audio gap field in TMPGEnc

[Lee2595]

If I have a movie that in the avi file the audio is slightly out of sync (the lips move and the sound comes right after) can I adjust this in TMPGEnc by changing the audio gap field? If so would I minus mseconds in this case or add mseconds. I'm thinking - so the audio goes backward with the lip movement but have never used this, Any help would be appreciated

[Don2050]

yes, you can. only do a small clip, ie...1 minute, so you can guage the gap. then you will know.

[narked]

dont do it it TMPGenc, u will waste time farting around doing encoding. Open avi with virtualdub and go to audio - interleaving. Put in figures for audio skew correction and press play. Can see the correction before encoding.

However try not to get too mathematical about the figures as the audio headers are looking for keyframes in the video to sync too. Try putting in multiples of 250ms for correct syncing.

If you've got lengths of corrupt data work out the length the of corrupt data in seconds (how many frames u lost to the next working keyframe) and put in that figure for the audio skew (this is not exact due to keyframes being on average 2s apart and audio headers being 0.5s apart, depending on the codecs used, some divx codecs have keyframe inervals of 300frames, a real pain). Gives a ball park figure (the larger the length of corrupt data the larger the error e.g. recent film lost 20 seconds of movie, calculation out by 2.250s)... then mess with the 250ms +- until get it right.

Keep telling myself I'm going to do the math on this any day now and then avoid it ....