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Derived Media Handler Components Update

Q What is a practical limit on data transfer rates for the base media handler on Power Macintoshes with PCI and QuickTime 2.5? Also, is the MPEG media handler derived from the base one?

A The practical limit on data transfer rates depends on your drive and SCSI bus. With a high performance hard drive connected to a PCI SCSI card, I've seen video data transfer rates up to 15 MB/sec. All media handlers, except for Sound and Video, are derived from the base media handler. This includes MPEG, text, tween, 3d, timecode, music, and sprites.

You should also be aware of the fact that as of QuickTime 2.0, the statement in Inside Macintosh regarding performance limitations of Derived Media Handlers is no longer accurate, because you now have access to everything we use inside QuickTime's sound and video media handlers. Inside Macintosh was referring to the fact that the Data Handler API wasn't yet publicly available for versions of QuickTime earlier than 2.0.

[Aug 21 1996]


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