Re: [MMUSIC] Channel descriptions

Harald Alvestrand <harald@alvestrand.no> Fri, 20 July 2012 12:13 UTC

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Subject: Re: [MMUSIC] Channel descriptions
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Kevin,

can you clarify what you mean by "channel" here?

The term is used most often for components of a multisource audio 
signal, such as stereo, 5+1 or 22+2 - in most cases, those will be 
carried in a single SSRC, using an encoding that implicitly defines 
which channels go where.

In WebRTC, we've converged on the word "track" for a single media flow 
such as one audio signal (mostly) carried in a single SSRC, and the word 
"stream" for multiple media flows (such as audio and video) that are 
related to each other in some fashion.

If you have a definition you would like to use, please point to it - the 
discussion can get to be almighty confusing if we're not talking about 
the same thing!

On 07/18/2012 01:57 AM, Kevin Gross wrote:
> The i= attribute provides a means to describe a session. Sessions 
> often have multiple media streams or channels. Although RFC 3551 (page 
> 8) suggests a convention for ordering of channels for surround sound 
> applications, other applications use multiple channels in different 
> ways. It would be useful if there were a mechanism analogous to i= for 
> describing individual channels in a session. Does such a thing exist 
> anywhere? I've searched the archives here and didn't find anything.
>
> Kevin Gross
> +1-303-447-0517
> Media Network Consultant
> AVA Networks - www.AVAnw.com <http://www.avanw.com/>, www.X192.org 
> <http://www.X192.org>
>
>
>
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