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

Iñaki Baz Castillo <ibc@aliax.net> Wed, 03 July 2013 11:59 UTC

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From: Iñaki Baz Castillo <ibc@aliax.net>
Date: Wed, 03 Jul 2013 13:58:54 +0200
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To: Lorenzo Miniero <lorenzo@meetecho.com>
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Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] Basic scenario 'impossible?' to achieve with the actual API
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2013/7/2 Lorenzo Miniero <lorenzo@meetecho.com>:
> 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").

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>