- From: Cyril Concolato <cyril.concolato@telecom-paristech.fr>
- Date: Wed, 13 Nov 2013 03:03:55 +0100
- To: Brendan Long <B.Long@cablelabs.com>, "public-inbandtracks@w3.org" <public-inbandtracks@w3.org>
Hi Brendan, Le 12/11/2013 16:41, Brendan Long a écrit : >> Regarding clashes, does the Track.id attribute have to be unique in the >> page? or in the list of Tracks to which the Track belongs (AudioTracks, >> VideoTracks or TextTracks)? It doesn't make much sense to have a >> page-wide id, does it? > Interestingly, the spec currently doesn't require the track "id" to be unique: > >> The AudioTrack.id and VideoTrack.id attributes must return the identifier >> of the track, if it has one, or the empty string otherwise. If the media >> resource is in a format that supports the Media Fragments URI fragment >> identifier syntax, the identifier returned for a particular track must be the >> same identifier that would enable the track if used as the name of a track >> in the track dimension of such a fragment identifier. > http://www.w3.org/TR/html5/embedded-content-0.html#dom-audiotrack-id > >> Anyway, I had thought for the 'id' value to use a fragment identifier >> like 'file.mp4#track_id=1' or 'file.ts#pid=120'. That would avoid clashes. > I think right now the format is just "file.mp4#track=1" or "file.ts#track=120": > > http://www.w3.org/TR/2011/CR-media-frags-20111201/#naming-track Thanks for digging that information. I agree with the small caveat that using a fragment identifier as defined by the Media Fragment Identifier spec, only applies if the MIME type supports that. In particular, I need to check for MP4 and MPEG-2 TS. Cyril -- Cyril Concolato Maître de Conférences/Associate Professor Groupe Multimedia/Multimedia Group Telecom ParisTech 46 rue Barrault 75 013 Paris, France http://concolato.wp.mines-telecom.fr/
Received on Wednesday, 13 November 2013 02:04:26 UTC