[MPlayer-users] Bug report: ffmpeg creates a better file than mencoder

[Igor Katson]

I want to extract a png image from lots a videofiles, provided a seek point. In 80% of 
the cases, -vo png does this successfully.
The cmd in this case is e.g

mplayer video.avi -frames 1 -ss 1 -vo png

But there are files with broken index or smth (here I can't figure out the reason), like the one attached, and -vo png does not 
produce any output. Options -idx and -forceidx do not help. The output in this case is e.g. the following (if -v turned on):

Starting playback...
ds_fill_buffer: EOF reached (stream: video)  
EOF code: 1    0 ??% ??% ??,?% 0 0

I solve this problem by reencoding the video with ffmpeg (it's quite 
little in size), but when I do this with mencoder, the video is reencoded, but 
there is still no out png file.
The cmd in this case  is e.g.
mencoder video.3gp -ovc lavc -nosound -o video.avi . The only error output with the sample file is:

ODML: Aspect information not (yet?) available or unspecified, not writing vprp header.

Tried also -idx, -forceidx, -of lavf, -ovc xvid and other. Nothing helps. If I choose -of 
lavf (and with svn 25-12-2008 it happens even without -of lavf), I get the following errors:

[mpeg4 @ 0xf8ce80]hmm, seems the headers are not complete, trying to 
guess time_increment_bits
[mpeg4 @ 0xf8ce80]my guess is 1 bits ;)
[mpeg4 @ 0xf8ce80]Error, header damaged or not MPEG4 header (qscale=0)
[mpeg4 @ 0xf8ce80]header damaged
Error while decoding frame!

But the file is still playable.

If I do this with ffmpeg (all the default options), like ffmpeg -i input.3gp -an output.avi, it works flawlessly, 
and mplayer extracts the png image nicely.

I want to be able to reencode the video with mencoder, not to build 
ffmpeg on the target servers.

Tried on 2 machines: ubuntu 2.6.27, and debian 2.6.18.
Tried on 2 versions: mplayer 1.0rc2 and mplayer svn checkout 25-12-2008, both self-compiled

Thanks in advance,
Igor Katson

P.S. Attached a sample file. Don't blame for the content, it is just one of the thousands of crappy files, uploaded by someone.

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