stretching or compressing audio to match video?

2 posts / 0 new

Login or register to post comments

Last post

Mon, 05/09/2011 - 15:27

#1

shonangreg

Offline

Joined: 05/09/2011

Posts:

stretching or compressing audio to match video?

I've recorded a friend playing guitar using a digital camera and an mp3 recorder. The audio from the camera is horrible, but the mp3 is great. I used avidemux to cut the video without transcoding and I used audacity to transcode the audio to a flac file and cut it to approximately the same length.

But over 5 minutes, the audio drifts to 7/30 of a second (0.2333 seconds) slower than the video.

Looking at the beginners' tutorials doesn't address this. How can I stretch or compress one or the other?

http://www.kdenlive.org/test-book/first-project/now-video/project-settin...
"It is not possible to resize an audio or video clip past their length - if a clip is 30 seconds in length, then you will not be able to resize the clip so that it finishes playing 35 seconds into the clip!"

Thank you.
Greg

Average:

Your rating: None

Wed, 05/11/2011 - 08:31

#2

al25fps

Offline

Joined: 10/31/2009

Posts:

Re: stretching or compressing audio to match video?

1. audacity can stretch your music, as seen in the feature list of audacity:
"Change the pitch without altering the tempo, or vice-versa."

2. If you have multiple clips you can synch video and audio every minute or so by switching to another clip and skip 1-2 frames - as long as the difference between video and audio is small enough 99% of your audience will not recognize it. If you skip one frame every 14,2 seconds it might work, too.

3. You can see if using the speed effect at 98-99% matches the audio.

Cheers, Achim