CompuServe Messages

Quicktime is a very weird setup. It keeps video in a delta format very similar to our ANIM 5 format (in terms of concept, not actual file layout) and ties sound to it. The basic difference is that while all (as far as I know) Amiga ANIM players play each and every frame, with time synchronization only if the ANIM is playing faster than the time sync needs, the Quicktime player forces time synchronization no matter *what* speed the frames are being drawn. If it falls behind, it skips frames. The drawback of the Quicktime technique is that in order to skip frames, it has to have a full frame to work with as a base, since all the delta calculations are dependant on the previous frame. So if there are sequences where a long period of time exists between frames which are totally different (thus requiring storage of a full frame delta) and it falls behind, the video appears to freeze until the time for the next full frame is reached. Of course, you can always arrange at coding time to insert full frames every so often to reduce this problem. (With digitized movies, etc. it's not as bad, since variants in color and the like mean that most frames end up being full frame deltas. Not great for speed, but quite acceptable for Quicktime.) It ought to be a rather trivial thing for someone to hack up an ANIM player which would play at a fixed frame per second rate and if it fell behind would wait until the next full frame delta and skip directly to it. You'd need a couple of ANIMs with extra full frames inserted every half second or so in order to make it look good, but that shouldn't be too difficult. Of course, if you limit the animation to a smaller size on the screen, you ought to be able to run it displaying all frames without skipping, and still synchronize with sound. (a la CD-XL) –>Steve Bennett