avidemux, missing audio stream, external audio file and out of sync A-V

lam_das · 28th November 2008, 23:28

Hi,

I have been bumping my head against this for a while and couldn't get anywhere. I hope someone has a solution for me.

I created a VOB file with mplayer -dumpstream. The VOB file plays fine with mplayer but audio stream is not found in the beginning. Sometime around 50 seconds (when the production logo and titles start) into the clip, the AC3 audio comes along and plays in sync with the video. No audio video sync problems with the movie's play.

Now, avidemux doesn't find any audio stream in the VOB mpeg header and just creates a video file. It doesn't show any audio in the VOB file when I select Audio->Main Track.

So, I did 'mplayer -ss 50 mymovie.vob -vc null -vo null -ao pcm:fast'. Fed that wav file to avidemux, adjusted the frame rate of the video to FILM (I got that from mplayer), moved the start to 1301 frames into the video, adjusted the time shift for audio and created an AVI. The problem is that I can't keep the audio video in sync throughout the movie. If I adjust the delay to sync a particular part of the AVI, some other parts in the AVI have audio video out of sync.

Without setting FPS of source to FILM, the total time of the audio and video clips don't match and the out of sync problem is worse.

Is there a way I can make avidemux insert "no sound" for first missing audio and then have it use the audio from the VOB file? Currently, it doesn't show any audio in the VOB file when I select Audio->Main Track.

Any other techniques to make audio video sync across the whole AVI?

Will mencoder work better? like inserting null samples for missing audio part and using AC3 audio when it becomes available at 50 seconds?

All this on Gentoo Linux AMD64, avidemux-2.4.3, mplayer-1.0_rc2_p27725-r1.

28th November 2008, 23:28	#1 \| Link
lam_das Registered User Join Date: Dec 2002 Posts: 64	avidemux, missing audio stream, external audio file and out of sync A-V Hi, I have been bumping my head against this for a while and couldn't get anywhere. I hope someone has a solution for me. I created a VOB file with mplayer -dumpstream. The VOB file plays fine with mplayer but audio stream is not found in the beginning. Sometime around 50 seconds (when the production logo and titles start) into the clip, the AC3 audio comes along and plays in sync with the video. No audio video sync problems with the movie's play. Now, avidemux doesn't find any audio stream in the VOB mpeg header and just creates a video file. It doesn't show any audio in the VOB file when I select Audio->Main Track. So, I did 'mplayer -ss 50 mymovie.vob -vc null -vo null -ao pcm:fast'. Fed that wav file to avidemux, adjusted the frame rate of the video to FILM (I got that from mplayer), moved the start to 1301 frames into the video, adjusted the time shift for audio and created an AVI. The problem is that I can't keep the audio video in sync throughout the movie. If I adjust the delay to sync a particular part of the AVI, some other parts in the AVI have audio video out of sync. Without setting FPS of source to FILM, the total time of the audio and video clips don't match and the out of sync problem is worse. Is there a way I can make avidemux insert "no sound" for first missing audio and then have it use the audio from the VOB file? Currently, it doesn't show any audio in the VOB file when I select Audio->Main Track. Any other techniques to make audio video sync across the whole AVI? Will mencoder work better? like inserting null samples for missing audio part and using AC3 audio when it becomes available at 50 seconds? All this on Gentoo Linux AMD64, avidemux-2.4.3, mplayer-1.0_rc2_p27725-r1.