Re: [rtcweb] confirming sense of the room: mti codec

Andrew Allen <> Mon, 08 December 2014 23:57 UTC

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From: Andrew Allen <>
To: Peter Saint-Andre - &yet <>, "" <>
Thread-Topic: [rtcweb] confirming sense of the room: mti codec
Date: Mon, 08 Dec 2014 23:57:49 +0000
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Subject: Re: [rtcweb] confirming sense of the room: mti codec
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We didn't define two audio MTI codecs for interoperability between RTCweb compatible devices. 

We defined OPUS as MTI for interoperability between RTCweb compatible devices and G.711 for interoperability with just about everything else out there (i.e with Legacy). Much to the consternation of some of my colleagues in the mobile industry I have been proactive in the audio codec discussion on resisting IETF defining any additional audio MTI codecs to these two.

Selecting H.264 as the single MTI for video would have fulfilled both the RTCweb interoperability and the legacy interoperability .

It also should be noted that G.711 is trivial to implement and does not have IPR concerns (G.711 is in that respect the equivalent of H.261 in the audio codec world).


-----Original Message-----
From: rtcweb [] On Behalf Of Peter Saint-Andre - &yet
Sent: Monday, December 08, 2014 1:51 PM
Subject: Re: [rtcweb] confirming sense of the room: mti codec

On 12/8/14, 11:34 AM, Andrew Allen wrote:
> I think it's pretty clear from my statements in the IETF session on 
> this topic and on this list that I don't support having two MTI  video 
> codecs for any WebRTC entity and I don't think it is technically 
> justified. But I state this here formally.

To those (not just Andrew) who are opposed to two MTI video codecs: were you also opposed to two MTI audio codecs? I'm trying to understand the differences between audio and video here...


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