Why to use the "telecine" filter on DVD-VCD conversion?

[hmedina]

I read vcdhelper guides to rip DVD's and also read an extensive guide on DVD ripping to VCD on a very complete page on flexion, which recomends to apply a resize filter and a telecine filter (if source is NTSC (?)) on Virtualdub and then frameserve to tmpgencoder. I made a test to compress the d2v created by dvd2avi directly to TMPGEnc12h and I got excelent results (and in almost half the time). It looks good even on a 41 projection TV, for VCD. What is the use of aplying the telecine filter in the process? Am I missing frames or something?

Thanks!

[hitechjunkie]

if your source is 23.97fps and purely progressive, then i don't see any need to apply any telecine filter to reconstruct frames (and fields?) and bump it up to 29.97fps. unless of course your player has a problem with 23.97fps...

[hmedina]

But what if the source is already 29.97? Well, I think if DVD2AVI reports that the source is NTSC, then it means that it is at 29.97, am I correct? Should I convert to other framerate for VCD?

Thanks

[hitechjunkie]

if the source is 29.97fps, you could apply inverse telecine to get it back to it's original filmrate of 23.97fps (assuming it was 23.97fps originally), but inverse telecine is a tricky thing since not all telecined material is the same. try a "standard" IVTC filter and if you wind up with a smooth, progressive 23.97fps video, then you got lucky and can use that to encode to VCD. otherwise, it probably not worth the trouble.