Re: [MMUSIC] Proposal for what bundle should say about demux

Paul Kyzivat <pkyzivat@alum.mit.edu> Fri, 24 May 2013 14:23 UTC

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Date: Fri, 24 May 2013 10:23:34 -0400
From: Paul Kyzivat <pkyzivat@alum.mit.edu>
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To: Martin Thomson <martin.thomson@gmail.com>
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Subject: Re: [MMUSIC] Proposal for what bundle should say about demux
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On 5/23/13 8:17 PM, Martin Thomson wrote:
> On 23 May 2013 14:34, Paul Kyzivat <pkyzivat@alum.mit.edu> wrote:
>> Or, you can view it as layered. Where the ssrc maps to an early stage of the
>> pipeline (selected by ssrc) that does the codec processing, and then a
>> different stage of the pipeline (selected by capture id from the header
>> extension) that switches the decoded output to a particular rendering
>> device.
>
> That is what I would do for that case.  At the layer I'm concerned
> about, this is still the same stream.  The fact that someone
> downstream might use other information to wiggle that around doesn't
> concern me greatly.

But it has an impact on what is signaled.

If I intend to use capture-id to associate with an m-line then I don't 
need to signal the SSRCs. The SSRCs may still be used to demux to a 
decoder, but for that they don't need to be known in advance.

This is important for plan A.

	Thanks,
	Paul