[MPlayer-users] QuickTime demuxer problem [bug?]

[Christoph Nägeli]

Hello,

Sorry, I sent the message to early...

I'm not quite sure if I found a bug in the QuickTime demuxer of 
mencoder.
I cut off of some parts of a movie encoded with libavcodecs mpeg4 codec 
and saved it as self contained QuickTime movie.
After that I wanted to compress it a little more using the xvid codec 
included in mencoder. But now the video track does no more start with a 
key frame. mencoder prints some error messages and the image gets 
heavily damaged.

I think the problem might be that each QuickTime track contains a media 
describing the video.  the media begins with a keyframe (though i'm not 
quite sure about that) but the track maps the media in its own 
time-coordinatespace, not necessarily beginning with the first frame of 
the media it contains, so the track does not begin with a key frame.
Is this scenario possible?

The sample movie is about 350 MB, but perhaps I can make a little 
samplemovie with the same problem if this could help.
Another Problem is I cannot make the movie public since I got no access 
to a public server.

Is there anything else you have to know?

Regards
Christoph