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Re: Changing track sources...

From: Timothy B. Terriberry <tterriberry@mozilla.com>
Date: Fri, 07 Dec 2012 10:07:22 -0800
Message-ID: <50C2305A.2020904@mozilla.com>
To: "public-media-capture@w3.org" <public-media-capture@w3.org>
Travis Leithead wrote:
> In the call, it was mentioned that we have a requirement to be able to change the source of a track while preserving the identity of the track for the purposes of a PeerConnection and possibly other reasons.

As I mentioned at TPAC, the ProcessedMediaStream from our previous 
MediaStream Processing API proposal 
(https://dvcs.w3.org/hg/audio/raw-file/tip/streams/StreamProcessing.html) had 
a pretty good model for all of this. Instead of allowing you to replace 
the source of an arbitrary track, it lets you compose a new stream from 
the contents of other streams, which can change over time, and produces 
a single output.

> Once you allow a track to be able to change its source, what do we do about a track's "ended" state?

The above proposal contains an "autofinish" attribute, defined thus:

"When the autofinish attribute is true, then when all stream inputs are 
finished (including if there are no inputs), the stream will 
automatically enter the finished state and never produce any more output 
(even if new inputs are attached)."
Received on Friday, 7 December 2012 18:07:52 UTC

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