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I am capturing videotaped movies directly to an MPG-1 video file. The finished product is fine, but when I split these movies into CD-sized files using TMPGEnc (for example) the soundtrack ends up out of sync. What the heck am I doing wrong?
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You could use other mpeg splitting software available at divx-digest.com or vcdhelp.com -
When you split a movie always split on a key frame or you stand a good chance of audio/video sync probs.Comment
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OK, what is a "key frame"? Is it the first frame of the file?
The sync problems are always worse the farther I get into the file; when I make a file of the second half of a movie, it's always *completely* out of wack!
I've tried other programs, and the results are always the same: part 1 starts off good but gets out of sync by the end of the file; part 2 starts off bad and stays that way!
Many thanks for the help and suggestions; I'm sure we're going to hit on answer eventually!Comment
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A Key Frame is like the master picture that copy pictures are made from, so yes your first frame would be a Key Frame.
Now we know that if we get a video tape and make a copy of it we get pretty good qaulity, but hen say we make a copy of the copy and then a copy of that copy. Over the time the quality gets worse, wel this is the same with key frames.
Movie compression works by only encoding the bits that move, so say a person is talking with their head pretty still, then we only need to save the data for the lips moving and just keep copying the rest of the scene over and over again (Delta Frames). This gives us the video tape problem above, so another key frame is created using all the scene data which keeps the quality from dropping to low. Also key frames are inserted at change of scenes and action etc.
[ <- Key Frame [[[[[[[[[[[ <- Delta Frames [ <- Key Frame and so on.
Have you ever watched a DivX movie and skipped to a later part then noticed it seems to go double speed for a bit then settle down to normal. Well this is because it has to start from a key frame then build the picture to were you wish to skip to.
So if you don't split on a key frame the movie does not really have a place to start from and this will cause sync problems.
If you checkout this link it will explain Key Frames a lot better than I can:
Also check this too: http://www.divx.com/support/guides/c...hp?cid=2&gid=6
I know it's for DivX movies but it's just to give you a better idea of what I mean.Comment
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