xvid - missing b-frames

[gurke2]

hi,

i'm converting my dvds to mkv-container-files. the video data is encoded with xvid. in some movies, it seems that some b-frames are missing or incorrect. i have uploaded some screenshots of this problem: http://www.g4t3.de/xvid/xvid_problem.pdf
look at pictures 6 to 9...

besides, only some players have problems with the video-data. vlc (that i like to use) shows failures, mpc for example doesn't.

further more, the failure occures randomly. when i rip the same movie again, the failures occur in other cuts.

i'm using gordian knot to configure and create the matroska files... and i think that the problem could be solved with the quantisizer-settings... but i don't know for sure.

thanks for any help!

[foxyshadis]

The fact that the errors shift around in what should be a completely deterministic encode process (if you used the exact same settings) doesn't bode well. You should perform a complete system stability test, especially cpu and memory.

If it is a bug, it looks more like a decoder bug than an encoder one. (And it looks like it's an I-frame being skipped, not a b-frame.) Have you been able to replicate it on anything other than VLC, or anything that doesn't use the ffmpeg library? MPC doesn't have an mpeg-4 decoder, which one was it using?

I'd probably just find a nightly of VLC to test against, if it's still broken file a bug report. It's very important that you supply a sample stream, such as that scene extracted with vdub or avidemux. A pdf isn't very helpful.