Finally, Intel G45 VA-API Support Is Available

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y the h264 branch is just slowning down the whole machine. the video plays in a slideshow

unfortunately, that's the status - Intel are lying to us (G4x owners) for several years that they will provide Linux driver with H.264 acceleration then they submitted some initial code for that on May 16, 2011 and afterwards no any further updates or as of now H.264 acceleration with Intel G4x in Linux is not existing in practice.

however, it's interesting that according to Intel there are no such problems and it should work:

http://intellinuxgraphics.org/h264.html