Accessibility/IA2 1.3: Difference between revisions

Accessibility/IA2 1.3 (view source)

Revision as of 13:11, 8 June 2011

7 bytes removed , 8 June 2011

clean-up on the cue text handling for video

Silviapfeiffer

401

edits

@@ Line 252: / Line 252: @@
    HRESULT play();
    HRESULT pause();
-  HRESULT stop();
    HRESULT un/mute();
    HRESULT get/setVolume();
@@ Line 264: / Line 263: @@
       [out, retval] number);
-   IAccessibleTextTrack[] getTextTracks();
+   IAccessibleTrack[] getTextTracks();
-   IAccessibleMediaTrack[] getAudioTracks();
+   IAccessibleTrack[] getAudioTracks();
-   IAccessibleMediaTrack[] getVideoTracks();
+   IAccessibleTrack[] getVideoTracks();
 }
 </pre>
 <pre>
-interface IAccessibleTextTrack : public IUnknown
+interface IAccessibleTrack : public IUnknown
-{
-  HRESULT kind;
-  HRESULT label;
-  HRESULT language;
-  HRESULT enabled;
-  IAccessibleTextTrackCue[] getCues();
-}
-</pre>
-<pre>
-interface IAccessibleMediaTrack : public IUnknown
 {
    HRESULT kind;
@@ Line 295: / Line 283: @@
 Propose: provide a way to handle text descriptions and other text cues.
-[Note: here's a mix of my and Silvia suggestions, we get it clear after chat].
+) when the browser has a new cue available for a text track, then the browser fires a "MEDIA_TEXT_CUE_CHANGE" event at AT
+) AT picks up the cue, which causes the browser to set a "pauseOnExit" flag to true on this cue; from here on, the AT and the video play asynchronously
+.a) AT reads out cue and calls "GET_NEXT_CUE" when it is finished, which causes the browser to set the "pauseOnExit" flag to false and unpauses the video if it is paused
+.b) in parallel the browser plays video until the end of the cue; if the "pauseOnExit" flag is true when it reaches the end time of the cue, the video pauses, otherwise it continues playing
+repeat from 1)
-AT server fires event (MEDIA_TEXT_CUE_CHANGE) when text cue of a track changes while video/audio is played. AT client handles it and gets current cue text by
 <pre>
@@ Line 313: / Line 308: @@
    HRESULT startTime;
    HRESULT endTime;
-  HRESULT pauseOnExit;
 }
 </pre>
-If next event is fired before screen reader finished reading then AT server stops media until AT client gets the current text description, after that AT server makes sure media is playing.
 ===Text Descriptions and Subtitles for Video and Audio [Silvia description]===