Pete O’Connell sells a very reasonably priced DVD through Creative COW that is by far the best resource that I’ve seen for learning basic rotoscoping. Seriously. And I say that as one of his competitors. 😉
There are links to tutorials and such for rotoscoping on this page.
Don’t worry that the page is for After Effects CS5. The basics of rotoscoping haven’t changed.
The big simple thing that I would say right away is that you should avoid the most common beginner mistake: Don’t draw masks directly on the layer that contains the video that you’re trying to separate. Instead, draw masks on a white solid layer (or more than one) and use the result as a track matte. This allows you to do much, much less keyframing of the mask.
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Todd Kopriva, Adobe Systems Incorporated
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