
Extracting, Adding, and Moving Tracks
You can create a new movie from one or more tracks of an existing movie, while leaving the original movie file intact. For example, you could create a movie that uses only the audio from an existing movie. To do so, you extract the desired tracks.
You can also add the extracted track to an existing movie.
To extract a track (and add it to another movie):
- Choose Window > Show Movie Properties.
- Select the desired track or tracks and click Extract.
You can select more than one track by holding down the Shift key when you click.
QuickTime creates a new movie containing the extracted tracks.
- To add the extracted track to another movie, select the movie (or the portion of it you want your pasted media to fit into) and choose Edit > "Add to Movie."
When you add a track to a movie, the track's duration is unaltered. For example, if you add a 10-second sound track to a 1-minute movie, the sound track plays for 10 seconds, starting at the position in the movie where you added the track.
To "scale" a track so that it stretches or compresses to a particular length, drag the In and Out markers of the target movie to select the duration you want the new track to cover and then choose Edit > "Add to Selection and Scale" in step 3. Scaling audio may change the speed of the audio (although the pitch remains the same when you play the movie in QuickTime Player). You could add video to sound instead, and speed up or slow down the video to match the audio. You might have better results if you compare the timelines of the two tracks and cut from one or the other until they have the same duration.