HTML5 support for track metadata

Hi CG,

I think that the existing HTML5 CR spec [1] is very close to supporting the use cases that are being discussed in the CG. I propose submitting several HTML5 bugs to close the gap and I’m interested in your thoughts.

An alternative described in the CG wiki is to use kind and inBandMetadataTrackDispatchType attributes to expose track metadata: kind is used for all tracks except metadata text tracks and inBandMetadataTrackDispatchType is used for metadata text tracks. This covers the use cases that have been described in the CG but requires some additions to existing HTML5 CR sections:

1) Additions to the table "Return values for AudioTrack.kind() and VideoTrack.kind()” in [2] describing how @kind should be set for various track types. [3] shows the new additions for MPEG-2 TS and DASH media resources.

2) Text track equivalent of the table "Return values for AudioTrack.kind() and VideoTrack.kind()” in [2]. [4] shows such an equivalent table for setting @kind for text tracks in MPEG-2 TS and DASH. This could go in the HTML5 CR spec here [5].

3) Guidelines for creating in-band metadata text track cues. Here is the start for MPEG-2 TS [5]. This table could go here [6].

4) Additional definition for DASH describing how to set inBandMetadataTrackDispatchType[7].

Does anyone see a reason not to file bugs to add 1-4 above? These changes are consistent with the direction already taken in [1]. Making these changes wouldn’t preclude further work in the CG and would address use cases that have been identified so far.

Bob

[1] http://www.w3.org/TR/html5/
[2] http://www.w3.org/TR/html5/embedded-content-0.html#audiotracklist-and-videotracklist-objects
[3] https://www.w3.org/community/inbandtracks/wiki/Main_Page#Audio_and_video_kind_table
[4] https://www.w3.org/community/inbandtracks/wiki/Main_Page#Text_kind_table
[5] https://www.w3.org/community/inbandtracks/wiki/Main_Page#Guidelines_for_creating_metadata_text_track_cues
[6] http://www.w3.org/TR/html5/embedded-content-0.html#sourcing-in-band-text-tracks
[7] https://www.w3.org/community/inbandtracks/wiki/Main_Page#Exposing_a_Media_Resource_Specific_TextTrack