[FFmpeg-devel] [PATCH 1/3] lavf/riffenc: Improve spec compliance

[Mats Peterson]

Hendrik Leppkes <h.leppkes at gmail.com> skrev: (11 mars 2016 09:18:43 CET)
>On Fri, Mar 11, 2016 at 5:10 AM, Mats Peterson
><matsp888-at-yahoo.com at ffmpeg.org> wrote:
>>
>> Regarding the biClrUsed field, I'm setting it to 1 <<
>> bits_per_coded_sample if palettized video, since setting it to 0 is
>> another case where it won't work with Windows Media Player and
>Microsoft
>> Video 1 in 8 bpp mode.
>>
>
>This is not "spec compliance" then, because the spec specifically says
>that when its 0, it should be assumed equal to 2^biBitCount, which is
>the same value you are explicitly writing now.
>Its a redundant value to work around the inability of some players,
>not spec compliance - the existing value is perfectly compliant.
>Please clarify as much in any potential commit message.
>
>- Hendrik
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I know all that, Hendrik, but the fact is Windows Media Player will not interpret 0 as 256 either for Microsoft Video 1 (CRAM) or RLE4/8. And the way I interpret the specs is that using 0 is only relevant to raw, uncompressed video.

Mats
-- 
Mats Peterson
http://matsp888.no-ip.org/~mats/