change duration scaling both video and sound

[jalea148]

Have mp4 [also in AVI] slightly over 1 minute. If the frame rate is changed from 30 fps to 31 it will be under 1 minute. What is the easiest way to do this? [I do not want to clip anything]
Note: have Avidemux 2.6.10; could not find menu items shown in Youtube about changing duration for 2.5.4.; also have Handbrake. I can separate the audio from video and presumably treat each individually. But, I'm concerned they will be out of sync after rejoining. I still don't know the best way for the video.

[sambat]

FWIW, I've done this using VirtualDub.
Assumes the avi is xvid, mp3 128,cbr and the xvid and lame codecs are installed.
Load the video.
Video > Full Processing > Smart Rendering > Compression > XviD
Video > Framerate, Source rate adjustment, 'Change framerate to' and insert the desired framerate.
Framerate conversion, 'Convert to fps' and insert original framerate.
Audio > Full processing mode > Compression, select Lame and use original settings.
Use advanced filtering > Filters..
Add > by double clicking > input, timestretch, output
Double click on the timestretch box and insert the value obtained by dividing originalfps/newfps (should be less than 1) eg 25/30=.833333.
The new audio will keep the pitch and sync with speeded-up video.
OK back to main screen.
Save the video.
With smart rendering I find the output is slightly than without it.

[jalea148]

Thank you. This is the type of answer I appreciate. I downloaded Virtualdub 1.10.4. I got thru everything up to Audio where I have a problem [ Audio > Full processing mode > Compression, select Lame and use original settings.] Lame is not in the list and there is no option to use original settings.

[El Heggunte]

Lame is not in the list and there is no option to use original settings.

Did you install the LAME ACM package
Also, the 32-bit codecs can be used only by the 32-bit applications

"MPEG Layer-3" means Fraunhofer's MP3 stuff. You might want to read the article below:

http://www.komeil.com/blog/enable-fraunhofer-mp3-l3codecp-acm-windows

[sambat]

For 64 bit Windows , place the extracted Lame folder in c:\ and follow the instructions.