Re: [codec] it MUST NOT exceed 1275 bytes?

"Christian Hoene" <hoene@uni-tuebingen.de> Mon, 25 July 2011 18:46 UTC

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From: "Christian Hoene" <hoene@uni-tuebingen.de>
To: "'Gregory Maxwell'" <gmaxwell@juniper.net>, <codec@ietf.org>
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Date: Mon, 25 Jul 2011 14:46:12 -0400
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Subject: Re: [codec] it MUST NOT exceed 1275 bytes?
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Hi Gergory,

> The ability to pack multiple frames is also requirement for the ability to
> produce constant duration packets even if the underlying transform block
> size is changing due to changing signal characteristics.  As such this
> is deeply a codec layer issue, as it allows the codec to be able to meet
> a reasonable requirement (constant duration frames) while changing
> modes based on its coding analysis.

[Christian Hoene] Uuh, be careful, there is a Fraunhofer claim on switching
frame sizes depending on signal information. 
The algorithm that you describe is not part of the reference implementation,
isn't it?

> What cost do you perceive this feature to have, and what benefit would
> we enjoy by removing it?

[Christian Hoene] It is the cost of complexity. I am just following the
saying "Everything should be made as simple as possible, but not simpler."

Currently, the Opus draft has a couple of features that do not belong in the
Codec WG nor in the Opus spec. 

Christian