convert 12,5 fps to 25 fps

[Firk99]

How can I convert an divx-avi from 12,5 fps to 25 fps without loosing audio-video sync. I was thinking at doubling each frame but don't know an easy way to do that.

thanx

[Firk99]

Nobody knows ?

[erratic]

Avisynth should be able to do it: check out the ChangeFPS and ConvertFPS commands: http://www.avisynth.org/FPS

[junkmalle]

Ulead Media Studio Pro can do it.

[jimmalenko]

VirtualDub can do it.

Can I ask why you need to change it to 25fps ?

[Firk99]

I already tried vdub but the audio-video sync was gone.
I need to convert it to make a standard pal video (my standalone doesn't like non standard fps).

[junkmalle]

Be sure to use the right frame rate setting in VirtualDub. On the Frame Rate dialog use the one at the middle right "Convert to fps". That one will simply repeat each frame twice when going from 12.5 fo 25 fps.

If the audio still gets out of sync try turning on full audio processing.

[jimmalenko]

Be sure to use the right frame rate setting in VirtualDub. On the Frame Rate dialog use the one at the middle right "Convert to fps". That one will simply repeat each frame twice when going from 12.5 fo 25 fps.

If the audio still gets out of sync try turning on full audio processing.

Agreed. There are two convert fps options in VDub. I think one rearranges the frames at the new frame rate and shortens the video to a new duration (in your case half as long as it should be), and the other one inserts frames but keeps the same duration. It sounds like you used the wrong one.

Is it a drifting audio problem or a constant delay ?

[barneystorm]

Wouldn't it be better to strip the audio out of the original file first, then convert the video to 25fps, then re-mux them?

[jimmalenko]

Wouldn't it be better to strip the audio out of the original file first, then convert the video to 25fps, then re-mux them?

I don't know whether it would be better.

6 of 1, half a dozen of the other I reckon.

Same shit, different smell.

[barneystorm]

Not really, because you are fixing both parts separately. By doing them together, it's more likely to throw the audio out of sync. Get the video right, then the stripped audio should fit perfectly

[jimmalenko]

Not really, because you are fixing both parts separately. By doing them together, it's more likely to throw the audio out of sync. Get the video right, then the stripped audio should fit perfectly

At the end of the day, if you do it properly, you should not have any issues doing them together.