iLife '04: The Missing Manual

Extracting Audio from Video

iMovie is perfectly capable of stripping the audio portion of your footage apart from the video. All you have to do is click the video clip in question and then choose Advanced → Extract Audio.

As shown in Figure 17-13, the recorded audio suddenly shows up in your first audio track as an independent audio clip; its pushpins indicate that it’s been locked to the original video.

Figure 17-13. Top: Highlight some camcorder video and choose Advanced → Extract Audio.Middle: The camcorder audio appears as an independent clip, which you can manipulate exactly as though it’s any ordinary audio clip.Bottom: You can create a reverb or echo effect by overlaying the same extracted audio several times.

This command unleashes all kinds of useful new tricks that weren’t possible in the first version of iMovie:

• Make an echo. This is a great one. Copy the extracted clip and paste it right back into the audio track—and then position it a few frames to the right of the original. Use the slider at the bottom of the Timeline Viewer to make it slightly quieter than the original. Repeat a couple more times, until you’ve got a realistic echo or reverb sound.

• Boost the audio. The Volume slider at the bottom of the Timeline Viewer is a terrific help in boosting feeble camcorder audio. It does, however, have its limit: it can’t crank the volume more than 50 percent above the original ...