Irritating synch problem

[King-Of-DK]

Does anybody know how to correct this little problem. Every time i convert an AVI using TMPGenc the MPG file is out of synch,it start fine,then as the movie progresses the synch problem gets worse.I use VirtualDub to extract and convert the audio from 48000hz to 44100hz,but sometimes when i load a file Virtualdub says that is has detected an improber VBR and that it may introduce X number milliseconds of skew,and that i have to reencode with a constant bitrate encoder,i have never reencoded the audio and it has worked fine,but lately i get the synch problem on files that virtualdub thinks is fine..to make a long story short,does anybody have a *.VCF file that i can load and fix this problem,or do i really have to reencode the audio?

[Whitey Smails]

Does anybody know how to correct this little problem. Every time i convert an AVI using TMPGenc the MPG file is out of synch,it start fine,then as the movie progresses the synch problem gets worse.I use VirtualDub to extract and convert the audio from 48000hz to 44100hz,but sometimes when i load a file Virtualdub says that is has detected an improber VBR and that it may introduce X number milliseconds of skew,and that i have to reencode with a constant bitrate encoder,i have never reencoded the audio and it has worked fine,but lately i get the synch problem on files that virtualdub thinks is fine..to make a long story short,does anybody have a *.VCF file that i can load and fix this problem,or do i really have to reencode the audio?

I get that problem all the time. I have no idea how to fix it. I've asked here a billion times...but I get a bunch of different answers. Do any experts browse this forum?

[KingJohn]

Vdub gives you this warning, incase you are going to re-encode the AVI to another AVI. Since you are not going to do this, you can ignore the error and save out the audio converted.

Audio > full processing mode
Audio > Conversion > 44.1Khz
SAVE WAV

However, to complicate things, the AVI might have bad frames, which need to be removed before the AVI will be any good. If this is the case then you do need to re-process the whole AVI in Vdub, As streaming type saves will cause lip-syinc.

The latest TMPGEnc can handle bad frames better than before, so there is a good chance that using the uncompressed WAV while encoding to mpeg1, wont produce lip-sync.

Each AVI you download is different, it may need a different approach, one of the biggest problems with audio is not having the correct audio codec's present, AC3 is used quite a lot with DVD rips, and this accounts for a lot of problems.

I would recommend you install the Nimo codec pack to make sure you have all the codec's needed, then proceed as above.

[King-Of-DK]

I am aware of the problems you explain here,i on the other hand have no problems with avis and ac3,i just convert the ac3 with AZID,and it works.I especialy had the synch problem when converting Collateral Damage,but found out that i had to delay audio 14500 ms,in virtualdub when extracting the wav,but this only works when the synch is the same through the whole movie,i still can´t fix the problem where it gradually gets worse throughout the movie..Thanx for your answer by the way

[fofito]

I have a similar problem but mine seems to happen only during the burning process, up to that point the movie plays Ok but once I burn the movie and play it in DVD the audio gets out of sync for a few seconds and them goes back to normal, it can happen 3 or 4 times during the movie the picture and sound quality are great, except for that problem. I'm using Roxio 5.0 platinum. Could it be my CDR? it's old , write speed is 2x(max)

[KingJohn]

Maybe both of you could try a different brand of disks, if the original mpeg works perfectly fine on your hard drive, and its a fully compliant mpeg, then it has to be down to the type of disks your using which your DVD player does not like.

[King-Of-DK]

That is exactly the problem,the MPG file is the one with the synch problem,it happens during conversion.

[Daagar]

I have been having the same troubles as king-of-dk. The original AVI is fine, but when converted it goes out of sync during the course of the movie. Perfect sync early on, but 400ms of delay after about 1 hour (yes, I actually measured it while trying to fix it).

The original AVI claims to be 1:19:07. When I extract the WAV, it claims the file is 1:19:02. The encoded MPEG file claims to be 1:19:06. Obviously, something isn't working right... these should all clearly be the same size. The problem is that I haven't figured out how to make that true.

[KingJohn]

I have been having the same troubles as king-of-dk. The original AVI is fine, but when converted it goes out of sync during the course of the movie. Perfect sync early on, but 400ms of delay after about 1 hour (yes, I actually measured it while trying to fix it).

The original AVI claims to be 1:19:07. When I extract the WAV, it claims the file is 1:19:02. The encoded MPEG file claims to be 1:19:06. Obviously, something isn't working right... these should all clearly be the same size. The problem is that I haven't figured out how to make that true.

Then that sounds like bad frames

[King-Of-DK]

Please read topic,and provide answer if any one can? This post has gotten a little sidetracked with all the dvd players stuff.The fact remains that the problem with the synch happens during conversion from AVI to MPG,and i use an extracted audio file from virtualdub,so if anyone has an idea it would be very appreciated.There was a fix released for Kate And Lepold that cut the movie up and correct the synch problem,is that possible for a file that gradually gets worse?? I have to tell you,that we are talking about a VCD conversion not SVCD,as my player doesn´t support SVCD.

[KingJohn]

Then that sounds like bad frames 8)

[spidey]

If the original wav extraction and encoding is still off, load your encoded MPg into a program like SOnic FOundry Vegas Video.

This then lets you seperate the 2 streams. I then line then up through adjusting the video stream by dragging it, and then preview, in Vegas till they line up.

Then highlight the audio track, in it's entirety, as it is lined up correctly against the begin/end points of the video stream, resave it as a wav or even a mpg (it'll sense it's only audio and make it a mpg layer 2). If you go the wav route, simply encode to mp2 with Headac3he, and then multiplex in TMPG.

Done.

[Daagar]

spidey... I tried something similar to your message using Sound Forge and the 'Time Stretch' processing mode, but Sound Forge couldn't handle it! I had a video that was 1:19:06.838 and I needed to make it 1:19:06.459 to be in sync throughout. However, Sound Forge without fail keeps shrinking it to 1:19:06.119! This does absolutely no good, because now I'm just as far off in the other direction as I was at the start.

Is this Vegas Video tool a bit more precise? This does seem to be the correct workaround, if I could find a tool exact enough to handle it.

What would be really nice is to find out why this occurs in the first place... having to do all this post-process should not be necessary....