[MPlayer-dev-eng] MPlayer and raw video

[Mats Peterson]

"Reimar Döffinger" <Reimar.Doeffinger at gmx.de> skrev: (25 februari 2016 22:34:49 CET)
>On Thu, Feb 25, 2016 at 09:59:13PM +0100, Mats Peterson wrote:
>> On 02/25/2016 09:52 PM, compn wrote:
>> >On Thu, 25 Feb 2016 21:12:19 +0100
>> >Mats Peterson <matsp888-at-yahoo.com at ffmpeg.org> wrote:
>> >
>> >>I just downloaded r37799, and there are still problems with raw
>video
>> >>in Matroska. Not that it's overly much used, except by me, who
>likes
>> >>to store everything in Matroska nowadays. But it's on the right
>> >>track, at least. FFplay handles all of these files correctly (as
>> >>expected), so perhaps it would be a good idea to use libavformat's
>> >>demuxer for files containing raw video, if at all possible. As you
>> >>said yourself, it's hardly top priority, and I know that too, but I
>> >>just wanted to make you guys aware of the problems.
>> >
>> >mplayer uses lavf mkv by default since a few years, because we
>stopped
>> >maintaining mplayer mkv demuxer. mplayer mkv demuxer has problems
>with
>> >h264 iirc.
>> >
>> 
>> Interesting fact that it uses lavf mkv. Then it should work
>correctly, but
>> try this Matroska file with uncompressed 8 bpp QuickTime video, and
>which
>> MPlayer plays with the wrong colors (works fine with FFplay):
>> 
>> https://drive.google.com/open?id=0B3_pEBoLs0faVmFONjBZMlhYQWc
>
>Lavf doesn't put the palette where our raw decoder expects it
>in that case.
>I'll make the FFmpeg one the default for paletted formats,
>it probably will work better anyway at least in those cases.
>Though I'll have to add that I think this file is an abomination,
>it uses the quicktime wrapping format to store raw video, so
>it's basically a mov file in a MKV file!
>Either MKV does not support paletted raw natively, then
>it should be added, or it does and then the program
>that created this should be considered broken.
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It's not an abomination, it's a perfectly valid Matroska file containing a V_QUICKTIME track, and the private data contains the  video sample description (including the palette)  from the QuickTime 'stsd' atom, exactly in accordance with the Matroska codec specs. It's muxed with mkvmerge for the record. The palette will be stored in a side data packet on demuxing. See libavformat/matroskadec.c in FFmpeg for details.
-- 
Mats Peterson
http://matsp888.no-ip.org/~mats/