Correcting Sync on a DVD Recorder Capture?

[Offroad]

Have some concert footage from HDNet I captured with a JVC DR-M10.
They all look great but I have one that the first three songs were in perfect sync, then on the fourth one the sync got way off.

Not sure this was a JVC problem as this wouldn't be the first time I have seen an audio synch issue on Dish Network broadcasts with my 811 STB.

I have split the file using Womble where the problem appears to occur, what tool or process can be used to fix this problem? I want to keep the quality as high as possible with a reasonable amount of work.

The capture was made at SP and so is 720x480 VBR and AC3 at 256mbps.

Thanks for any help.

[normando]

First, demultiplex your vob. Then you can multiplex it in Womble's MpegVCR and adjust the AV-Synch via the button at the bottom of the window.

Are the files out of synch when you playback your DVD+VR disc on your recorder?... or merely on your computer after you rip them?

[Offroad]

Are the files out of synch when you playback your DVD+VR disc on your recorder?... or merely on your computer after you rip them?

Thanks for the response.

The files were captured to DVD -RW formatted in Video mode (VBR video and AC3 audio). The VOB's were ripped to PC with DVD Decrypter in File mode set for no file splitting. I had only trimmed the ends in Mpeg-VCR then saved the stream copy.

I no longer have the files on the -RW as it was put back in use on the recorder. I'm sure I sampled the disc most of the way through and didn't notice any sync problems while playing back on the recorder.

After trimming the ends and saving in Mpeg-VCR I probably didn't play the file much except probably just the first of it. Seems kind of weird that through the first three songs its in sync then the rest isn't.

Anyway, I just demuxed it in Womble, I ended up with a .mpv and a .ac3 file. But when I tried to adjust it and remux it didn't seem like I was affecting the sync noticeably.

Is there some way to measure how far off I am and put that number into Womble during multiplexing? I'm not even sure what the scale on Womble's AVSync adjustment is measured in.

[normando]

The time is measured in milliseconds. Thus a value of -600 would mean it would correct it by -.600 seconds.

Unfortunately, you have to make your adjustmenst by trial and error...

[Offroad]

The time is measured in milliseconds. Thus a value of -600 would mean it would correct it by -.600 seconds.

Normando:

Did some experimentation.
If I demuxed the file and kept the audio as AC3, Womble's Multiplexer would accept the AC3 audio file but no matter what amount of correction I tried there was no change to the sync on the output file.

If the audio file is converted to MpegII and muliplexed in Womble, the values entered actually have an effect. Have to do a bit more testing but looks like about +.500 gets this file in sync.

1. Why won't Womble adjust the sync on AC3 audio even though it accepts the AC3 audio file and the sync correction values?

2. Is there any other program that would work on AC3 audio?

3. How much audio quality is lost in converting the audio from AC3 to MpegII? I assume I'd lose more if I converted back to AC3 during authoring?

Thanks.