Audio synch prob's

[nexus123]

I'm trying to convert full length movies mostly divx to fit onto cd's to be played in a dvd player that supports vcds. I've followed the guide thats located on this website extracted the audio to wav and then used tmpeg to convert the file with the suggested settings matching the frame rate as close to possible. Usually near the end of the first cd or in the case of one of the movies through nearly the entire movie the audio gets really out of synch, like an old kung fu movie, anyway has ne1 had similiar problems that they have worked through. I've had good success with smaller divx files i.e 20 minute episodes of the simpsons which burned fine looked good and I was getting around 7 episodes per cd with no audio problem. Also with one of the movies that I was burning the audio didn't lose synch until the second cd so could it possibly be within the splitting process sometimes I use tmpeg's source range to split I've also used easy video splitter. Do you think that maybe if I split the divx file then extraced the audio then converted it might help some of my audio synch problems.



Thanx -


-=_-NEXUS- _=-

[Hardcoreruss]

Have you checked your file for bad frames ?

[mats.hogberg]

This kind of probs are the worst to deal with. In my experience, they are caused by either bad frames in the AVI or an improper "frame rate conversion" or extracting the audio before encoding.
I'm not really with those who advocate extracting the audio as a default step - this is only necessary when some application in the chain from source to final product can't handle the audio as it is. VBR audio, or AC3 encoded audio are 2 such occations. The downside of extractin the audio is that the audio/video offset in the source is lost, resulting in sync problems (constant thruout the movie). Of course, this can be fixed by adding/removing a little at the start of the audio...
There's a (maybe many?) guide for removing bad frames and retain sync here, and I've tried it a couple of times with bad results. No matter how hard I've tried, where the frames are removed, the sync goes.
Frame rate conversion sync probs can mostly be avoided by encoding to the exactly same frame rate as the source. If the source is in some odd frame rate (not NTSC, not PAL) - Try find a better source...

/Mats