MEncoder problem with xvid ac3 convert

[MRAR]

hi
here is my code:

mencoder input.mp4 -oac lavc -lavcopts acodec=ac3:abitrate=384 -channels 6 -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=2000 -ffourcc XVID -o output.avi

when i play it in the windows 7 with "KMplayer" the video plays faster than audio. "jetaudio and vlc" plays video correctly but no sound and "media player classic" not playing that at all.

but when i copy the output into flash drive and connect it to the dvd player everything is fine (video and audio are sync perfect)

what is the problem? i use latest version of mencoder and i have k-lite codec pack installed on my pc
any reply could be helpful Thx

[LigH.de]

My guess would be that mencoder does not create a complete AVI container. Many containers need an update in their headers after the whole content has been written, but mencoder / ffmpeg usually write the file only once, so they may not be able to update header data already written before the conversion started. In addition, Alexander Noe (author of AviMux-GUI) lists a few reasons why AC3 audio streams may be an issue in AVI, but don't have to be if it is correctly implemented; who knows if mencoder does... In brief: Try to remultiplex your AVI, e.g. with AviMux-GUI or VirtualDubMod, and check if the copy still has issues.

By the way, *mplayer and VLC won't use any installed DirectShow filter, so it doesn't matter which Codec Pack you installed, it is never used by such players which use their own built-in decoders.

And another hint: If your mencoder build contains libxvid, I would prefer it over a generic libav MPEG-4 ASP encoder which only "masks" as Xvid via FourCC; the real Xvid encoder certainly has better optimized features.

[MRAR]

you were right avimux-gui fixed the avi file
is there any way to write/change header by myself (binary ,stream)?

And another hint: If your mencoder build contains libxvid, I would prefer it over a generic libav MPEG-4 ASP encoder which only "masks" as Xvid via FourCC; the real Xvid encoder certainly has better optimized features.

could you provide sum code for that?

thanks

[LigH.de]

It is documented for ffmpeg:

ffmpeg.org + doom9.org

Unfortunately, I have no example for mencoder. It may be similar. The Hybrid video converter by Selur or Tencoder may help you as GUIs.

[MRAR]

Anyone has a better idea??