Re: [rtcweb] Agenda time request for draft-marjou-rtcweb-audio-codecs-for-interop-01

Xavier Marjou <> Wed, 13 March 2013 15:17 UTC

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Date: Wed, 13 Mar 2013 11:17:44 -0400
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From: Xavier Marjou <>
To: Ron <>
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Subject: Re: [rtcweb] Agenda time request for draft-marjou-rtcweb-audio-codecs-for-interop-01
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WebRTC standard must do the best to avoid transcoding when communications
happen towards "legacy" devices.

Another way to illustrate that is an analogy with human languages: suppose
there are two French native speakers and they have to speak English to talk
with each other: this results in additional efforts, decreased quality of
conversation, additional delays... all these details are significant for
the quality of the communication.

(of course there are some exceptions in my analogy: there exists French
native speakers who can also speak English fluently, in particular some
Quebecois folks on the list ;-)

Are you aware of the listening tests presented to the CODEC WG?
> In particular the ones that show Opus->AMR and AMR->Opus is not
> significantly
> worse than the intrinsic quality degradation suffered by using AMR alone?
> Or that Opus->G.711->AMR is actually better than AMR->G.711->AMR ?