A/V Syc Problems

Question

Hey everybody.
I'm the videographer for one of my school plays, and I'm having editing problems. In order to get better voice recordings from the stage, I used a microphone seperate from that of the video camera. I have had no troubles syncing the audio and video in iMovie at the beginning, but when I shuttle to the other end of a the scene, the audio is roughly fifteen seconds out of sync. The scene itself is about 20 minutes long. I tried slowing down the video to compensate, but a one pixel difference damatically overcorrected the issue. Back to square one.
So then I tried importing the audio into Audacity to see if a could spped it up the tiny amount required. Unfortunately, Audacity seems to be having problems importing AIFC files. I'm unfamiliar with them, too.
I want to try converting the files inside Quicktime Pro, but I don't have it, and my parents won't buy it until someone else says it'll work.

Answer 1

This sounds like you've been using a Canon camcorder, and with the audio possibly set to 12bit (32kHz) instead of 16bit (48kHz).
Canon audio tends to slip out of sync in any single continuous clip over about 20 mins.
You should be able to adjust it with Audacity: try importing again, and just snip off half-a-second of audio here and there - say every fifty seconds or so ..just under every minute.
To edit it with Audacity, just 'Extract' the audio in iMovie. Then do the following:
1 - In iMovie, double-click the extracted audio clip to see what iMovie calls it: ignore the 'Name', but make a note of the 'Media file:' ..it'll probably be called "Extracted Audio 01.aiff". Save your movie and close iMovie.
2 - In the Finder, go to your 'Movies' folder (or wherever you've stored this particular movie) and Ctrl-click (or right-click) on the particular movie's name, and then choose 'Show Package Contents'.
3 - Then open the 'Media' folder, and drag the file "Extracted Audio 01.aiff" (..or whatever it was called..) onto your Desktop or into the 'Movies' folder ..anywhere as long as it's out of the Media folder within the 'Package' which comprises your movie (because Audacity won't be able to find it if it's hidden within the 'package' which comprises your movie).
4 - Open Audacity, and choose File and Open, and navigate to where you've stored that "Extracted Audio 01.aiff", and choose that. It should import into Audacity with no problem.
5 - Do your editing (see below) and then Save and close Audacity.
6 - With the Finder, open that 'Package' which is your movie - by ctrl-clicking or right-clicking on it again - and drop the edited "Extracted Audio 01.aiff" back into the 'Media' folder.
When you re-open iMovie, your edited "Extracted Audio 01.aiff" should play correctly.
When editing it in Audacity, try to snip out a bit of silence just before someone speaks: the very slight resultant lack of sync probably won't be noticeable in the video from where your camera was standing. Try to chop out teeny bits of silence, rather than cutting out actual sounds.
Congratulations on choosing to use an external mic instead of the camcorder mic, though!
Oh, and welcome to iMovie Discussions.