How to change 30 fps to 29.97 fps ?

[pchan]

Hi All,

I have an uncompressed AVI file 720x480 30fps. I would like to make this video clip DVD compliant. So, I use VirtualDub to change the frame rate from 30 to 29.97 but the audio is out of sync. How to change the frame rate without causing the audio out of sync ?

If VirtualDub cannot do it, then what software can do it ?

Thanks in advance.

[pchan]

I have found the answer in post#5 of this thread.
https://forum.videohelp.com/threads/290395-How-to-convert-a-video-of-120-Fps-to-well-23...-fps-or-30-fps

[jagabo]

Changing the frame rate from 30 fps to 29.97 fps using the Convert option in VirtualDub will throw out one frame every ~33 seconds. That can sometimes be noticeable as a little jerk during playback. Slowing the video from 30 fps to 29.97 fps will give smoother playback but requires the audio be slowed too.

[sambat]

Changing the frame rate from 30 fps to 29.97 fps using the Convert option in VirtualDub will throw out one frame every ~33 seconds. That can sometimes be noticeable as a little jerk during playback. Slowing the video from 30 fps to 29.97 fps will give smoother playback but requires the audio be slowed too.

I've used that method to get a slow motion file with the audio stretched to fit.
In this case, keeping video 'Direct Stream Copy' and using Source Rate Adjustment to change the frame rate to 29.97, you can use Full processing/Advanced filtering in the audio.
Time Stretch filter set 30/29.97=1.001001, then select an audio compressor.

[pchan]

@jagabo,

How to slow down the video and audio ?

@Sambat,

Can do that for Video too ?

[sambat]

@Sambat,

Can do that for Video too ?

That's what I did;I slowed the video - but did not re-compress it.
This made the video play slower, but the audio has to be stretched to fit the new, longer playing time.
The Time Stretch audio filter ensures that there is no pitch change.