avi audio sync probz

[kandiman]

Hi all, i have an avi file 90mins long captured off satellite, when i load it in vdub the audio is out of sync.

My main goal is to throw it in tmpg and then author it to dvd.

My question is with the audio being out of sync in vdub should i correct this problem before encoding it in tmpg?

I'm not quite sure how to check or if i have dropped frames in the avi file :S

Plzzzzzzzz help

[Chief Engineer]

My question is with the audio being out of sync in vdub should i correct this problem before encoding it in tmpg?

Yes, you MUST correct sync problems before authoring.

I'm not quite sure how to check or if i have dropped frames in the avi file

In Vdub select "Video" ---> "Scan Video Stream for Errors"

Also, in general there are 2 audio sync issues which require differing fixes, a fixed amout throughout and a gradual loss of sync.

[kandiman]

aaah many thx for the reply, so once i check for errors they should be fixed automatically?

also when i output my file in vdub for tmpg should i
go to video--->direct stream copy and audio--->direct stream/no audio...and save as avi to get an avi with no audio?

then video----->full processing---> and audio--->full processing--->source audio.....and save as wave?

So that i have an avi and wav file would this be correct?

[Chief Engineer]

aaah many thx for the reply, so once i check for errors they should be fixed automatically?

Yes, as I understand it.

With the right codecs loaded, TMPGEnc should be able to encode the file with no other processing needed.

[johns0]

Check here if you still have sync problems.

[kandiman]

thx for the replies guys

i noticed that my avi and wav file when loaded in vdub i used interleaving of 300 and the first 30-40 mins are perfect then gradually it loses sync

i read the page you linked me too johns0 ....is the "audio skew correction" hard to do or is it fiddly??

[johns0]

Its not hard to adjust the skew,just input another value and press the input playback on vitualdub to see the change,you can keep changing the value without saving and without having to close and reopen the program.Just save after you get the right sync,as to gradual sync i explained in the guide how to fix that,with bad frames the audio might go off in another part of the audio,this is harder to repair cause you have to find(visually) where the bad frames occured,the easiest way is the play parts of the file and stop at the part where the sound goes out of sync and check around that spot,if you spot bad frames then it means the audio looses sync and you will have to add a few second of audio in that spot,this has to been done with an audio editor,i use goldwave for this type of problem.You have to be precise in how much audio you add so it syncs correctly.If the sound is perfect in sync for 40 minutes and then gradually goes out of sync then you need to cut the portion of audio that is effected and time stretch or shrink it with goldwave or soundforge etc then reinsert back into the audio right at the part where you cut and save and then load the video into virtualdub and the wav into the audio/wav audio and preview playback and check to see if it stays in sync all the way through,you mught have to do some more sound editing if its not quite spot on,this type of sync repair is the toughest but it can be done with patients and if its worth doing.