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

Gaelle Martin-Cocher <> Fri, 12 December 2014 15:28 UTC

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From: Gaelle Martin-Cocher <>
To: "Mo Zanaty (mzanaty)" <>, "" <>
Thread-Topic: [rtcweb] confirming sense of the room: mti codec
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Date: Fri, 12 Dec 2014 15:27:57 +0000
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Subject: Re: [rtcweb] confirming sense of the room: mti codec
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Multiple codecs can be supported even if there is only a single MTI defined in WebRTC. 
This has been confirmed by those who will implement scalable codecs.

I am not aware of anyone asking for removing the codec negotiation/capability discovery even if there is a single MTI. 
As such supporting multiple codecs is independent from the MTI discussion.
The question is not do we need multiple codecs but do we need multiple MTIs (and which). 


-----Original Message-----
From: rtcweb [] On Behalf Of Mo Zanaty (mzanaty)
Sent: Monday, December 08, 2014 3:42 PM
To: Sean Turner;
Subject: Re: [rtcweb] confirming sense of the room: mti codec

To reiterate another point from the meeting, there are technical advantages to supporting multiple codecs. Dynamic discovery of local capabilities, negotiation of remote capabilities, understanding how different error resilience mechanisms can work (or not) with different codecs, faster adoption of new (non-mandatory) codecs, easier path to deprecating old (mandatory) codecs, etc. All those legs never get exercised effectively in single-codec implementations, leaving land mines in browsers, apps, services and sometimes even specs. They become easier or free once the groundwork is laid for multiple codecs. While some have argued against that extra complexity, I see it as essential for any important standard.