Quote Originally Posted by g-man View Post
Are there applications of either the tested hardware set or the tested software suite (VDPAU + FFMPEG & others) to H.264 encode in any way, or is this application set limited strictly to playback optimization?
VDPAU (and DXVA on Windows) is limited to decoding. The supported GPUs contain specialized hardware that is only suitable for video decoding. This also applies to ATI's UVD.

I would imagine that a number of the GPU primitives in the chip would allow to address both worlds to some extent, but I do not know if the VDPAU wouldbe effective glue.
Using the shaders or stream processors of a GPU for general purpose computing is getting easiear and there have been some attempts to both decode and encode using them. However, current GPU encoder implementations are still less efficient than good software encoders run on modern CPUs.

This topic has been discussed more thoroughly (and many times over) at the Doom9 MPEG-4 AVC forum. This post links to some relevant threads: http://forum.doom9.org/showthread.php?p=1193278