ttml-ww-profiles/ttml-ww-profiles.source.html
changeset 636 2720fa1fae9c
parent 635 f350faa84e16
child 637 e78629db1b60
     1.1 --- a/ttml-ww-profiles/ttml-ww-profiles.source.html	Thu Jun 05 18:02:30 2014 +0900
     1.2 +++ b/ttml-ww-profiles/ttml-ww-profiles.source.html	Fri Jun 06 16:23:09 2014 -0700
     1.3 @@ -26,7 +26,8 @@
     1.4                    "MHP" : "ETSI TS 101 812 V1.3.1, Digital Video Broadcasting (DVB); Multimedia Home",
     1.5                    "ST2052-1": "SMPTE ST 2052-1, Timed Text Format (SMPTE-TT)",
     1.6                                    "SDPUS": "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)",
     1.7 -                                  "CLDR": "Unicode Consortium. <a href='http://cldr.unicode.org'>The Common Locale Data Repository Project</a>"
     1.8 +                                  "CLDR": "Unicode Consortium. <a href='http://cldr.unicode.org'>The Common Locale Data Repository Project</a>",
     1.9 +                                                                                                                                        
    1.10                }
    1.11          };
    1.12    </script>
    1.13 @@ -85,6 +86,10 @@
    1.14        <h3>General</h3>
    1.15  
    1.16        <p>A subtitle document SHALL NOT conform to the Text and Image Profiles simultaneously.</p>
    1.17 +
    1.18 +      <p class='NOTE'>Some applications require the same subtitle/caption content to be available in both text and image form
    1.19 +      simultaneously (see [[WCAG20]] for instance). For these applications, two distinct subtitle documents, one conforming to the
    1.20 +      Text Profile and the other conforming to the Image Profile, can be offered.</p>
    1.21      </section>
    1.22  
    1.23      <section>
    1.24 @@ -304,7 +309,9 @@
    1.25          <h4>ittp:progressivelyDecodable</h4>
    1.26  
    1.27          <p>A progressively decodable subtitle document is a subtitle document structured to facilitate processing before the
    1.28 -        document is received in its entirety. It shall conform to the following:</p>
    1.29 +        document is received in its entirety.</p>
    1.30 +
    1.31 +        <p>A progressively decodable subtitle document shall conform to the following:</p>
    1.32  
    1.33          <ol>
    1.34            <li>elements appear in the document in increasing order according to their resolved begin time;</li>
    1.35 @@ -349,9 +356,17 @@
    1.36        <section id='tts-forcedDisplay'>
    1.37          <h4>itts:forcedDisplay</h4>
    1.38  
    1.39 -        <p><code>itts:forcedDisplay</code> signals that a block of subtitle content is identified as <em>Forced</em> subtitle content.
    1.40 -        <em>Forced</em> subtitle content is subtitle content that represents audio (e.g. foreign language) or text (e.g. a sign)
    1.41 -        that is not translated in the audio/video presentation.</p>
    1.42 +        <p><code>itts:forcedDisplay</code> identifies <em>Forced</em> subtitle content. <em>Forced</em> subtitle content is
    1.43 +        subtitle content that represents audio (e.g. foreign language) or text (e.g. a sign) that is not translated in the
    1.44 +        audio/video presentation, e.g. Na&#39;vi language in the movie Avatar. As such <em>Forced</em> subtitle content is useful
    1.45 +        whether the user has explicitly requested subtitles to be displayed.</p>
    1.46 +
    1.47 +        <p>When presenting a subtitle document, a presentation processor SHOULD display content for which the computed value of
    1.48 +        <code>itts:forcedDisplay</code> is <code>true</code>, regardless of whether the user has explicitly requested display of
    1.49 +        subtitle content.</p>
    1.50 +
    1.51 +        <p class='note'>The algorithm for selecting subtitle and caption tracks based on user preference and content metadata is
    1.52 +        not specified here.</p>
    1.53  
    1.54          <table class="simple">
    1.55            <colgroup>
    1.56 @@ -399,9 +414,9 @@
    1.57          </table>
    1.58  
    1.59          <p class='note'>Although <code>itts:forcedDisplay</code>, like all the TTML style attributes, has no defined semantics on a
    1.60 -        <code>br</code> content element, <code>itts:forcedDisplay</code> will apply to a <code>br</code> content element if it is either defined
    1.61 -        on an ancestor content element of the <code>br</code> content element or it is applied to a region element corresponding to
    1.62 -        a region that the <code>br</code> content element is being flowed into.</p>
    1.63 +        <code>br</code> content element, <code>itts:forcedDisplay</code> will apply to a <code>br</code> content element if it is
    1.64 +        either defined on an ancestor content element of the <code>br</code> content element or it is applied to a region element
    1.65 +        corresponding to a region that the <code>br</code> content element is being flowed into.</p>
    1.66        </section>
    1.67      </section>
    1.68