Weird frame rate issue. Anybody ran into this before?

[dimtim]

Hey so I'm trying to rip dvd to xvid. I've been using DVD decrypter, DGIndex to separate the audio and video streams, and Vdub to encode to xvid. Sometimes though, DGIndex and Virtualdub will say that an mpeg2 file I ripped has different frame rates. Usually I will open it in DGIndex and it will say 29.70 and then again in Virtualdub and it will say 23.976. I think this is causing audio and video sync errors and I'm curious if anybody has run into this before.

Thanks
Tim

[jagabo]

DGIndex:

Video -> Field Operation -> Forced Film = 23.976 fps in VirtualDub.
Video -> Field Operation -> Honor Pulldown Flags = 29.97 fps in VirtualDub.

Neither should cause A/V sync errors with normal 3:2 pulldown flagged sources.

VOB files often have variable frame rates, especially at the start with the studio logo, etc. This often causes A/V sync issues but can usually be used by using the audio skew setting in VirtualDub.

[dimtim]

Hey thanks for the reply, and that does make sense. When I preview the file in DGIndex the first couple frames it says interlaced, and then, after a couple seconds it goes to film. If I do honor pulldown flags instead of forced film would that correct the error? If not, is there any way to account for this without encoding, looking at the video sync, and then encoding again?

Thanks
Tim

[dimtim]

Oops repeat post.

[jagabo]

Hey thanks for the reply, and that does make sense. When I preview the file in DGIndex the first couple frames it says interlaced, and then, after a couple seconds it goes to film. If I do honor pulldown flags instead of forced film would that correct the error?

Maybe. Why don't you try it? You will probably need to inverse telecine if you do this.

If not, is there any way to account for this without encoding, looking at the video sync, and then encoding again?

You don't have to reencode again. You can remux the audio and video with VirtualDub in Direct Stream Copy mode and use the audio skew function to shift the audio forward or backward.