Via the latest 10.6.3 update for Mac OS X Snow Leopard, Apple seems to be finally allowing third party developers to access the low level H.264 decoding power of the GPUs within its Macs.
Adobe’s upcoming Flash Player 10.1 only provides hardware acceleration to Windows-based computers because Mac OS X “does not expose access to the required APIs” and Linux lacks a “developed standard API” for H.264 hardware decoding.
Apple seems to have addressed this issue now with Video Decode Acceleration Framework. Technical Note TN2267 describes the new API:
The Video Decode Acceleration framework is a C programming interface providing low-level access to the H.264 decoding capabilities of compatible GPUs such as the NVIDIA GeForce 9400M, GeForce 320M or GeForce GT 330M. It is intended for use by advanced developers who specifically need hardware accelerated decode of video frames.
The new framework should allow Adobe and other developers to provide smoother and more efficient raw H.264 decoding in their software through the GPU. Developers were previously required to use the QTKit API to gain hardware acceleration through Quicktime X which has limited format support and cannot render onto third party video players.
Update: Adobe has responded to the new API and will be offering H.264 acceleration for OS X shortly after 10.1 releases.
"We will be enabling support for hardware accelerated video decoding for Flash Player on Mac," Adobe spokesperson Matt Rozen told Ars. "Now that the required APIs are available, we are working on an additional Flash Player release to follow shortly after Flash Player 10.1 to include this functionality for the hardware configurations supported by the new APIs."