DVD Studio Pro 3: In the Studio

Alpha Transitions

So, now that you've put all that energy into creating those specific transitions, they are good for exactly one project. Sigh. Wouldn't it be great if you could spend your time making a generic transition and then be able to reuse it over and over? Well, with DVDSP 3, you can. You can build custom transitions and then add them to your Application Support library and they'll appear in the pop-up lists, along with the built-in transitions.

But how, you ask, can one make a "generic" transition? That's why you see "Alpha" in the heading for this section. DVDSP can use the alpha channel of a movie to decide what parts of a transition should show which assets. Actually, DVDSP allows fairly complex transitions, so it takes more than just one movie with an alpha channel, but we're getting ahead of ourselves.

Before we get any further, we need to set down a few ground rules. Well, not so much "ground rules" as vocabulary terms, but they are important vocabulary terms! First off, when talking about custom transitions, the word asset gets a bit overused. So far we've talked about assets in terms of images, video clips, and audio clips that you use to build a DVD. Anything you can put in the Asset view is, well, an asset. However, Apple also uses asset in transitions to refer to any external video involved in a transition. Because the names of things are important in building custom transitions, we're going to rely on that second definition of asset. So:

• A will refer to the ...