I just started an app involving video and I see other apps that seem to add contrast / brightness / zoom and various effects. I don't see any of that in the Apple documentation. My guess is that they capture frames, alter the frames and then feed them into a preview window. Is that how it's done, or am I not seeing something that's in Apple's documentation? Anyone know of a site/book that has a tutorial on working with video that actually goes beyond recording and playback?