[Bug 26921] [InbandTracks] DASH trackId

https://www.w3.org/Bugs/Public/show_bug.cgi?id=26921

--- Comment #5 from Bob Lund <b.lund@cablelabs.com> ---
(In reply to Cyril Concolato from comment #4)
> > In the case of MSE, there is no need for representations as tracks. The Web
> > app already has access to all representations and can switch or not among
> > representations in an AS.
> > 
> > There is no defined HTML API for the Web app to determine when ABR switching
> > is off if the UA implements MPD processing and representation switching.
> > Further, representation switching by enabling/disabling video tracks is not
> > going to result in seamless switching.
> This clarifies your model. Thank you. I think it would be worth having an
> introduction in the DASH section describing that model.
> I've created a PR for that:
> https://github.com/w3c/HTMLSourcingInbandTracks/pull/30

This is a good introduction. The wording suggest that track objects are created
differently in the two cases, however. The following  is a slight modification.

 [[MPEGDASH]] defines formats for a media manifest, called MPD (Media
Presentation Description), which references media containers, called media
segments based on [[MPEG2TS]] or [[ISOBMFF]]. The user agent or the Web
application (using MSE [[MSE]]) may process the media manifests and fetch media
segments. When the user agent processes the MPD and fetches media segments, it
creates HTML track objects based on media segment and MPD data. When the Web
application processes the MPD and fetches media segments, the user agent also
creates HTML track objects using data in media segments  passed to it by the
Web application. The Web application may set default track attributes from MPD
data, using the trackDefaults object, that will be used by the user agent to
set attributes not set from initialization segment data.

Please update the PR if this is agreeable.

-- 
You are receiving this mail because:
You are the QA Contact for the bug.

Received on Monday, 20 October 2014 15:26:15 UTC