Adding ADDITIONAL audio to an avi file

October 25, 2009 3:23 PM

How do I add an additional audio track to a .avi movie file in OSX? I downloaded a full length movie, it had stereo channel audio, but one of the audio tracks was still missing, possibly the center channel that was lost from a surround sound mix when it was bounced to standard 2 channel audio. I now have the missing audio file and need to add it to the other two.

I could just remove one of the existing tracks, or turn the existing two tracks into a mono track and then add the 3rd missing track. It doesn't need to sound amazing...but I don't know what software to use to do this. Any ideas?

posted by Charlie Lesoine to computers & internet (5 comments total)

You can do this in Quicktime 7 Pro, the license key costs around $30. You will have to do the syncing by trial and error, but other than that it is relatively easy to do.

Open the missing audio file and the movie in Quicktime Pro (note, if you are using Snow Leopard, the pro application now lives in the Utilities folder). Use the sliders to select the audio you want to add and chose copy, then use the sliders on the movie file to highlight where you want the new audio to go (probably the whole movie) and then select "Add to file" from the edit window.
posted by DiscourseMarker at 4:30 PM on October 25

I use either Quicktime ($25) or iMovie to add audio to movies. If you use iMovie, all you do add the audio track from the built-in iTunes menu. You then see it as a colored bar that you can physically move to the exact location of your liking.
posted by Piscean at 4:32 PM on October 25

If the .avi file isn't being recognized as playable/editable in Quicktime, you may need to transcode it to a file format that is. Despite it being discontinued, I still use Visual Hub for this. Other possibilities are Video Monkey and Stomp.

Alternatively, you might be able to get Quicktime to play nice with your .avi file by installing Perian which allows it to use more video codecs.
posted by mrbarrett.com at 4:43 PM on October 25

I have no problem opening and editing .avi files in Quicktime without Perian, and it is listed on Apple's list of supported file formats. I do, however, have the DivX player and plugin installed.
posted by DiscourseMarker at 5:10 PM on October 25

The answer under windows is VirtualDub (free), and you might be able to run that from OSX using a virtual machine if you're on an intel Mac.
posted by polyglot at 7:15 PM on October 25