Changing framerate without recompressing

[Gjert]

Hi,
I have about 200 short clips encoded with MJPG at various framerates.
I need to set the framerate of all the clips to 25 fps, without loosing or adding frames, and I'm looking for a way to do this without having to recompress them.
I will not be using the audio so it does not matter it it is affected in the prosess.
Does anybody have a tip on a soft that lets me change the fps setting in the header of the files without changing them otherwise?
Thanks :)

[guns1inger]

virtualdubmod will allow you to change the framerate while still in Direct Stream Copy mode. Might be worth a test

[Gjert]

Thanks, I'll try that :)