Re: [rtcweb] Basic scenario 'impossible?' to achieve with the actual API

Lorenzo Miniero <lorenzo@meetecho.com> Wed, 03 July 2013 12:32 UTC

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Date: Wed, 3 Jul 2013 14:31:58 +0200
From: Lorenzo Miniero <lorenzo@meetecho.com>
To: =?UTF-8?B?ScOxYWtp?= Baz Castillo <ibc@aliax.net>
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Subject: Re: [rtcweb] Basic scenario 'impossible?' to achieve with the actual API
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Il giorno Wed, 3 Jul 2013 13:58:54 +0200
Iñaki Baz Castillo <ibc@aliax.net> ha scritto:

> 2013/7/2 Lorenzo Miniero <lorenzo@meetecho.com>om>:
> > In the case of Alice trying to add video and Bob rejecting it,
> > there may be no callback as of now, but the JS application should
> > already have a way to know the video has been rejected
> > nevertheless. It might just look at the updated MediaStream
> > instance: if nothing changed, video was rejected (unless in case
> > Bob is only receiving video and not sending it, e.g., because it
> > has no webcam, there would be no video track as well?).
> 
> One more comment about this:
> 
> The fact that Alice offers video to Bob does not mean that Bob also
> should offer video to Alice. It could perfectly occur that Alice
> offers video to Bob, Bob accepts receiving it but Bob does not send
> video to Alice (i.e. "a=recvonly").
> 


Yes, that's what I meant by the "unless...": I'm not sure a remote
MediaStream would look different in case of no video at all or a
recvonly video. If not, I agree that not even the ugly approach I
mentioned would work.

L.


> The problem described in this issue is the fact that Alice has no way
> to realize whether Bob has accepted receiving her video or not. Bob
> has replied to the video offer with "m=video 0" or "a=inactive", which
> means that there won't be video RTP from Alice to Bob. But there is no
> way for Alice's JS to realize of that so Alice's will expect that Bob
> is receiving her video (when he is not). There is no API callback to
> know whether the remote has accepted our flows or not.
> 
> 
> --
> Iñaki Baz Castillo
> <ibc@aliax.net>