Audio not in sync with Video stream.

[RabienRose]

Hi all, its be again... yes I know I always get new problems when I fix the old ones. Managed to get my dvdwriter working again, and burning workable dvd-videos......

but now..

1) When I burn dvd-videos, there is an audio lag, or rather the audio stream isnt in sync with the video when played on a standalone dvd player.

Method of authoring for this:

Using tmpgenc dvdauthor. But first demuxing the vobs, into both *.m2v and *.ac3 . Brought into tmpgenc dvdauthor, selected the m2v files and audio files and blah blah. Added menu and authored. Burnt using Nero, tried on standalone player, menu worked, (well not really, except that I couldnt select any of the chapters using the numerical pad, not sure if this is the problem?) video and sound plays, but just that they arent in sync, video is faster than the audio.

2) Tried another authoring using dvdIT.

Method of authoring:

Demuxing the vobs into *m2v and *pcm using Rejig. Re-encoded pcm audio files itno ac3 (320kbps,48000khz), and bringing the m2v and ac3 into dvdIT. Created menus etc, and authored. Burnt using Nero, and tried the end-product on a standalone dvdplayer.

However, this time, sound is STILL not in sync with the video. And worst off, there are lots of "noise" in the sound playback those "ziii zaa zii zap" thingys. Video graphic is fine though.

Any ideas how I can solve this please? Sorry to trouble again

[Tommyknocker]

You could convert the audio into wave with Virtual Dub mod, or an audio editor.

[Barnabas]

You are dropping video frames, so the video is shorter than the audio by the end. You are likely capping from video tapes. No easy fix. Buy yourself a TBC time base corrector, get a better VCR, and capture via VirtualDub with "drop video frames" setting.

[RabienRose]

Hi tommknocker: thanks for the reply. I tried capturing the wave of the vob using VirtualDub and then re-encoding them into ac3 (48000khz,320bitrate) with the same results. End product has audio out-of-sync with video stream.

Barnabas: actually Im not capping from video tapes, in fact, they are vobs or direct rips from a dvd.

Is there any ways to solve this problem of audio out-of-sync problem?

thanks

[dafreak]

just curious. Why are you demuxing the vob files in the first place. Why not burn the vob files as is?

there really isn't a reason to demux audio and video unless maybe you have non-compliant dvd audio stream. Sounds like you might be adding an unnecessary step.


if you really need to demux the audio. You might want to try correcting the audio file using beslice.

[RabienRose]

Im demuxing the vobs, because well I think there MIGHT be a problem with one of the files and I do not know which one is it. So might as well demux them all

I realised I have this problem, when using VOBEDIT > JOIN CLIPS , an extra chapter appears. Meaning I have , say, 18 vobs, so that would come up to 18 chapters, but the finished product after using vobedit turns out to be 19.

However, that really doesnt matter, by using which ever methods I've learnt they end up having the audio out-of-sync anyways. Anyway to fix that? thanks a lot

[BobK]

I use TMPGEnc DVD Author and I have to all video in segments of 15 minutes or less. If I use segements longer than 15-20 minutes then the audio gets out of sync no matter what I do.

[Barnabas]

I would try it with out muxing, since you simply *think* there night be a problem.

I do video conversions, and fixing a file that is gradually out of sync is usually MUCH more trouble than it's worth. If the sync is off by the same amount from start to finish, that's easier to fix, but the gradual type is not really fixable unless the amount it's off is small. There are guides in the forum that will show you what's involved with trying to fix audio sync.

[dafreak]

I got a question. When you're remixing the two files together are you changing the frame rate of the video at all? ie. going from 25 fps to 29.97?

[RabienRose]

Hi all, thanks for your replies again.

Bobk: all the vobs/clips I am compiling are max 6mins long.

Barnabas: I have tried compiling them without the muxing part, ends up with the same problem, the audio is out of sync as usual, do you think I might have left out some settings somewhere? Will try scouting in the guides area and checking out for possible solutions in the meanwhile too.

dafreak: Hi, actually while demuxing the vobs, I used Rejig to demux the video stream, and virtualdub to save the audio stream as wave from the vob files. Are there any settings I should be aware of that might cause the audio out-of-sync? Or, is there any "proper" guide to demuxing files? Would appreciate it lots.


Thanks all!