Re: [codec] Discussion around ITU LS

Anisse Taleb <Anisse.Taleb@huawei.com> Thu, 08 September 2011 10:44 UTC

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Date: Thu, 08 Sep 2011 10:38:16 +0000
From: Anisse Taleb <Anisse.Taleb@huawei.com>
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Cc: Jonathan Rosenberg <jonathan.rosenberg@skype.net>, "codec@ietf.org" <codec@ietf.org>
Subject: Re: [codec] Discussion around ITU LS
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Dear Jean Marc,

>> Does the WG consider  time shortening / stretching functionality they
>> would want to include in opus as a technique to use for PLC?

>While time stretching/shortening is something that can be useful, I
>don't think it's really necessary for a codec *specification*. In fact
>even the PLC is provided only as an example.


Quoting the requirements document RFC 6366:
"  It is desirable for the reference implementation to provide a time stretching/shortening
   implementation, although it should not be normative."

While I agree that this is something that should be non-normative, such an integrated implementation 
would be an important feature for any codec deployed on the internet and really differentiate Opus wrt. "codecs" which are considered unsuitable for the internet. 

Kind regards,
/Anisse