Binary file ttml-ww-profiles/forced-example-figure-1.png has changed
--- a/ttml-ww-profiles/ttml-ww-profiles.html Fri Jul 11 18:43:53 2014 -0700
+++ b/ttml-ww-profiles/ttml-ww-profiles.html Wed Jul 16 20:33:21 2014 -0700
@@ -217,11 +217,11 @@
</p>
<h1 class="title p-name" id="title" property="dcterms:title">TTML Text and Image Profiles for Internet Media Subtitles and Captions 1.0</h1>
- <h2 property="dcterms:issued" datatype="xsd:dateTime" content="2014-07-12T08:41:32.000Z" id="w3c-first-public-working-draft-12-july-2014"><abbr title="World Wide Web Consortium">W3C</abbr> First Public Working Draft <time class="dt-published" datetime="2014-07-12">12 July 2014</time></h2>
+ <h2 property="dcterms:issued" datatype="xsd:dateTime" content="2014-07-17T10:31:07.000Z" id="w3c-first-public-working-draft-17-july-2014"><abbr title="World Wide Web Consortium">W3C</abbr> First Public Working Draft <time class="dt-published" datetime="2014-07-17">17 July 2014</time></h2>
<dl>
<dt>This version:</dt>
- <dd><a class="u-url" href="http://www.w3.org/TR/2014/WD-ttml-imsc1-20140712/">http://www.w3.org/TR/2014/WD-ttml-imsc1-20140712/</a></dd>
+ <dd><a class="u-url" href="http://www.w3.org/TR/2014/WD-ttml-imsc1-20140717/">http://www.w3.org/TR/2014/WD-ttml-imsc1-20140717/</a></dd>
<dt>Latest published version:</dt>
<dd><a href="http://www.w3.org/TR/ttml-imsc1/">http://www.w3.org/TR/ttml-imsc1/</a></dd>
@@ -342,7 +342,7 @@
-</section><section id="toc"><h2 class="introductory" aria-level="1" role="heading" id="h2_toc">Table of Contents</h2><ul class="toc" role="directory" id="respecContents"><li class="tocline"><a href="#scope" class="tocxref"><span class="secno">1. </span>Scope</a></li><li class="tocline"><a href="#conformance" class="tocxref"><span class="secno">2. </span>Conformance</a></li><li class="tocline"><a href="#profiles" class="tocxref"><span class="secno">3. </span>Profiles</a><ul class="toc"><li class="tocline"><a href="#general" class="tocxref"><span class="secno">3.1 </span>General</a></li><li class="tocline"><a href="#text-profile" class="tocxref"><span class="secno">3.2 </span>Text Profile</a></li><li class="tocline"><a href="#image-profile" class="tocxref"><span class="secno">3.3 </span>Image Profile</a></li></ul></li><li class="tocline"><a href="#common-constraints" class="tocxref"><span class="secno">4. </span>Common Constraints</a><ul class="toc"><li class="tocline"><a href="#document-encoding" class="tocxref"><span class="secno">4.1 </span>Document Encoding</a></li><li class="tocline"><a href="#namespaces" class="tocxref"><span class="secno">4.2 </span>Namespaces</a></li><li class="tocline"><a href="#related-video-object" class="tocxref"><span class="secno">4.3 </span>Related Video Object</a></li><li class="tocline"><a href="#synchronization" class="tocxref"><span class="secno">4.4 </span>Synchronization</a></li><li class="tocline"><a href="#extensions" class="tocxref"><span class="secno">4.5 </span>Extensions</a><ul class="toc"><li class="tocline"><a href="#ttp-aspectRatio" class="tocxref"><span class="secno">4.5.1 </span>ittp:aspectRatio</a></li><li class="tocline"><a href="#ttp-progressivelyDecodable" class="tocxref"><span class="secno">4.5.2 </span>ittp:progressivelyDecodable</a></li><li class="tocline"><a href="#tts-forcedDisplay" class="tocxref"><span class="secno">4.5.3 </span>itts:forcedDisplay</a></li><li class="tocline"><a href="#ttm-altText" class="tocxref"><span class="secno">4.5.4 </span>ittm:altText</a></li></ul></li><li class="tocline"><a href="#region" class="tocxref"><span class="secno">4.6 </span>Region</a><ul class="toc"><li class="tocline"><a href="#presented-region" class="tocxref"><span class="secno">4.6.1 </span>Presented Region</a></li><li class="tocline"><a href="#dimensions-and-position" class="tocxref"><span class="secno">4.6.2 </span>Dimensions and Position</a></li><li class="tocline"><a href="#maximum-number" class="tocxref"><span class="secno">4.6.3 </span>Maximum number</a></li></ul></li><li class="tocline"><a href="#hypothetical-render-model-1" class="tocxref"><span class="secno">4.7 </span>Hypothetical Render Model</a></li><li class="tocline"><a href="#common-features" class="tocxref"><span class="secno">4.8 </span>Features</a></li></ul></li><li class="tocline"><a href="#text-profile-constraints" class="tocxref"><span class="secno">5. </span>Text Profile Constraints</a><ul class="toc"><li class="tocline"><a href="#text-profile-designator" class="tocxref"><span class="secno">5.1 </span>Profile Designator</a></li><li class="tocline"><a href="#recommended-character-sets" class="tocxref"><span class="secno">5.2 </span>Recommended Character Sets</a></li><li class="tocline"><a href="#features" class="tocxref"><span class="secno">5.3 </span>Features</a></li></ul></li><li class="tocline"><a href="#image-profile-constraints" class="tocxref"><span class="secno">6. </span>Image Profile Constraints</a><ul class="toc"><li class="tocline"><a href="#image-profile-designator" class="tocxref"><span class="secno">6.1 </span>Profile Designator</a></li><li class="tocline"><a href="#presented-image" class="tocxref"><span class="secno">6.2 </span>Presented Image</a><ul class="toc"><li class="tocline"><a href="#definition" class="tocxref"><span class="secno">6.2.1 </span>Definition</a></li><li class="tocline"><a href="#number-per-region" class="tocxref"><span class="secno">6.2.2 </span>Number per Region</a></li></ul></li><li class="tocline"><a href="#div-element" class="tocxref"><span class="secno">6.3 </span><code>div</code> element</a></li><li class="tocline"><a href="#features-1" class="tocxref"><span class="secno">6.4 </span>Features</a></li></ul></li><li class="tocline"><a href="#hypothetical-render-model" class="tocxref"><span class="secno">7. </span>Hypothetical Render Model</a><ul class="toc"><li class="tocline"><a href="#performance-model" class="tocxref"><span class="secno">7.1 </span>Performance Model</a><ul class="toc"><li class="tocline"><a href="#overview" class="tocxref"><span class="secno">7.1.1 </span>Overview</a></li><li class="tocline"><a href="#general-1" class="tocxref"><span class="secno">7.1.2 </span>General</a></li><li class="tocline"><a href="#paint-regions" class="tocxref"><span class="secno">7.1.3 </span>Paint Regions</a></li><li class="tocline"><a href="#paint-images" class="tocxref"><span class="secno">7.1.4 </span>Paint Images</a></li><li class="tocline"><a href="#paint-text" class="tocxref"><span class="secno">7.1.5 </span>Paint Text</a></li></ul></li><li class="tocline"><a href="#reference-fonts" class="tocxref"><span class="secno">7.2 </span>Reference Fonts</a></li></ul></li><li class="tocline"><a href="#recommended-unicode-code-points-per-language" class="tocxref"><span class="secno">A. </span>Recommended Character Sets</a></li><li class="tocline"><a href="#wcag-applications" class="tocxref"><span class="secno">B. </span>WCAG Considerations</a></li><li class="tocline"><a href="#features-and-extensions" class="tocxref"><span class="secno">C. </span>Extensions</a><ul class="toc"><li class="tocline"><a href="#general-2" class="tocxref"><span class="secno">C.1 </span>General</a></li><li class="tocline"><a href="#progressivelydecodable" class="tocxref"><span class="secno">C.2 </span>#progressivelyDecodable</a></li><li class="tocline"><a href="#aspectratio" class="tocxref"><span class="secno">C.3 </span>#aspectRatio</a></li><li class="tocline"><a href="#forceddisplay" class="tocxref"><span class="secno">C.4 </span>#forcedDisplay</a></li></ul></li><li class="tocline"><a href="#alttext" class="tocxref"><span class="secno">D. </span>#altText</a></li><li class="tocline"><a href="#references" class="tocxref"><span class="secno">E. </span>References</a><ul class="toc"><li class="tocline"><a href="#normative-references" class="tocxref"><span class="secno">E.1 </span>Normative references</a></li><li class="tocline"><a href="#informative-references" class="tocxref"><span class="secno">E.2 </span>Informative references</a></li></ul></li></ul></section>
+</section><section id="toc"><h2 class="introductory" aria-level="1" role="heading" id="h2_toc">Table of Contents</h2><ul class="toc" role="directory" id="respecContents"><li class="tocline"><a href="#scope" class="tocxref"><span class="secno">1. </span>Scope</a></li><li class="tocline"><a href="#conformance" class="tocxref"><span class="secno">2. </span>Conformance</a></li><li class="tocline"><a href="#profiles" class="tocxref"><span class="secno">3. </span>Profiles</a><ul class="toc"><li class="tocline"><a href="#general" class="tocxref"><span class="secno">3.1 </span>General</a></li><li class="tocline"><a href="#text-profile" class="tocxref"><span class="secno">3.2 </span>Text Profile</a></li><li class="tocline"><a href="#image-profile" class="tocxref"><span class="secno">3.3 </span>Image Profile</a></li></ul></li><li class="tocline"><a href="#common-constraints" class="tocxref"><span class="secno">4. </span>Common Constraints</a><ul class="toc"><li class="tocline"><a href="#document-encoding" class="tocxref"><span class="secno">4.1 </span>Document Encoding</a></li><li class="tocline"><a href="#namespaces" class="tocxref"><span class="secno">4.2 </span>Namespaces</a></li><li class="tocline"><a href="#related-video-object" class="tocxref"><span class="secno">4.3 </span>Related Video Object</a></li><li class="tocline"><a href="#synchronization" class="tocxref"><span class="secno">4.4 </span>Synchronization</a></li><li class="tocline"><a href="#extensions" class="tocxref"><span class="secno">4.5 </span>Extensions</a><ul class="toc"><li class="tocline"><a href="#ttp-aspectRatio" class="tocxref"><span class="secno">4.5.1 </span>ittp:aspectRatio</a></li><li class="tocline"><a href="#ttp-progressivelyDecodable" class="tocxref"><span class="secno">4.5.2 </span>ittp:progressivelyDecodable</a></li><li class="tocline"><a href="#tts-forcedDisplay" class="tocxref"><span class="secno">4.5.3 </span>itts:forcedDisplay</a></li><li class="tocline"><a href="#ttm-altText" class="tocxref"><span class="secno">4.5.4 </span>ittm:altText</a></li></ul></li><li class="tocline"><a href="#region" class="tocxref"><span class="secno">4.6 </span>Region</a><ul class="toc"><li class="tocline"><a href="#presented-region" class="tocxref"><span class="secno">4.6.1 </span>Presented Region</a></li><li class="tocline"><a href="#dimensions-and-position" class="tocxref"><span class="secno">4.6.2 </span>Dimensions and Position</a></li><li class="tocline"><a href="#maximum-number" class="tocxref"><span class="secno">4.6.3 </span>Maximum number</a></li></ul></li><li class="tocline"><a href="#hypothetical-render-model-1" class="tocxref"><span class="secno">4.7 </span>Hypothetical Render Model</a></li><li class="tocline"><a href="#common-features" class="tocxref"><span class="secno">4.8 </span>Features</a></li></ul></li><li class="tocline"><a href="#text-profile-constraints" class="tocxref"><span class="secno">5. </span>Text Profile Constraints</a><ul class="toc"><li class="tocline"><a href="#text-profile-designator" class="tocxref"><span class="secno">5.1 </span>Profile Designator</a></li><li class="tocline"><a href="#recommended-character-sets" class="tocxref"><span class="secno">5.2 </span>Recommended Character Sets</a></li><li class="tocline"><a href="#features" class="tocxref"><span class="secno">5.3 </span>Features</a></li></ul></li><li class="tocline"><a href="#image-profile-constraints" class="tocxref"><span class="secno">6. </span>Image Profile Constraints</a><ul class="toc"><li class="tocline"><a href="#image-profile-designator" class="tocxref"><span class="secno">6.1 </span>Profile Designator</a></li><li class="tocline"><a href="#presented-image" class="tocxref"><span class="secno">6.2 </span>Presented Image</a><ul class="toc"><li class="tocline"><a href="#definition" class="tocxref"><span class="secno">6.2.1 </span>Definition</a></li><li class="tocline"><a href="#number-per-region" class="tocxref"><span class="secno">6.2.2 </span>Number per Region</a></li></ul></li><li class="tocline"><a href="#div-element" class="tocxref"><span class="secno">6.3 </span><code>div</code> element</a></li><li class="tocline"><a href="#features-1" class="tocxref"><span class="secno">6.4 </span>Features</a></li></ul></li><li class="tocline"><a href="#hypothetical-render-model" class="tocxref"><span class="secno">7. </span>Hypothetical Render Model</a><ul class="toc"><li class="tocline"><a href="#performance-model" class="tocxref"><span class="secno">7.1 </span>Performance Model</a><ul class="toc"><li class="tocline"><a href="#overview" class="tocxref"><span class="secno">7.1.1 </span>Overview</a></li><li class="tocline"><a href="#general-1" class="tocxref"><span class="secno">7.1.2 </span>General</a></li><li class="tocline"><a href="#paint-regions" class="tocxref"><span class="secno">7.1.3 </span>Paint Regions</a></li><li class="tocline"><a href="#paint-images" class="tocxref"><span class="secno">7.1.4 </span>Paint Images</a></li><li class="tocline"><a href="#paint-text" class="tocxref"><span class="secno">7.1.5 </span>Paint Text</a></li></ul></li><li class="tocline"><a href="#reference-fonts" class="tocxref"><span class="secno">7.2 </span>Reference Fonts</a></li></ul></li><li class="tocline"><a href="#recommended-unicode-code-points-per-language" class="tocxref"><span class="secno">A. </span>Recommended Character Sets</a></li><li class="tocline"><a href="#forced-content" class="tocxref"><span class="secno">B. </span>Forced content</a></li><li class="tocline"><a href="#wcag-applications" class="tocxref"><span class="secno">C. </span>WCAG Considerations</a></li><li class="tocline"><a href="#features-and-extensions" class="tocxref"><span class="secno">D. </span>Extensions</a><ul class="toc"><li class="tocline"><a href="#general-2" class="tocxref"><span class="secno">D.1 </span>General</a></li><li class="tocline"><a href="#progressivelydecodable" class="tocxref"><span class="secno">D.2 </span>#progressivelyDecodable</a></li><li class="tocline"><a href="#aspectratio" class="tocxref"><span class="secno">D.3 </span>#aspectRatio</a></li><li class="tocline"><a href="#forceddisplay" class="tocxref"><span class="secno">D.4 </span>#forcedDisplay</a></li></ul></li><li class="tocline"><a href="#alttext" class="tocxref"><span class="secno">E. </span>#altText</a></li><li class="tocline"><a href="#references" class="tocxref"><span class="secno">F. </span>References</a><ul class="toc"><li class="tocline"><a href="#normative-references" class="tocxref"><span class="secno">F.1 </span>Normative references</a></li><li class="tocline"><a href="#informative-references" class="tocxref"><span class="secno">F.2 </span>Informative references</a></li></ul></li></ul></section>
@@ -389,7 +389,7 @@
<div class="note"><div class="note-title" aria-level="3" role="heading" id="h_note_1"><span>Note</span></div><p class="">The <code>ittm:altText</code> element specified <a href="#ttm-altText" class="sec-ref"><span class="secno">4.5.4</span> <span class="sec-title">ittm:altText</span></a> also allows text equivalent string to be associated with an image, e.g. to support indexation of the content and also facilitate quality checking of the document during authoring.</p></div>
- <p>Annex <a href="#wcag-applications" class="sec-ref"><span class="secno">B.</span> <span class="sec-title">WCAG Considerations</span></a> specifically discusses this specification in the context of the [<cite><a class="bibref" href="#bib-WCAG20">WCAG20</a></cite>] guidelines.
+ <p>Annex <a href="#wcag-applications" class="sec-ref"><span class="secno">C.</span> <span class="sec-title">WCAG Considerations</span></a> specifically discusses this specification in the context of the [<cite><a class="bibref" href="#bib-WCAG20">WCAG20</a></cite>] guidelines.
</p></section>
@@ -676,16 +676,9 @@
<section id="tts-forcedDisplay" typeof="bibo:Chapter" resource="#tts-forcedDisplay" rel="bibo:Chapter">
<h4 aria-level="3" role="heading" id="h4_tts-forcedDisplay"><span class="secno">4.5.3 </span>itts:forcedDisplay</h4>
- <p><code>itts:forcedDisplay</code> identifies <em>Forced</em> subtitle content. <em>Forced</em> subtitle content is
- subtitle content that represents audio (e.g. foreign language) or text (e.g. a sign) that is not translated in the
- audio/video presentation, e.g. Na'vi language in the movie Avatar. As such <em>Forced</em> subtitle content is useful
- whether the user has explicitly requested subtitles to be displayed.</p>
-
- <p>When presenting a subtitle document, a presentation processor <em class="rfc2119" title="SHOULD">SHOULD</em> display content for which the computed value of
- <code>itts:forcedDisplay</code> is <code>true</code>, regardless of whether the user has explicitly requested display of
- subtitle content.</p>
-
- <table class="simple">
+ <p><code>itts:forcedDisplay</code> identifies forced content, which represents audio (e.g. foreign language) or text (e.g. a sign) that is not translated in the audio/video presentation. The presentation of elements based their computed <code>itts:forcedDisplay</code> value is controlled using the <code>displayForcedOnlyMode</code> application parameter. Annex <a href="#forced-content" class="sec-ref"><span class="secno">B.</span> <span class="sec-title">Forced content</span></a> illustrates the use of <code>itts:forcedDisplay</code>.</p>
+
+ <table class="simple">
<colgroup>
<col style="width:25%" span="1">
<col span="1">
@@ -730,15 +723,18 @@
</tbody>
</table>
- <div class="note"><div class="note-title" aria-level="4" role="heading" id="h_note_5"><span>Note</span></div><p class="">Although <code>itts:forcedDisplay</code>, like all the TTML style attributes, has no defined semantics on a
+ <p>The presentation processor <em class="rfc2119" title="SHALL">SHALL</em> accept an optional boolean parameter called <code>displayForcedOnlyMode</code>, whose value <em class="rfc2119" title="MAY">MAY</em> be set by the application. If not set, the value of <code>displayForcedOnlyMode</code> <em class="rfc2119" title="SHALL">SHALL</em> be assumed to be equal to "false".</p>
+
+ <p>If the value of <code>displayForcedOnlyMode</code> is "true", a content element with a <code>itts:forcedDisplay</code> computed value of "false" shall be assumed to have a <code>tts:visibility</code> computed value equal to "hidden", even if <code>tts:visibility</code> is otherwise set to "true".</p>
+
+ <div class="note"><div class="note-title" aria-level="4" role="heading" id="h_note_5"><span>Note</span></div><p class="">A region will remain visible even if all content elements have a computed <code>tts:visibility</code> value of "hidden" unless <code>tts:showBackground</code> is set to "whenActive" (the initial value of <code>tts:showBackground</code> is "always".)</p></div>
+
+ <div class="note"><div class="note-title" aria-level="4" role="heading" id="h_note_6"><span>Note</span></div><p class="">Although <code>itts:forcedDisplay</code>, like all the TTML style attributes, has no defined semantics on a
<code>br</code> content element, <code>itts:forcedDisplay</code> will apply to a <code>br</code> content element if it is
either defined on an ancestor content element of the <code>br</code> content element or it is applied to a region element
corresponding to a region that the <code>br</code> content element is being flowed into.</p></div>
- <div class="note"><div class="note-title" aria-level="4" role="heading" id="h_note_6"><span>Note</span></div><p class="">The algorithm for selecting subtitle and caption tracks based on user preference and content metadata is
- not specified here.</p></div>
-
- <div class="note"><div class="note-title" aria-level="4" role="heading" id="h_note_7"><span>Note</span></div><p class="">Future versions of [<cite><a class="bibref" href="#bib-TTML1">TTML1</a></cite>] might introduce more generic mechanisms for conditional display of content elements.</p></div>
+ <div class="note"><div class="note-title" aria-level="4" role="heading" id="h_note_7"><span>Note</span></div><p class="">It is expected that the functionality of <code>itts:forcedDisplay</code> will be mapped to a conditional style construct in a future revision of this specification.</p></div>
</section>
<section id="ttm-altText" typeof="bibo:Chapter" resource="#ttm-altText" rel="bibo:Chapter">
@@ -2658,8 +2654,31 @@
</table>
</section>
+ <section class="appendix" id="forced-content" typeof="bibo:Chapter" resource="#forced-content" rel="bibo:Chapter">
+
+ <!--OddPage--><h2 aria-level="1" role="heading" id="h2_forced-content"><span class="secno">B. </span>Forced content</h2>
+
+ <p><a href="#fig-forced-content" class="fig-ref">Fig. <span class="figno">3</span> <span class="fig-title">
+ Illustration of the use of itts:forcedDisplay
+ </span></a> below illustrates the use of forced content, i.e. <code>itts:forcedDisplay</code> and <code>displayForcedOnlyMode</code>. The content with <code>itts:forcedDisplay</code>="true" is the French translation of the "High School" sign. The content with <code>itts:forcedDisplay</code>="false" are French subtitles capturing a voiceover.</p>
+
+ <figure id="fig-forced-content">
+ <img src="forced-example-figure-1.png" alt="Illustration of the use of itts:forcedDisplay">
+
+ <figcaption>Fig. <span class="figno">3</span> <span class="fig-title">
+ Illustration of the use of itts:forcedDisplay
+ </span></figcaption>
+ </figure>
+
+ <p>When the user selects French as the playback language but does not select French subtitles, <code>displayForcedOnlyMode</code> is set to "true", causing the display of the sign translation, which is useful to any French speaker, but hiding the voiceover subtitles as the voiceover is heard in French.</p>
+<p>If the user selects French as the playback language and also selects French subtitles, e.g. if the user is hard-of-hearing, <code>displayForcedOnlyMode</code> is set to "false", causing the display of both the sign translation and the voiceover subtitles.</p>
+
+<p>The algorithm for selecting the value <code>displayForcedOnlyMode</code> and the appropriate combination of subtitle and audio tracks is not specified here and left to the application.</p>
+ </section>
+
+
<section class="appendix" id="wcag-applications" typeof="bibo:Chapter" resource="#wcag-applications" rel="bibo:Chapter">
- <!--OddPage--><h2 aria-level="1" role="heading" id="h2_wcag-applications"><span class="secno">B. </span>WCAG Considerations</h2>
+ <!--OddPage--><h2 aria-level="1" role="heading" id="h2_wcag-applications"><span class="secno">C. </span>WCAG Considerations</h2>
<p>This Section <em class="rfc2119" title="SHALL">SHALL</em> apply to applications following the guidelines at [<cite><a class="bibref" href="#bib-WCAG20">WCAG20</a></cite>].</p>
@@ -2676,17 +2695,17 @@
</section>
<section class="appendix" id="features-and-extensions" typeof="bibo:Chapter" resource="#features-and-extensions" rel="bibo:Chapter">
- <!--OddPage--><h2 aria-level="1" role="heading" id="h2_features-and-extensions"><span class="secno">C. </span>Extensions</h2>
+ <!--OddPage--><h2 aria-level="1" role="heading" id="h2_features-and-extensions"><span class="secno">D. </span>Extensions</h2>
<section class="appendix" id="general-2">
- <h3 aria-level="2" role="heading" id="h3_general-2"><span class="secno">C.1 </span>General</h3>
+ <h3 aria-level="2" role="heading" id="h3_general-2"><span class="secno">D.1 </span>General</h3>
<p>The following sections define extension designations, expressed as relative URIs (fragment identifiers) relative to the
IMSC 1.0 Extension Namespace base URI.</p>
</section>
<section class="appendix" id="progressivelydecodable">
- <h3 aria-level="2" role="heading" id="h3_progressivelydecodable"><span class="secno">C.2 </span>#progressivelyDecodable</h3>
+ <h3 aria-level="2" role="heading" id="h3_progressivelydecodable"><span class="secno">D.2 </span>#progressivelyDecodable</h3>
<p>A TTML transformation processor supports the <code>#progressivelyDecodable</code> feature if it recognizes and is capable
of transforming values of the <a href="#ttp-progressivelyDecodable"><code>ittp:progressivelyDecodable</code></a>.</p>
@@ -2697,7 +2716,7 @@
</section>
<section class="appendix" id="aspectratio">
- <h3 aria-level="2" role="heading" id="h3_aspectratio"><span class="secno">C.3 </span>#aspectRatio</h3>
+ <h3 aria-level="2" role="heading" id="h3_aspectratio"><span class="secno">D.3 </span>#aspectRatio</h3>
<p>A TTML transformation processor supports the <code>#aspectRatio</code> feature if it recognizes and is capable of
transforming values of the <a href="#ttp-aspectRatio"><code>ittp:aspectRatio</code></a>.</p>
@@ -2707,7 +2726,7 @@
</section>
<section class="appendix" id="forceddisplay">
- <h3 aria-level="2" role="heading" id="h3_forceddisplay"><span class="secno">C.4 </span>#forcedDisplay</h3>
+ <h3 aria-level="2" role="heading" id="h3_forceddisplay"><span class="secno">D.4 </span>#forcedDisplay</h3>
<p>A TTML transformation processor supports the <code>#forcedDisplay</code> feature if it recognizes and is capable of
transforming values of the <a href="#tts-forcedDisplay"><code>itts:forcedDisplay</code></a>.</p>
@@ -2718,7 +2737,7 @@
</section>
<section class="appendix" id="alttext">
- <!--OddPage--><h2 aria-level="1" role="heading" id="h2_alttext"><span class="secno">D. </span>#altText</h2>
+ <!--OddPage--><h2 aria-level="1" role="heading" id="h2_alttext"><span class="secno">E. </span>#altText</h2>
<p>A TTML transformation processor supports the <code>#altText</code> feature if it recognizes and is capable of
transforming values of the <a href="#ttm-altText"><code>ittm:altText</code></a> element.</p>
@@ -2729,7 +2748,7 @@
-<section id="references" class="appendix" typeof="bibo:Chapter" resource="#references" rel="bibo:Chapter"><!--OddPage--><h2 aria-level="1" role="heading" id="h2_references"><span class="secno">E. </span>References</h2><section id="normative-references" typeof="bibo:Chapter" resource="#normative-references" rel="bibo:Chapter"><h3 aria-level="2" role="heading" id="h3_normative-references"><span class="secno">E.1 </span>Normative references</h3><dl class="bibliography" about=""><dt id="bib-CLDR">[CLDR]</dt><dd rel="dcterms:requires">Unicode Consortium. <a href="http://cldr.unicode.org">The Common Locale Data Repository Project</a>
+<section id="references" class="appendix" typeof="bibo:Chapter" resource="#references" rel="bibo:Chapter"><!--OddPage--><h2 aria-level="1" role="heading" id="h2_references"><span class="secno">F. </span>References</h2><section id="normative-references" typeof="bibo:Chapter" resource="#normative-references" rel="bibo:Chapter"><h3 aria-level="2" role="heading" id="h3_normative-references"><span class="secno">F.1 </span>Normative references</h3><dl class="bibliography" about=""><dt id="bib-CLDR">[CLDR]</dt><dd rel="dcterms:requires">Unicode Consortium. <a href="http://cldr.unicode.org">The Common Locale Data Repository Project</a>
</dd><dt id="bib-MHP">[MHP]</dt><dd rel="dcterms:requires">ETSI TS 101 812 V1.3.1, Digital Video Broadcasting (DVB); Multimedia Home
</dd><dt id="bib-RFC2119">[RFC2119]</dt><dd rel="dcterms:requires">S. Bradner. <a href="http://www.ietf.org/rfc/rfc2119.txt"><cite>Key words for use in RFCs to Indicate Requirement Levels</cite></a>. March 1997. Best Current Practice. URL: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a>
</dd><dt id="bib-ST2052-1">[ST2052-1]</dt><dd rel="dcterms:requires">SMPTE ST 2052-1, Timed Text Format (SMPTE-TT)
@@ -2737,7 +2756,7 @@
</dd><dt id="bib-UNICODE">[UNICODE]</dt><dd rel="dcterms:requires"><a href="http://www.unicode.org/versions/latest/"><cite>The Unicode Standard</cite></a>. URL: <a href="http://www.unicode.org/versions/latest/">http://www.unicode.org/versions/latest/</a>
</dd><dt id="bib-WCAG20">[WCAG20]</dt><dd rel="dcterms:requires">Ben Caldwell; Michael Cooper; Loretta Guarino Reid; Gregg Vanderheiden et al. <a href="http://www.w3.org/TR/WCAG20/"><cite>Web Content Accessibility Guidelines (WCAG) 2.0</cite></a>. 11 December 2008. W3C Recommendation. URL: <a href="http://www.w3.org/TR/WCAG20/">http://www.w3.org/TR/WCAG20/</a>
</dd><dt id="bib-xml-names">[xml-names]</dt><dd rel="dcterms:requires">Tim Bray; Dave Hollander; Andrew Layman; Richard Tobin; Henry Thompson et al. <a href="http://www.w3.org/TR/xml-names"><cite>Namespaces in XML 1.0 (Third Edition)</cite></a>. 8 December 2009. W3C Recommendation. URL: <a href="http://www.w3.org/TR/xml-names">http://www.w3.org/TR/xml-names</a>
-</dd></dl></section><section id="informative-references" typeof="bibo:Chapter" resource="#informative-references" rel="bibo:Chapter"><h3 aria-level="2" role="heading" id="h3_informative-references"><span class="secno">E.2 </span>Informative references</h3><dl class="bibliography" about=""><dt id="bib-CEA-608">[CEA-608]</dt><dd rel="dcterms:references"><a href="http://www.ce.org/Standards/Standard-Listings/R4-3-Television-Data-Systems-Subcommittee/Line-21-Data-Service.aspx">Line-21 Data Services</a>, ANSI/CEA Standard.
+</dd></dl></section><section id="informative-references" typeof="bibo:Chapter" resource="#informative-references" rel="bibo:Chapter"><h3 aria-level="2" role="heading" id="h3_informative-references"><span class="secno">F.2 </span>Informative references</h3><dl class="bibliography" about=""><dt id="bib-CEA-608">[CEA-608]</dt><dd rel="dcterms:references"><a href="http://www.ce.org/Standards/Standard-Listings/R4-3-Television-Data-Systems-Subcommittee/Line-21-Data-Service.aspx">Line-21 Data Services</a>, ANSI/CEA Standard.
</dd><dt id="bib-CEA-708">[CEA-708]</dt><dd rel="dcterms:references"><a href="http://www.ce.org/Standards/Standard-Listings/R4-3-Television-Data-Systems-Subcommittee/CEA-708-D.aspx">Digital Television (DTV) Closed Captioning</a>, ANSI/CEA Standard.
</dd><dt id="bib-HTML5">[HTML5]</dt><dd rel="dcterms:references">Robin Berjon; Steve Faulkner; Travis Leithead; Erika Doyle Navara; Edward O'Connor; Silvia Pfeiffer. <a href="http://www.w3.org/TR/html5/"><cite>HTML5</cite></a>. 17 June 2014. W3C Last Call Working Draft. URL: <a href="http://www.w3.org/TR/html5/">http://www.w3.org/TR/html5/</a>
</dd><dt id="bib-SDPUS">[SDPUS]</dt><dd rel="dcterms:references">World Wide Web Consortium (W3C). <a href="http://www.w3.org/TR/ttml10-sdp-us/">TTML Simple Delivery Profile for Closed Captions (US)</a> (W3C Working Group Note, 05 February 2013)
--- a/ttml-ww-profiles/ttml-ww-profiles.source.html Fri Jul 11 18:43:53 2014 -0700
+++ b/ttml-ww-profiles/ttml-ww-profiles.source.html Wed Jul 16 20:33:21 2014 -0700
@@ -381,16 +381,9 @@
<section id='tts-forcedDisplay'>
<h4>itts:forcedDisplay</h4>
- <p><code>itts:forcedDisplay</code> identifies <em>Forced</em> subtitle content. <em>Forced</em> subtitle content is
- subtitle content that represents audio (e.g. foreign language) or text (e.g. a sign) that is not translated in the
- audio/video presentation, e.g. Na'vi language in the movie Avatar. As such <em>Forced</em> subtitle content is useful
- whether the user has explicitly requested subtitles to be displayed.</p>
-
- <p>When presenting a subtitle document, a presentation processor SHOULD display content for which the computed value of
- <code>itts:forcedDisplay</code> is <code>true</code>, regardless of whether the user has explicitly requested display of
- subtitle content.</p>
-
- <table class="simple">
+ <p><code>itts:forcedDisplay</code> identifies forced content, which represents audio (e.g. foreign language) or text (e.g. a sign) that is not translated in the audio/video presentation. The presentation of elements based their computed <code>itts:forcedDisplay</code> value is controlled using the <code>displayForcedOnlyMode</code> application parameter. Annex <a href='#forced-content'></a> illustrates the use of <code>itts:forcedDisplay</code>.</p>
+
+ <table class="simple">
<colgroup>
<col style="width:25%" span="1">
<col span="1">
@@ -435,15 +428,18 @@
</tbody>
</table>
+ <p>The presentation processor SHALL accept an optional boolean parameter called <code>displayForcedOnlyMode</code>, whose value MAY be set by the application. If not set, the value of <code>displayForcedOnlyMode</code> SHALL be assumed to be equal to "false".</p>
+
+ <p>If the value of <code>displayForcedOnlyMode</code> is "true", a content element with a <code>itts:forcedDisplay</code> computed value of "false" shall be assumed to have a <code>tts:visibility</code> computed value equal to "hidden", even if <code>tts:visibility</code> is otherwise set to "true".</p>
+
+ <p class='note'>A region will remain visible even if all content elements have a computed <code>tts:visibility</code> value of "hidden" unless <code>tts:showBackground</code> is set to "whenActive" (the initial value of <code>tts:showBackground</code> is "always".)</p>
+
<p class='note'>Although <code>itts:forcedDisplay</code>, like all the TTML style attributes, has no defined semantics on a
<code>br</code> content element, <code>itts:forcedDisplay</code> will apply to a <code>br</code> content element if it is
either defined on an ancestor content element of the <code>br</code> content element or it is applied to a region element
corresponding to a region that the <code>br</code> content element is being flowed into.</p>
- <p class='note'>The algorithm for selecting subtitle and caption tracks based on user preference and content metadata is
- not specified here.</p>
-
- <p class='note'>Future versions of [[!TTML1]] might introduce more generic mechanisms for conditional display of content elements.</p>
+ <p class='note'>It is expected that the functionality of <code>itts:forcedDisplay</code> will be mapped to a conditional style construct in a future revision of this specification.</p>
</section>
<section id='ttm-altText'>
@@ -2367,6 +2363,27 @@
</table>
</section>
+ <section class='appendix' id='forced-content'>
+
+ <h2>Forced content</code></h2>
+
+ <p><a href='#fig-forced-content'></a> below illustrates the use of forced content, i.e. <code>itts:forcedDisplay</code> and <code>displayForcedOnlyMode</code>. The content with <code>itts:forcedDisplay</code>="true" is the French translation of the "High School" sign. The content with <code>itts:forcedDisplay</code>="false" are French subtitles capturing a voiceover.</p>
+
+ <figure id='fig-forced-content'>
+ <img src="forced-example-figure-1.png" alt="Illustration of the use of itts:forcedDisplay">
+
+ <figcaption>
+ Illustration of the use of itts:forcedDisplay
+ </figcaption>
+ </figure>
+
+ <p>When the user selects French as the playback language but does not select French subtitles, <code>displayForcedOnlyMode</code> is set to "true", causing the display of the sign translation, which is useful to any French speaker, but hiding the voiceover subtitles as the voiceover is heard in French.</p>
+<p>If the user selects French as the playback language and also selects French subtitles, e.g. if the user is hard-of-hearing, <code>displayForcedOnlyMode</code> is set to "false", causing the display of both the sign translation and the voiceover subtitles.</p>
+
+<p>The algorithm for selecting the value <code>displayForcedOnlyMode</code> and the appropriate combination of subtitle and audio tracks is not specified here and left to the application.</p>
+ </section>
+
+
<section class='appendix' id='wcag-applications'>
<h2>WCAG Considerations</h2>