Plz Help Me :( Divx -> mpeg

[WidowMaker]

Okay, first of all im a super noob.....i just started making vcds alittle while ago! i need help converting divx -> mpeg (vcd) the audio goes out of sync half way through the movie this is what i did.....
1) i split the avi file into 2 parts with avichop
2) used vdub to check for bad frames - (bad frames were found) re-saved avi file (direct stream copy audio and video then save avi)
3) rescaned avi for bad frames...none found
4) i used the guide in this forum ( https://www.videohelp.com/divxtovcd.htm ) to extract the audio to wav format and encoded avi and wav files into mpeg1 file using TMPGEnc but when i play the new vid file the audio goes outta sync half way through... is there something im forgetting or not doing right?? any help would be great!! thanks in advance

[DivXExpert]

In VirtualDub convert the audio to uncompressed 44100 first. Then save wave.

If your DivX was a DVD rip, the person who ripped it probably didn't downsample the audio to 44100 from 48000.
Thats usually causes sync problems.

[ZippyP.]

Don't cut your file, use the source range function in TMPGEnc to mark and encode only a portion of the video at a time. You can batch encode to do the whole thing at once. I don't know if it will fix your problem but it might.

Also, I've had bad frames that Vdub just doesn't catch.Try viewing your Avi where it goes out of sync (in the mpeg) to see if you see anything like blocks etc. You can edit it out manually, check the Edit section for how to edit with Vdub.

8)

[WidowMaker]

well i tried it again.....and it still goes outta sync.... there is no specific moment where it goes outta sync it happens gradually!

this time i used the whole avi file

checked it with vdub for errors and resaved avi
extracted the audio in wav format (44100hz, no compression)

is there anything else that will cause this problem??

[ZippyP.]

Gradual sync problems happen when the audio and video durations don't match. Open the video in Vdub and look at the file information, it will give you the video length in minutes and seconds. Now you can take the wav file that you created and stretch or shrink it to match. You can use the Time Warp function in the program Goldwave to do that, it's available in the Tools section.

[WidowMaker]

ahhh...i see! okay my video length is 1:46:28 and the audio is 1:46:08.232 now should i resize it to '1:46:28.232' or '1:46:28.000' or '1:46:28' ??

[antoniosgubba]

You really need to be as accurate as possible....accurate to the nearest second probably wont be good enough. I believe virtualdub gives you the length of the video to the nearest second...but you can work it out exactly by dividing the number of frames by the fps. For example, if there are 98456 frames and it is a 25fps movie then 98456/25=3938.24 seconds, which is 1:05:38.24 (1 hour 5 minutes 38.24 seconds).

[ZippyP.]

I agree. 8)

[WidowMaker]

umm okay.....

time = 1:46:28 (according to vdub)
# of frames = 153168
fps = 23.976

153168/23.976 = 6388.388
sec = 6388.388

6388.388/60 = 106.47313
min = 106.47313

(106.47313 = 1:46:47.313) <- is this right ????

so does this mean the movie is 1:46:47.313 ?? did i do something wrong with the math ?? vdub has the movie as being 1:46:28 ...i dunno im confused some one plz help me

[WidowMaker]

arrgggg

[antoniosgubba]

No no no no noooooooooooooooooo!!! lol sorry...but you've fallen into the classic trap here! Your calculations were fine until you got to the stage of converting back to mins/seconds.

You got 106.47313 minutes ....which is correct...BUT that is NOT 1 hour 46 mins 47.313 seconds!

What you have is 106 minutes and 0.47313 of a minute....as a minute contains 60 seconds you must multiply 60 by 0.47313 to get seconds.

0.47313x60=28.388

So, the length is 1 hour 46 mins 28.388 seconds...or 1:46:28.388

Try that

[antoniosgubba]

By the way...its definately worth while doing this calculation..because if you'd just stretched the audio to 1:46:28.000 (what virtualdub rounded it down to) then you'd have had a video/audio difference of 0.388 seconds...which doesn't sound much, but is plenty enough to cause very noticable sync problems.

[ZippyP.]

Good one! I checked the math and thought it was OK but you're right!

[WidowMaker]

IT WORKS!!!!! thanks alot guys for all your help, its finally working correctly....thanks a bunch!! ohh BTW how does the audio and video file size end up being different?? and is there anyway to stop it from happening??? it took me like 30+ mintues to time warp the audio file (was the most uneventful time i have spent on the computer ) :P 8)