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Re: Explicit track cloning

From: Adam Bergkvist <adam.bergkvist@ericsson.com>
Date: Wed, 10 Apr 2013 07:41:54 +0200
Message-ID: <5164FBA2.2070208@ericsson.com>
To: Jim Barnett <Jim.Barnett@genesyslab.com>
CC: "public-media-capture@w3.org" <public-media-capture@w3.org>
On 2013-04-09 17:20, Jim Barnett wrote:
> I vote for *1*.  We just have to make it clear to developers what it
> means to put the same track in multiple MediaStreams.  As I
> understand it, a Track represents a set of settings/operations
> applied to the output of a device.  (These settings may or may not
> affect the state of the device.)  If a Track is in multiple
> MediaStreams, then any modification applied in one Stream is
> reflected immediately in the other.  I can't think of a use case for
> this off the top of my head[1], but I don't see any reason to
> disallow it.
>
> - Jim
> 1.  Suppose I am talking to someone over a PeerConnection and want my
> screen to reflect exactly what I am sending to the other side.  Would
> this be a case where I would have two MediaStreams, one added to a
> PeerConnection and the other connected to a <video> element?  If so,
> this is a case where I would want any change applied to a Track to
> show up in both MediaStreams simultaneously.  (I would want the audio
> muted in my local copy, but would want the video to be exactly the
> same.  So I would clone the audio track, or omit it altogether, and
> use the same video Track.)

Yes, that would be one way of solving it.

var selfViewStream = new MediaStream(sendStream.getVideoTracks());

/Adam
Received on Wednesday, 10 April 2013 05:42:20 UTC

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