DVD to AVI/MPG etc problem ... Interlaced? What on earth?!

[Rendezvous]

Hi there, everyone.

I'm in the process of trying to author a DVD - but I want to use the credit & intro sequence from an alternate source (a U.S. DVD of the same film).

I've managed to rip the alternate DVD in it's entirity to my harddisc using DVDDecrypter - which all went fine. If I use PowerDVD or Media Player Classic to open all of the DVD files to watch the movie, again, it all looks fine.

If however, I open the individual VOB file in which the section of video I require is stored (be it PowerDVD, Media Player Classic or VirtualDubMod), something odd happens:

The main section of the movie is fine (unfortunately redundant, 'cos I don't need that) - but during the intro & credit sequence at the end of the film, the video alternates between the U.S. english sequence & the Japanese language sequence every 36 frames or so. These aren't subtitles - this is video.

I tried simply manually deleting the frames I didn't want from within VirtualDubMod, which was acceptable for the intro - but not for the credits, as they appear to be properly interlaced at times (i.e. every 35th/36th frame will be an interlaced image of both the Japanese & English image) and I don't want to skip frames if at all possible - and I suspect I might be actually be losing 50% of the image by doing this process.

As a complete newbie with regards to this kind of thing, I'm assuming that the information concerning how these frames should be displayed is lost by opening the individual VOB files - but I don't know how to preserve this information when transferring the video to AVI or MPG etc.

If anyone has any insight that I might benefit from (other than where to stick my DVD), I would be most grateful! Thanks in advance.

[Rendezvous]

Prob solved.

It transpired that the two video tracks were stored as different 'viewing angles', that were active depending upon which audio track you selected. Quite why the two video streams appeared to be spliced together, I don't really know - suffice it to say, using an alternate method of extraction solved the issue outright.

I used SmartRipper to independently select & extract the specific angle/stream - as opposed to the entire movie. Subsequent editing of the file it gave me was problem free ...

Thanks again to anyone who took the time to read (and to rmn over at dvd-hq.info for pointing me in the right direction).