Re: [rtcweb] No Plan - PT based MUX

Cullen Jennings <fluffy@iii.ca> Thu, 30 May 2013 17:07 UTC

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From: Cullen Jennings <fluffy@iii.ca>
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Date: Thu, 30 May 2013 11:07:17 -0600
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To: Emil Ivov <emcho@jitsi.org>
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Subject: Re: [rtcweb] No Plan - PT based MUX
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So my read of this draft is that it allows two camera to send on the same PT but the applications would demux them based on SSRC and the browser would only look at the PT. 

I can't understand how this would possibly work. Lets say they are both VP8, we two different VP8 decoder contexts. The jitter buffers for the two need to be different. Unless that VP8 decoder is in the JS along with the jitter buffer, how does this work ?


On May 29, 2013, at 12:59 PM, Emil Ivov <emcho@jitsi.org> wrote:

> Hey all,
> 
> Based on many of the discussions that we've had here, as well as many others that we've had offlist, it seemed like a good idea to investigate a negotiation alternative that relies on SDP and Offer/Answer just a little bit less.
> 
> The following "no plan" draft attempts to present one such approach:
> 
> http://tools.ietf.org/html/draft-ivov-rtcweb-noplan
> 
> The draft relies on conventional use of SDP O/A but leaves the intricacies of multi-source scenarios to application-specific signalling, with potentially a little help from RTP.
> 
> Hopefully, proponents of Plans A and B would find that the interoperability requirements that concerned them can still be met with "no plan". Of course they would have to be addressed by application-specific signalling and/or signalling gateways.
> 
> Comments are welcome!
> 
> Cheers,
> Emil
> 
> -- 
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