When exactly to use Inverse Telecine?

[SioniK]

The divx-digest guide on encoding from DVD to Divx states that the file would require IVTC conversion "if the Video Type is FILM for less than 90% or is NTSC". Could someone plese clarify what exactly does inverse telecine mean and when should it be used?

[HDRed]

The term "FILM" is another way of saying 23fps. NTSC material is always 29.97fps, so what they mean by that is if your movie is either NTSC or FILM at less than 95%, you should use the inverse telecine command to change the input format (29.97 frames per second) to the output format of 23fps.

Does this clear it up for you? I just learned about this myself.

[SioniK]

I got most of it, but the main thing i always get confused by is the statement "NTSC or FILM at less than 95%". I always thought that IVTC is always needed for NTSC.

[khp]

Originally posted by SioniK
I got most of it, but the main thing i always get confused by is the statement "NTSC or FILM at less than 95%". I always thought that IVTC is always needed for NTSC.

Yes, that is probably true most of the time. I suppose that some "Made for TV" movies or series, might have been recorded at 29.9 fps, in which case IVTC should not be preformed. But I have to admit that I probably have less experience with this than you do.