VDA
From MythTV Official Wiki
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, GeForce GT 330M, ATI HD Radeon GFX, Intel HD Graphics and others.
For the list of supported Apple hardware refer to: http://support.apple.com/kb/HT3246
For detailed description of the VDA framework: https://developer.apple.com/library/mac/#technotes/tn2267/_index.html#//apple_ref/doc/uid/DTS40009798
