How to change frame rates using Avisynth with audio in sync?

[digicube]

I have some Divx/Xvid files with unusual frame rates such as 19.2 fps, 24.3 fps, 30 fps. I need to convert them to NTSC compatible frame rates such as 23.976 fps or 29.97 fps while keeping the audio in sync. How can I do this with Avisynth? What are the command lines? I'm gonna use the scripts with CCE to convert to MPEG-2.

[johns0]

AssumeFPS(23.976) or AssumeFPS(29.97) You`ll have to change the audio also,with besweet it would be custom setting such as change frame rate from 19.2 to 23.976,might crash on some setting tho.

[digicube]

Which one is better for Divx/Xvid. AssumeFPS, ConvertFPS or ChangeFPS? Or they pretty much do the same thing.

[johns0]

Not too sure about the others but the one i use keeps the picture at a smooth rate so i believe it changes the fps but keeps the framerate motion the same.

[duhmez]

if the framerate is way off, yo must use convertfps instead of assumefps.

if the source was 19 fps and you made into 29.97, it would be super fast and all whack. If it is really close to 23.976 or 29.97, then by all means assumefps is the way to go.
avisource("movie.avi").assumefps(23.976, sync_audio=true)

Then save out a wav using audio conversion in vdub,. or bewsweet or soundforge or cooledit or........., to 44100 for vcd/svcd or 48000 for DVD.

this will only work perfectly if the audio and video are already already the exact same length.....