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Re: [codec] SDP mapping for > 2 channels in OPUS?

Jean-Marc Valin <jmvalin@jmvalin.ca> Tue, 12 February 2019 22:41 UTC

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To: Harald Alvestrand <harald@alvestrand.no>, codec@ietf.org
References: <15e1a439-bdc1-cd5f-8c9b-ee02c0248a30@alvestrand.no>
From: Jean-Marc Valin <jmvalin@jmvalin.ca>
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Date: Tue, 12 Feb 2019 17:41:11 -0500
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Subject: Re: [codec] SDP mapping for > 2 channels in OPUS?
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Hi Harald,

There's no such spec yet. It probably would not be too hard to come up
with one, starting from the RFC7845 and RFC8486. That being said, I
think we would need to define a new payload and corresponding media
subtype to avoid compatibility problems with RFC7587.

Cheers,

	Jean-Marc


On 02/12/2019 03:50 PM, Harald Alvestrand wrote:
> Hi,
> 
> I wonder if there exists some specification for multichannel OPUS in SDP
> - I have searched for it and missed it.
> 
> I note that RFC 8486 (ambisonics) doesn't say anything about SDP
> considerations.
> 
> Harald
> 
> 
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