Why Go 25 fps to 23.976 fps When You Want 29.97 fps?

[aamir12345678]

Why don't you just convert the PAL 25 fps audio directly to NTSC 29.97 fps? Why is it necessary to convert the audio to NTSCFilm 23.976 & then do 3:2 Pulldown Encode Mode?

[FOO]

The audio needs to be synced to the video at 23.976 because that
is the video frame rate being sent to the video decoder. The decoder
is making up frames to get to 29.97

[SLK001]

When converting from one format to another, it's best to start at the "native" frame rate. Since most movies are shot at 24.000fps (which 23.976fps is, more of less), once you get back to 24fps, moving to the other format is fairly easy.

[adam]

You could convert to 29.97fps if you wanted to, but you would lose alot of quality and since the conversion is so much more complicated you run the risks of getting sync problems, interlacing artifacts, etc...

Most NTSC footage is stored at 23.97fps and converted to 29.97fps on the fly by the decoder. It is much more efficient and much higher quality. Do a forum search for pulldown or telecine to find out why. Depending on the encoder you use I'd say storing NTSC footage at 23.976fps as opposed to 29.97fps is anywhere from 20% to 40% higher quality.