iMovie '09 & iDVD: The Missing Manual

Stabilizing Shaky Footage By David Pogue and Aaron Miller Not every piece of video needs fancy effects. In fact, most video is probably better without a Dream filter and Picture-in-Picture. The unadulterated stuff straight from your camera usually looks best. In fact, if your footage needs any help at all, it's probably in the cameraman department. Don't take this personally. Handheld shots, the most common kind of home video, are notoriously unstable, and that's an instant giveaway that you're an amateur. You can have the hands of a surgeon and still end up with shaky footage. This is true even with all the newfangled image stabilization technology that comes in the latest cameras. Don't give up (and don't resort to carrying a tripod everywhere). iMovie '09 can stabilize your video after the fact, using one of its most amazing new features. Video Stabilization iMovie has powers that leave other "beginner” video-editing programs panting with envy. It's filled with tools that have historically been found only in professional editing programs. iMovie's stabilization feature, for example, is inherited from Apple's $1,000 Final Cut Pro software. It works by analyzing every single frame in a clip, recognizing the changes in both camera position (movement up, down, left, or right) and camera rotation. Once it figures that bit out, it knows how to slide and rotate your clips to iron out the shakes. Unfortunately, this sort of analysis takes a very long time—roughly ten minutes for every minute of video (more or less depending on your Mac's speed). The results, however, are worth it. The stabilization feature works absolute magic on most jerky, bumpy handheld footage. It works so well, in fact, that it can look positively creepy, as though you were floating along on a magic carpet. Fortunately, there's a slider that lets you control how much stabilizing goes on. Four Ways to Trigger Stabilization Analysis Before iMovie can stabilize your video, it has to perform the above-mentioned analysis, which takes a long time. Fortunately, you have a lot of control over when the program does this processing: 1) Stabilize during import. You're offered the opportunity to perform the analysis when you bring the footage into your Mac, as described in Chapter 1. 2) Stabilize selected clips. You can analyze certain clips at any time. Select one, or a group of them, and then choose File-->Analyze for Stabilization. 3) Stabilize an entire Event. In the list, click an Event's name and then choose File-->Analyze for Stabilization. This option is great if the Event in question is someone jumping on a trampoline during an earthquake. 4) Stabilize a clip in the Event Browser. Double-click the clip to open the Inspector panel. Click Analyze Entire Clip as shown in Figure 7-1. 5) Stabilize a clip that's already in the storyboard. Point to the clip, and then from the gear-icon menu, choose Clip Adjustments. On the panel that appears, turn on "Smooth clip motion.” This is a great trick when you're looking over a project in progress and discover that one particular jerky shot is ruining the flow. It can also save you a lot of time, because iMovie stabilizes only the 20 seconds of a clip that you've actually used—plus an additional second on either side—rather than processing the 15-minute original (see Figure 7-2). If you later decide to lengthen the clip you stabilized (by more than a second), you'll need to do more analyzing. The once-checked checkbox in the Inspector will require rechecking. Fortunately, iMovie analyzes only the new part you added that wasn't already analyzed. Then go knit a sweater while you wait for your Mac to analyze your footage. Be prepared for a wait when you decide to analyze a clip. Depending on the speed of your computer, it can take between five and twelve minutes (or longer for older Macs) for every minute of footage stabilized. If you have a lot to analyze, let the Mac do its job overnight while you get some beauty sleep. A stabilized clip in your project displays a checkmark in the Stabilization box, plus the Maximum Zoom slider. Turn Stabilization on and off all you like; iMovie never has to analyze a clip but once.