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DrFresh
27th August 2003, 14:08
I've searched everywhere. Seen a few questions like this but no answer.

I have some avi's split i two (ore more) with ac3 sound. No matter how I join them, audio alway get out of sync pass the joinpoint. I've used VDubMod to join just the two avi's. I've tried demuxing the ac3's first joining them, and joining the video and then muxing the joined video and the joined sound. But same result. I've also tried converting the ac3's to wav, joining tha wav's, converting to mp3, and muxing again. No matter what I do, I get the same results. I've noticed though, that when joing the wav's, there seems to be a few ms of silence at the joining point. I've tried deleting that too, but it didn't get any better.

Does any one have some ideas to how to do this? Can one use avisynth, opening the avs in VdubMod, and use direct streaming? Or some other idea?

It's really anoing this problem, and I think alot of people would be helped by an answer to this.

Many thanks in advance

Dr. Fresh

alexnoe
29th August 2003, 22:41
If the stream lengths do not match, then AVI won't work, unless the delay at the joining point is compensated.

With output as MKV, it should work. I've tried it with 22 AVI files, each containing one episode of buffy, and it worked perfectly (muxing with (still under construction-) avi-mux gui).

I don't know if VDubMod will do it as well, though.

DrFresh
1st September 2003, 09:30
I'll give Avi-mux-gui a try.

But how do you determine the delay at the joining point? If it's measureable then it's no problem to compensate for that.

Has it got something to do with bad cutting of the avi's or what?

Sorry but what do you meen by MKV?

Thanks

Dr. Fresh

alexnoe
1st September 2003, 09:46
MKV = Matroska (see new a/v forum)

You cannot determine the delay at the joining point easily. You would have to find out the total length of audio in the first file (either in milliseconds or in bytes; the last one is possible in avi-mux gui as well)

kl33per
3rd September 2003, 13:02
muxing with (still under construction-) avi-mux gui
Thank God for this program, I've been using this for muxing AVI's with AC3 sound for ages. And now it's got Matroska support, brilliant.