second applies to the start and end edges, and the third applies
-to the after edge.
-If four <loc href="#style-value-length">&lt;length&gt;</loc> specifications are provided, then they apply to before, end,
-after, and start edges, respectively.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>0px</code> were specified.</p>
-<p>The <att>tts:padding</att> style is illustrated by the following example.</p>
-<table id="style-attribute-padding-example-1" role="example">
-<caption>Example Fragment &ndash; Padding</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="446px 104px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="after"/&gt;
-  &lt;style tts:textAlign="center"/&gt;
-  &lt;style <phrase role="strong">tts:padding="10px 40px"</phrase>/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1" tts:backgroundColor="red"&gt;
-  Just the place for a Snark! I have said it twice:&lt;br/&gt;
-  That alone should encourage the crew.&lt;br/&gt;
-  Just the place for a Snark! I have said it thrice:&lt;br/&gt;
-  What I tell you three times is true.
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p>When rendering an area to which padding applies, the background color that
-applies to the area is rendered into the padded portion of the area.</p>
-<table id="style-attribute-padding-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Padding</caption>
-<tbody>
-<tr>
-<td>
-<graphic source="images/padding.png" alt="TTML padding style property"/>
-</td>
-</tr>
-</tbody>
-</table>
- <!-- CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.31.15, except that individual shorthand values map to writing
-  mode relative padding values as defined by <bibref ref="xsl11"/>,
-&sect; 7.8.31, 7.8.32, 7.8.33, and 7.8.34.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-showBackground">
-<head>tts:showBackground</head>
-<p>The <att>tts:showBackground</att> attribute is used to specify
-constraints on when the background color of a region is intended to be
-presented.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-showBackground" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>always</code> |
-<code>whenActive</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>always</code></td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#layout-vocabulary-region"><el>region</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>If the value of this attribute is <code>always</code>, then the
-background color of a region is always rendered when performing presentation
-processing on a visual medium; if the value is <code>whenActive</code>,
-then the background color of a region is rendered only when some
-content is selected into the region.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>always</code> were specified.</p>
-<p>The <att>tts:showBackground</att> style is illustrated by the following example.</p>
-<table id="style-attribute-showBackground-example-1" role="example">
-<caption>Example Fragment &ndash; Show Background</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:origin="0px 0px"/&gt;
-  &lt;style tts:extent="265px 100px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style <phrase role="strong">tts:showBackground="always"</phrase>/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="before"/&gt;
-  &lt;style tts:textAlign="start"/&gt;
-&lt;/region&gt;
-&lt;region xml:id="r2"&gt;
-  &lt;style tts:origin="205px 60px"/&gt;
-  &lt;style tts:extent="290px 100px"/&gt;
-  &lt;style tts:backgroundColor="red"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="before"/&gt;
-  &lt;style tts:textAlign="end"/&gt;
-  &lt;style <phrase role="strong">tts:showBackground="whenActive"</phrase>/&gt;
-&lt;/region&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<!--
-<table id="style-attribute-showBackground-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Show Background</caption>
-<tbody>
-<tr>
-<td>
-<graphic source="images/showBackground.png" alt="TTML showBackground style property"/>
-</td>
-</tr>
-</tbody>
-</table>
--->
-<!-- CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="smil21"/>,
-&sect; 5.3.1.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-textAlign">
-<head>tts:textAlign</head>
-<p>The <att>tts:textAlign</att> attribute is used to specify a style property that
-defines how inline areas are aligned within a containing block area in the inline progression
-direction.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-textAlign" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>left</code> |
-<code>center</code> |
-<code>right</code> |
-<code>start</code> |
-<code>end</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>start</code></td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#content-vocabulary-p"><el>p</el></loc>
-</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>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>start</code> were specified.</p>
-<p>The <att>tts:textAlign</att> style is illustrated by the following example.</p>
-<table id="style-attribute-textAlign-example-1" role="example">
-<caption>Example Fragment &ndash; Text Align</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="355px 43px"/&gt;
-  &lt;style tts:origin="0px 0px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style <phrase role="strong">tts:textAlign="start"</phrase>/&gt;
-&lt;/region&gt;
-&lt;region xml:id="r2"&gt;
-  &lt;style tts:extent="355px 43px"/&gt;
-  &lt;style tts:origin="0px 47px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style <phrase role="strong">tts:textAlign="end"</phrase>/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  Beware the Jabberwock, my son!&lt;br/&gt;
-  The jaws that bite, the claws that catch!
-&lt;/p&gt;
-&lt;p region="r2"&gt;
-  Beware the Jubjub bird, and shun&lt;br/&gt;
-  The frumious Bandersnatch!
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-textAlign-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Text Align</caption>
-<tbody>
-<tr>
-<td><graphic source="images/textAlign.png" alt="TTML textAlign style property"/></td>
-</tr>
-</tbody>
-</table>
-<!--CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.16.9.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-textDecoration">
-<head>tts:textDecoration</head>
-<p>The <att>tts:textDecoration</att> attribute is used to specify a style property that
-defines a text decoration effect to apply to glyph areas or other inline
-areas that are generated by content flowed into a region.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-textDecoration" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>none</code> |
-[ [
-<code>underline</code> |
-<code>noUnderline</code>
-] || [
-<code>lineThrough</code> |
-<code>noLineThrough</code>
-] || [
-<code>overline</code> |
-<code>noOverline</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>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>For the purpose of determining applicability of this
-style property, each character child of a <el>p</el> element is
-considered to be enclosed in an anonymous span.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>none</code> were specified.</p>
-<p>The <att>tts:textDecoration</att> style is illustrated by the following example.</p>
-<table id="style-attribute-textDecoration-example-1" role="example">
-<caption>Example Fragment &ndash; Text Decoration</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="385px 82px"/&gt;
-  &lt;style tts:origin="0px 0px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:padding="5px 2px"/&gt;
-  &lt;style <phrase role="strong">tts:textDecoration="underline"</phrase>/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  The sea was wet&lt;span <phrase role="strong">tts:textDecoration="noUnderline"</phrase>&gt; as &lt;/span&gt;wet
-  &lt;span <phrase role="strong">tts:textDecoration="noUnderline"</phrase>&gt;
-    could be,&lt;br/&gt;
-    The sand was dry as dry.&lt;br/&gt;
-    &lt;span <phrase role="strong">tts:textDecoration="lineThrough"</phrase>&gt;There weren't any&lt;/span&gt;
-    You &lt;span <phrase role="strong">tts:textDecoration="lineThrough"</phrase>&gt;couldn't&lt;/span&gt;
-    could not see a cloud&lt;br/&gt;
-    Because no cloud was in the sky.
-  &lt;/span&gt;
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-textDecoration-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Text Decoration</caption>
-<tbody>
-<tr>
-<td><graphic source="images/textDecoration.png" alt="TTML textDecoration style property"/></td>
-</tr>
-</tbody>
-</table>
-<!--CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.16.4.</p>
-</note>
--->  
-</div3>
-<div3 id="style-attribute-textOutline">
-<head>tts:textOutline</head>
-<p>The <att>tts:textOutline</att> attribute is used to specify a style property that
-defines a text outline effect to apply to glyphs that are selected for glyph areas generated
-by content flowed into a region.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-textOutline" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>none</code> |
-<loc href="#style-value-color">&lt;color&gt;</loc>?
-<loc href="#style-value-length">&lt;length&gt;</loc>
-<loc href="#style-value-length">&lt;length&gt;</loc>?
-</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>yes</td>
-</tr>
-<tr>
-<td><emph>Percentages:</emph></td>
-<td>relative to this element's font size</td>
-</tr>
-<tr>
-<td><emph>Animatable:</emph></td>
-<td>discrete</td>
-</tr>
-</tbody>
-</table>
-<p>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>The value of this attribute consists of an optional <loc href="#style-value-color">&lt;color&gt;</loc> term
-followed by one or two <loc href="#style-value-length">&lt;length&gt;</loc> terms.  If a <emph>color</emph> term is
-present, then it denotes the outline color; if no <emph>color</emph> term is
-present, the computed value of the <att>tts:color</att> applies.  The first
-<emph>length</emph> term denotes the outline thickness and the second length
-term, if present, indicates the blur radius.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>none</code> were specified.</p>
-<p>The <att>tts:textOutline</att> style is illustrated by the following
-example.</p>
-<table id="style-attribute-textOutline-example-1" role="example">
-<caption>Example Fragment &ndash; Text Outline</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:backgroundColor="transparent"/&gt;
-  &lt;style tts:color="yellow"/&gt;
-  &lt;style <phrase role="strong">tts:textOutline="black 2px 0px"</phrase>/&gt;
-  &lt;style tts:fontFamily="proportionalSansSerif"/&gt;
-  &lt;style tts:fontSize="24px"/&gt;
-&lt;/region&gt;
-...
-&lt;p&gt;
-  How doth the little crocodile&lt;br/&gt;
-  Improve its shining tail,&lt;br/&gt;
-  And pour the waters of the Nile&lt;br/&gt;
-  On every golden scale!&lt;br/&gt;
-  How cheerfully he seems to grin,&lt;br/&gt;
-  How neatly spreads his claws,&lt;br/&gt;
-  And welcomes little fishes in,&lt;br/&gt;
-  With gently smiling jaws!
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-textOutline-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Text Outline</caption>
-<tbody>
-<tr>
-<td><graphic source="images/textOutline.png" alt="backgroundColor style property"/></td>
-</tr>
-</tbody>
-</table>
-</div3>
-<div3 id="style-attribute-unicodeBidi">
-<head>tts:unicodeBidi</head>
-<p>The <att>tts:unicodeBidi</att> attribute is used to specify a style property that
-defines a directional embedding or override according to
-the Unicode bidirectional algorithm.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-unicodeBidi" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>normal</code> |
-<code>embed</code> |
-<code>bidiOverride</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td>
-<code>normal</code>
-</td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#content-vocabulary-p"><el>p</el></loc>,
-<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>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>normal</code> were specified.</p>
-<p>The <att>tts:unicodeBidi</att> style is illustrated by the following example.</p>
-<table id="style-attribute-unicodeBidi-example-1" role="example">
-<caption>Example Fragment &ndash; Unicode Bidirectionality</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="265px 84px"/&gt;
-  &lt;style tts:padding="5px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="after"/&gt;
-  &lt;style tts:textAlign="center"/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  Little birds are playing&lt;br/&gt;
-  Bagpipes on the shore,&lt;br/&gt;
-  &lt;span <phrase role="strong">tts:unicodeBidi="bidiOverride"</phrase> tts:direction="rtl"&gt;where the tourists snore.&lt;/span&gt;
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-unicodeBidi-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Unicode Bidirectionality</caption>
-<tbody>
-<tr>
-<td>
-<graphic source="images/unicodeBidi.png" alt="TTML unicodeBidi style property"/>
-</td>
-</tr>
-</tbody>
-</table>
-<!-- CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.29.6.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-visibility">
-<head>tts:visibility</head>
-<p>The <att>tts:visibility</att> attribute is used to specify a style property that
-defines whether generated areas are visible or not when rendered on a visual
-presentation medium.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-visibility" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>visible</code> |
-<code>hidden</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td>
-<code>visible</code>
-</td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#document-structure-vocabulary-body"><el>body</el></loc>,
-<loc href="#content-vocabulary-div"><el>div</el></loc>,
-<loc href="#content-vocabulary-p"><el>p</el></loc>,
-<loc href="#layout-vocabulary-region"><el>region</el></loc>,
-<loc href="#content-vocabulary-span"><el>span</el></loc>
-</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>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>The <att>tts:visibility</att> style has no affect on content layout or
-composition, but merely determines whether composed content is visible or not.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>visible</code> were specified.</p>
-<p>The <att>tts:visibility</att> style is illustrated by the following example.</p>
-<table id="style-attribute-visibility-example-1" role="example">
-<caption>Example Fragment &ndash; Visibility</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="398px 121px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1" dur="4s"&gt;
-  &lt;span <phrase role="strong">tts:visibility="hidden"</phrase>&gt;
-    &lt;set begin="1s" <phrase role="strong">tts:visibility="visible"</phrase>/&gt;
-    Curiouser
-  &lt;/span&gt;
-  &lt;span <phrase role="strong">tts:visibility="hidden"</phrase>&gt;
-    &lt;set begin="2s" <phrase role="strong">tts:visibility="visible"</phrase>/&gt;
-    and
-  &lt;/span&gt;
-  &lt;span <phrase role="strong">tts:visibility="hidden"</phrase>&gt;
-    &lt;set begin="3s" <phrase role="strong">tts:visibility="visible"</phrase>/&gt;
-    curiouser!
-  &lt;/span&gt;
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-visibility-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Visibility</caption>
-<tbody>
-<tr>
-<td>
-<graphic source="images/visibility_0.png" alt="TTML visibility style property - [0,1)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/visibility_1.png" alt="TTML visibility style property - [1,2)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/visibility_2.png" alt="TTML visibility style property - [2,3)"/>
-</td>
-</tr>
-<tr>
-<td>
-<graphic source="images/visibility_3.png" alt="TTML visibility style property - [3,4)"/>
-</td>
-</tr>
-</tbody>
-</table>
-<!-- CSS compatibility - remove derivation note
-  <note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.28.8.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-wrapOption">
-<head>tts:wrapOption</head>
-<p>The <att>tts:wrapOption</att> attribute is used to specify a style property that
-defines whether or not automatic line wrapping (breaking) applies within the context of
-the affected element.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-wrapOption" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>wrap</code> |
-<code>noWrap</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>wrap</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>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>For the purpose of determining applicability of this style property,
-each character child of a <el>p</el> element is considered to be enclosed in an anonymous
-span.</p>
-<p>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>wrap</code> were specified.</p>
-<p>The <att>tts:wrapOption</att> style is illustrated by the following example.</p>
-<table id="style-attribute-wrapOption-example-1" role="example">
-<caption>Example Fragment &ndash; Wrap Option</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="192px 117px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style tts:displayAlign="after"/&gt;
-  &lt;style tts:overflow="hidden"/&gt;
-  &lt;style <phrase role="strong">tts:wrapOption="noWrap"</phrase>/&gt;
-&lt;/region&gt;
-...
-&lt;p&gt;
-  I'll tell thee everything I can:&lt;br/&gt;
-  There's little to relate.&lt;br/&gt;
-  I saw an aged aged man,&lt;br/&gt;
-  A-sitting on a gate.
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-wrapOption-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Wrap Option</caption>
-<tbody>
-<tr>
-<td><graphic source="images/wrapOption.png" alt="TTML wrapOption style property"/></td>
-</tr>
-</tbody>
-</table>
-  <!-- CSS compatibility - remove derivation note
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.15.13.</p>
-</note>
--->
-</div3>
-<div3 id="style-attribute-writingMode">
-<head>tts:writingMode</head>
-<p>The <att>tts:writingMode</att> attribute is used to specify a style property that
-defines the block and inline progression directions to be used for the purpose of
-stacking block and inline areas within a region area.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-writingMode" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>lrtb</code> |
-<code>rltb</code> |
-<code>tbrl</code> |
-<code>tblr</code> |
-<code>lr</code> |
-<code>rl</code> |
-<code>tb</code>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>lrtb</code></td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#layout-vocabulary-region"><el>region</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>If a specified value of this attribute is not supported,
-then a presentation processor must interpret the attribute as if the
-value <code>lrtb</code> were specified.</p>
-<p>The <att>tts:writingMode</att> style is illustrated by the following example.</p>
-<table id="style-attribute-writingMode-example-1" role="example">
-<caption>Example Fragment &ndash; Writing Mode</caption>
-<tbody>
-<tr>
-<td>
-<eg xml:space="preserve">
-&lt;region xml:id="r1"&gt;
-  &lt;style tts:extent="50px 570px"/&gt;
-  &lt;style tts:origin="0px 0px"/&gt;
-  &lt;style tts:padding="10px 3px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style <phrase role="strong">tts:writingMode="tbrl"</phrase>/&gt;
-&lt;/region&gt;
-&lt;region xml:id="r2"&gt;
-  &lt;style tts:extent="310px 50px"/&gt;
-  &lt;style tts:origin="70px 120px"/&gt;
-  &lt;style tts:padding="10px 3px"/&gt;
-  &lt;style tts:backgroundColor="black"/&gt;
-  &lt;style tts:color="white"/&gt;
-  &lt;style <phrase role="strong">tts:writingMode="rltb"</phrase>/&gt;
-&lt;/region&gt;
-...
-&lt;p region="r1"&gt;
-  I sometimes dig for buttered rolls,&lt;br/&gt;
-  Or set limed twigs for crabs:
-&lt;/p&gt;
-&lt;p region="r2" tts:direction="rtl" tts:unicodeBidi="bidiOverride"&gt;
-  I sometimes search the grassy knolls for the wheels of Hansom-cabs.
-&lt;/p&gt;
-</eg>
-</td>
-</tr>
-</tbody>
-</table>
-<p/>
-<table id="style-attribute-writingMode-example-1-images" role="example-images">
-<caption>Example Rendition &ndash; Writing Mode</caption>
-<tbody>
-<tr>
-<td><graphic source="images/writingMode.png" alt="TTML writingMode style property"/></td>
-</tr>
-</tbody>
-</table>
-<note role="explanation">
-<p>In the second paragraph in the above example that targets region
-<code>r2</code>, the <att>tts:unicodeBidi</att> and
-<att>tts:direction</att> properties are set to
-<code>bidiOverride</code> and <code>rtl</code>, respectively, in order
-to override the normally left-to-right directionality of characters in
-the Latin script.</p>
-</note>
-<!-- CSS compatibility - remove derivation note 
-<note role="derivation">
-<p>The semantics of the style property
-represented by this attribute are based upon that defined by <bibref ref="xsl11"/>,
-&sect; 7.27.7.</p>
-</note>
-  -->
-</div3>
-<div3 id="style-attribute-zIndex">
-<head>tts:zIndex</head>
-<p>The <att>tts:zIndex</att> attribute is used to specify a style property that
-defines the front-to-back ordering of region areas in the case that they overlap.</p>
-<p>This attribute may be specified by any
-element type
-that permits use of attributes in the TT Style Namespace; however, this attribute applies
-as a style property only to those element types indicated in the following table.</p>
-<table id="style-property-details-zIndex" role="common">
-<col width="25%"/>
-<tbody>
-<tr>
-<td><emph>Values:</emph></td>
-<td>
-<code>auto</code> |
-<loc href="#style-value-integer">&lt;integer&gt;</loc>
-</td>
-</tr>
-<tr>
-<td><emph>Initial:</emph></td>
-<td><code>auto</code></td>
-</tr>
-<tr>
-<td><emph>Applies to:</emph></td>
-<td>
-<loc href="#layout-vocabulary-region"><el>region</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>