Re: [rtcweb] Some thoughts on optional audio codecs

Enrico Marocco <> Wed, 17 July 2013 07:44 UTC

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Date: Wed, 17 Jul 2013 09:44:43 +0200
From: Enrico Marocco <>
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Subject: Re: [rtcweb] Some thoughts on optional audio codecs
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On 7/16/13 10:07 PM, Adam Roach wrote:
>>> In that draft, I would prefer something more in line with:
>>> "If other suitable audio codecs are available to the browser to use,
>>> it is recommended that they are also included in the offer in order
>>> to maximize the possibility to establish the session without the need
>>> for audio transcoding".
>> Yes, in fact this is happening already:
> You have misread that article. What that article says is that Mozilla is 
> adding select platform-supplied codecs to Firefox for non-WebRTC uses.

Sure, didn't mean to imply that it is happening for WebRTC.

> Our implementation of audio codecs for WebRTC continues to support PCMU, 
> PCMA, Opus, and nothing else; our implementation use VP8 exclusively for 
> video.

And that's pretty visible also from the outside. What's not visible is
whether at some point in time Mozilla will consider taking advantage of
OS/platform-provided encoding/decoding capabilities also for WebRTC. One
may be led to assume yes, as you're doing it for static content already.

But maybe different conditions apply here, and I don't expect them to be
discussed on this mailing list (even if it would be very, very