Audio not in sync with video.

[JustSomeGuy]

What can I do with an avi file who's audio is ahead of the video?

[ZippyP.]

Open it in virtualdub, under audio >interleaving >audio skew correction enter a delay time for the audio (+ or -). In the main window you can play the clip, adjust the delay and keep testing it until you get it right. Set both audio and video to direct stream copy, save avi. 8)

P.S. You can frameserve directly it to your encoder rather than saving it if you choose.

[JustSomeGuy]

Does it take a long time to save the file once the offset has been added?
I mean it shouldn't have to recompress everything should it?

[bambam]

n the main window you can play the clip, adjust the delay and keep testing it until you get it right.

Does that mean that you can see in real time your adjustment to correct theaudio sync without having to re-encode the hole file ?

[sacajaweeda]

Pull up the file info in Vdub and check the file lengths of both streams. Offsetting the difference should get you in the ball park. Filters will bog Vdub, as will a weak computer, so those have to be considered when evaluating your results in alleged "real time".

This does not apply for progressive sync probs, especially if you dropped frames capturing and were not using dynamic resampling for your audio.

[ZippyP.]

Does it take a long time to save the file once the offset has been added?
I mean it shouldn't have to recompress everything should it?

No, it doesn't take long. It's not re-compressing, that's what "direct stream copy" does...saves it in the original format.

[ZippyP.]

Does that mean that you can see in real time your adjustment to correct theaudio sync without having to re-encode the hole file ?

You can see your adjustments right after you make them in the main window.

[bambam]

Great thanks