How to Speed, Slow, and Reverse iMovie Video Clips in iLife ’11
In iLife, iMovie offers Slow Motion, Fast Forward, and Instant Replay options on its Clip menu. To use these options, select the video clip in the Project Browser, choose File→Optimize Video, and then choose Full – Original Size or Large (960 x 540). What optimization does is convert the video using the Apple Intermediate Codec, which makes a bigger video file, but one that can be modified for speed or reversed smoothly. The Full choice preserves HD resolution (or whatever the original size was).
Optimizing the video converts it to Apple’s native editing format. The iMovie conversion is quick, but the video quality is a bit degraded. To ensure that your original clip isn’t converted, iMovie copies it first to a folder within the iMovie Original Movies folder in the Movies folder inside your user folder. You can then import the original clips again from that folder if you want to use them again without speed adjustments.
After optimizing the video clip, choose one of these commands:
Clip→Slow Motion: Then choose 50%, 25%, or 10% (the percentage to slow it down).
Clip→Fast Forward: Then choose 2x, 4x, 8x, or 20x (the multiple to speed it up).
Clip→Instant Replay: Then choose 50%, 25%, or 10% (the percentage to slow down the instant-replay copy of the clip).
The Instant Reply option extends the clip by copying the video and then slowing down the copied video, just like an instant replay in a sports broadcast.
To apply a special effect on a copy of a project clip and still play the original version — for example, to follow a normal clip with the same clip in reverse — select the project clip and then Option-click and drag the clip to a new insertion point in the sequence. iMovie copies the project clip.
To set a more precise speed for a project clip or set it to run in reverse, follow these steps:
Select the clip in the Project Browser, and then double-click it.
If you see the Convert Entire Clip button, click it.
If your video was recorded in a format other than iFrame Video (the native iMovie format), or if it needs to be optimized, the Speed section of the Clip pane shows the Convert Entire Clip button.
After you convert the clip (if it was necessary), the Clip pane shows the Speed settings.Change the speed of a clip or run it in reverse.
Drag the Speed slider to the right (toward the Hare icon) to speed up the clip, or to the left (toward the Tortoise icon) to slow down the clip.
Click the Reverse option for Direction to run the clip in reverse.
Click Done to finish.
When you change the speed of a video clip, the sound’s speed also changes, which can be irritating for recorded voices. And, when you reverse a clip, recorded voices may sound like The Beatles at the end of the song “Rain.” Nature sounds, however, may sound fine backward or forward, or even a bit slowed down or sped up. If you don’t like how a clip sounds, you can adjust the audio portion and even add a different soundtrack.