best free tool to change fps of avi (and add new audio)

[thedarkness]

I think this may have been asked before, but I am wondering what the best tools are now to change the fps of an avi, and add the correct audio to it?

I have been told that virtualdub and virtualdubmod are too old and the ones to avoid as they doesnt work very well in frame rate adjustment, so what is out there that does a better job? I am converting an avi I made myself from 23 fps ntsc to 25 pal. I managed to use besweet to change the audio to 25, but now I need to add this audio to my video, which needs to be at 25fps. thanks for any help!

[AlanHK]

Avidemux

Open the AVI.
Menu: Video/framerate and choose your new frame rate.
Video set to default "copy".
Save as a new AVI file.
This is very fast, so it can't be reencoding.

You can also try the audio filter to convert that at the same time:
choose the format (eg MP3) and then Audio/filter/framerate

Or you can mux in your new audio track.

[redwudz]

Not too sure where you heard that info about VD and VDM. That's all I use most of the time. Something newer might be AVIDemux.

Audio doesn't have a framerate, only length. You can adjust the length with a program like Audacity to match the length of your video.

Usually video framerate changes are done by duplicating or dropping frames. That may give you some stutter in the video.

[jagabo]

I have been told that virtualdub and virtualdubmod are too old and the ones to avoid as they doesnt work very well in frame rate adjustment

Frame rate adjustment works perfectly in both VirtualDub and VirtualDubMod. VirtualDubMod (a modification of VirtualDub) hasn't been updated in quite a while. VirtualDub is up to date and a new version is released quite regularly. The last release was about a month ago.

VirtualDub's advanced audio filtering also supports audio stretching, both with pitch shift, and without.

[thedarkness]

thanks for the replies - i will try avidemux and compare
Ive just found this as well :- http://www.animemusicvideos.org/guides/avtech/amvappvdubmod.html
their guide on avi :- "Frame Rate... This is another option you will never want to use. Firstly the VirtualDub framerate setting isn't very sensible or stable, so it shouldn't be used. If you want to do any frame rate changing you should use Avisynth or AVIfrate which comes in the AMVapp."

Perhaps the problem they thought they had was in stretching the audio, and it was going out of synch with a video they had changed frame rate with for testing...I tried their own AMVapp, but it wasnt really an app, it just installs multiple tools I already had, along with its own AVIfrate. How do Avidemux/Avisynth and AVIfrate compare with Virtualdub/Virtualdubmod for changing frame rate???

[AlanHK]

How do Avidemux/Avisynth and AVIfrate compare with Virtualdub/Virtualdubmod for changing frame rate???

Avidemux works perfectly well, it doesn't re-encode the video, just speeds it up to 25 fps.

I just converted a 44 min 23.976 fps video to a 42 min 25 fps video, worked fine.
Doing audio filtering at the same time took several minutes longer, (as the audio did have to be resampled and reencoded) but it ended up in sync.
You can also choose an external audio file under its audio menu if you prefer.

Avisynth will work, but using that you unavoidably reencode video.

I don't know how VDub does it.

[thedarkness]

trying avidemux right now, the video was set to "copy" with its fps changed to 25 fps- but its original audio track is not in synch. how can I get it to "speed up" the audio as well, so that it stays in synch with the video? Is this what the "time map" option is for?

[manono]

I don't know how VDub does it.

Just as you described for AviDemux - it simply speeds it up or slows it down. I read the section to which thedarkness linked over at animemusicvideos.org and don't understand why the writer said that. I've used VDubMod several times for changing the framerate with no problems.

[manono]

trying avidemux right now, the video was set to "copy" with its fps changed to 25 fps- but its original audio track is not in synch. how can I get it to "speed up" the audio as well, so that it stays in synch with the video? Is this what the "time map" option is for?

I thought you said you already speeded up the audio in BeSweet. Weren't you planning on using that one instead?

[Calidore]

I have been told that virtualdub and virtualdubmod are too old and the ones to avoid as they doesnt work very well in frame rate adjustment

Frame rate adjustment works perfectly in both VirtualDub and VirtualDubMod. VirtualDubMod (a modification of VirtualDub) hasn't been updated in quite a while. VirtualDub is up to date and a new version is released quite regularly. The last release was about a month ago.

VirtualDub's advanced audio filtering also supports audio stretching, both with pitch shift, and without.

I'll second this. I use Virtualdub to convert PAL framerate/audio to NTSC all the time, and it works perfectly. Also, using separate programs to convert the audio and video seems a recipe for sync problems.

Best,

Calidore

[thedarkness]

trying avidemux right now, the video was set to "copy" with its fps changed to 25 fps- but its original audio track is not in synch. how can I get it to "speed up" the audio as well, so that it stays in synch with the video? Is this what the "time map" option is for?

I thought you said you already speeded up the audio in BeSweet. Weren't you planning on using that one instead?

thanks for all the replies... yes, I did stretch the audio to match 25 fps in besweet before, but I just wanted to see if it was possible to do it in avidemux as well, to compare and see which one did the better job - if I could really tell the difference In avidemux (using the rebuild feature or not) I dont seem to be able to get the audio in synch with the video, using the build feature or not, when the source (both audio and video) is from the one original file. Is there something else Im forgetting to do when changing fps, in order to keep audio in synch? The preview feature is helpful

[AlanHK]

trying avidemux right now, the video was set to "copy" with its fps changed to 25 fps- but its original audio track is not in synch. how can I get it to "speed up" the audio as well, so that it stays in synch with the video?

I explained that already.
Twice.

Is this what the "time map" option is for?

No. That helps keep VBR audio in sync when editing.

[thedarkness]

zZzz.. Ill try and stay conscious! thanks for that