iMovie 6 & iDVD: The Missing Manual

Optimizing Online Movies

This chapter covers the fundamentals of putting your iMovie on the Web, but there’s a lot more to online video. The next step is tweaking the movie files themselves to optimize them for online viewing.

When you put your movie on the Web, millions of people can see it, which is wonderful. Unfortunately, some of those people connect to the Internet using dial-up modems, some use high-speed broadband connections like cable modems and DSL, while the luckiest connect through such ultrafast pipes as T1 lines. If you had the time, hard drive space, and inclination, you could actually create different versions of your movie, one for each of these connection speeds. For instance, a cable modem owner would see a high-resolution, 320 x 240 movie playing at fifteen frames per second. His neighbor, dialing in on a 56 K modem, would see a 240 x 180 version (an alternate version) playing ten frames per second. Each person would see an appropriately sized rendition that would be as large and beautiful as that kind of Internet connection would permit.

(How does a Web page know which version of the movie to transmit? The answer lies in the QuickTime panel of System Preferences. If you click the Connection tab, you’ll see the list of different connection methods—modem, DSL/Cable, and so on. You’re supposed to choose the one that connects you to the Internet. When you click a movie on a Web page, the Web page computer actually asks your Mac what kind of connection speed you’ve ...