Re: [Gen-art] Review: draft-ietf-codec-oggopus-10

Ralph Giles <giles@thaumas.net> Fri, 15 January 2016 23:41 UTC

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From: Ralph Giles <giles@thaumas.net>
To: "Joel M. Halpern" <jmh@joelhalpern.com>
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Date: Fri, 15 Jan 2016 15:41:31 -0800
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Cc: General Area Review Team <gen-art@ietf.org>, draft-ietf-codec-oggopus.all@ietf.org, IETF discussion list <ietf@ietf.org>
Subject: Re: [Gen-art] Review: draft-ietf-codec-oggopus-10
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On 15/01/16 02:26 PM, Joel M. Halpern wrote:
> Minor issues:
>     While I do not completely understand ogg lacing values, there
> appears to be an internal inconsistency in the text in section 3:
> 1) "if the previous page with packet data does not end in a continued
> packet (i.e., did not end with a lacing value of 255)"
> 2) "a packet that continues onto a subsequent page (i.e., when the page
> ends with a lacing value of 255)"
>     The first quote says that continued packets end with a lacing value
> of 255, and the second quote says that continued packets end with a
> lacing value of less than 255.  At the very least, these need to be
> clarified.

Thanks for taking time to review the draft. You're right that the logic is inverted in the last section. I've corrected the i.e. clause in the last paragraph.
>     is there some way to indicate that the ogg encoding constraints
> (e.g. 48kHz granule and 2.5 ms timing) are sufficiently broad to cover
> all needed cases?

Hmm. RFC 6716 sec 2.1.3 and 2.1.4 give 48 kHz and 2.5 ms as the maximum sample rate and minumum packet duration, respectively. I suppose sec. 4 of the draft assumes these constraints.

It does indicate that 2.5 ms is the minimum packet duration, but we could add a reference, or a statement that 48 kHz is the effective maximum sample rate of the codec if it's cause for concern.

 -r