Bug#601252: mplayer: video distortion with fftheora decoder

[Reimar Döffinger]

On Sun, Oct 24, 2010 at 01:29:08PM -0400, Nathan A. Stine wrote:
> On Sun, 2010-10-24 at 19:12 +0200, Reimar Döffinger wrote:
> > On Sun, Oct 24, 2010 at 12:55:39PM -0400, Nathan A. Stine wrote:
> > > Package: mplayer
> > > Version: 2:1.0~rc4~try1.dsfg1-1
> > > Severity: normal
> > > 
> > > When watching a theora-encoded file and using fftheora to decode, mplayer seems
> > > to introduce some distortion at the top of the video file.  This problem does
> > > not exist with the 3rd-party "standard" theora decoder.  I checked the file in
> > > ffplay and did not find the same distortion, so I believe this is an mplayer
> > > bug.
> > > 
> > > The file in question is here:
> > > 
> > > http://ia331209.us.archive.org/0/items/Patent_Absurdity/Patent_Absurdity_HD_3540kbit.ogv
> > > 
> > > A screenshot is attached to show the distortion.  The video is encoded at an
> > > interesting resolution: 1280x1088, which may contribute to the problem.
> > 
> > 
> > One or more of these FFmpeg revisions have not been backported to 0.6 I guess:
> > r23537, (r25050 not directly related), r25051, r25052, r25073
> 
> If this was an FFmpeg problem, ffplay should give the same distortion as
> mplayer, right?  I was under the impression that if I can reproduce a
> bug in mplayer and ffplay, I should submit it as an FFmpeg bug rather
> than mplayer.  Is this not the case?

You did nothing "wrong" in reporting this as an MPlayer bug,
however FFmpeg/ffplay does not use the slice rendering API
(except possibly if you use the right libavfilter filters)
so bugs that are exclusive to that will not be reproducible
with ffplay even if (like in this case) it actually is an
FFmpeg bug.