I find this pre-release of CoreVideo.framework for Tiger OS X 10.4
performs a lot better than their eventual retail versions of
CoreVideo. Follow the instructions included in the download.

note: Using any QuickTime 7.1.6 or higher update, or, using any
delta/combo 10.4.9 10.4.10 10.4.11 updaters - will likely overwrite
this, so you'll have to install this after doing those things
beforehand.

Compatibility
Architecture: PPC x86 (Intel:Mac)

OS X Tiger only.
Tested on OSX 10.4.8 with QuickTime 7.1.5
and on OSX 10.4.11 with QuickTime 7.1.6SU