audio video sync

[thecrock]

I have a large avi file i want to burn to dvd but when i do, the audio is a second or two out of sync with the video. The file was originally in two parts and i used easy video joiner to merge them. The picture quality is great and the audio sounds fine it's just out of sync. I use nero to burn to dvd, should i try something else. Any help would be most welcome.

[echooff]

Is it out of sync the same amount throughout the movie. If so, you can use either virtualdub or virtualdubmod to adjust the audio under the interleave function. You can set the audio to play sooner or delay. Play with the adjustment and once it is to your liking, make sure the audio and video is on direct stream copy and save it under a new name. If it is not the same throughout, but jumps after the join, you will need to repair it prior to joining.

[thecrock]

No the audio is not out of sync throughout the movie it starts off fine then gets steadily worse until after about twenty minutes it's two or three seconds out. I have just downloaded virtualdub thanks for taking an interest.

[echooff]

Check the time duration of both you audio and video. Open the file in vdub and look at file information. I suspect you will find the audio is much shorter that your video. You will need to time stretch the audio to fix the problem. It depends on your audio application how this is done. Adobe audition has a function called time stretch. It may be called something else in others.

Edit: If your audio format is ac3 it is much more difficult.

[specnaz]

I have a similar problem. I appended two avi's with virtualdubmod and now when second clip starts audio is out of sync. I checked the video and audio lenght and they are different. Can I use like adobe audition to strech it. Only problem is my audio is an ac3 5.1. Can someone help me out. Thanks

[thecrock]

I just read a guide for setting audio parameters in virtualdub, I haven't got the time to mess with it at the moment. Go to this page and tell me how you get on http://nickyguides.digital-digest.com/join-split-avi.htm
cheers everyone.

[specnaz]

Thanks, that guide helped. And i did not had to mess and uncompress ac3 file. One more question what to do if for example the audio file is longer than video, is it possible to strech the video or you have to cut the audio in virtualdub? and what if audio is an ac3?