Re: [codec] Ogg Opus zero-length frames

Jean-Marc Valin <jmvalin@jmvalin.ca> Sat, 24 August 2013 04:11 UTC

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Date: Sat, 24 Aug 2013 00:11:23 -0400
From: Jean-Marc Valin <jmvalin@jmvalin.ca>
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To: "Timothy B. Terriberry" <tterribe@xiph.org>
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Cc: codec@ietf.org
Subject: Re: [codec] Ogg Opus zero-length frames
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I'm fine with the proposed text in general. I only have two comments below:

On 08/21/2013 09:00 PM, Timothy B. Terriberry wrote:
>    When possible, creating the TOC byte using the same
>    mode, audio bandwidth, channel count, and frame size as the previous
>    packet (if any) covers all losses that do not include a configuration
>    switch, as defined in Section 4.5 of [RFC6716].

Any way you can make that sentence easier to parse?

>    If
>    there is no previous packet, reasonable decoders will not emit
>    anything other than silence regardless of the mode.  Using the CELT-
>    only mode for this case (with any audio bandwidth) allows maximum
>    flexibility, since a single packet can represent any duration up to
>    120 ms that is a multiple of 2.5 ms using at most two bytes.

I think both these sentences should go since they add more confusion
than they help.

	Jean-Marc