Re: [codec] [Technical Errata Reported] RFC6716 (4853)

"Timothy B. Terriberry" <tterriberry@mozilla.com> Wed, 02 November 2016 20:11 UTC

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Date: Wed, 02 Nov 2016 13:11:11 -0700
From: "Timothy B. Terriberry" <tterriberry@mozilla.com>
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Subject: Re: [codec] [Technical Errata Reported] RFC6716 (4853)
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RFC Errata System wrote:
> --------------------------------------
> Type: Technical
> Reported by: Rostislav Pehlivanov <atomnuker@gmail.com>
>
> Section: 5.1.1
>
> Original Text
> -------------
>                                      rng
>                          rng = rng - --- * (fh - fl)
>                                      ft
>
> Corrected Text
> --------------
>                                      rng
>                          rng = rng - --- * (ft - fh)
>                                      ft
>
> Notes
> -----
> Equation should match with the one in the range decoder (section 4.1.2), however comparing the two and the reference implementation reveals the equation in section 5.1.1 to be incorrect.

I think this report is correct and should be Verified. Although the code 
is authoritative, this section of the text is complete enough for 
someone to implement this feature directly from the text, so it will 
cause confusion if they don't actually match.