Intel Sandy Bridge VA-API Video Acceleration Performance

VA-API for Intel Sandy Bridge certainly works. Besides having a lower CPU usage compared to using the common X-Video method, there were not any video playback problems when running at least the "Big Buck Bunny" test with no artifacts or other playback issues that is sometimes encountered for AMD's XvBA or when VDPAU was first introduced. Comparing the Core i5 2500K with VA-API to a GeForce 9500GT with VDPAU on the binary driver, the CPU usage was slightly lower with the Intel solution, however, with the modern CPU, the difference is not a big deal. You can easily multi-task while watching 1080p videos without the quad-core CPU breaking a sweat.

Aside from CPU usage being an important factor for many consumers, the Intel solution is fully open-source while VDPAU usage for NVIDIA requires their binary driver as no support aside from X-Video acceleration is fully implemented in the Nouveau driver (there's only been some work for XvMC as a state tracker for Nouveau Gallium3D, but XvMC still doesn't compare to VDPAU or VA-API). The Gallium3D XvMC solution uses shaders rather than the PureVideo HD engine or AMD's UVD engine on the Radeon side. Power consumption is also important for many HTPC users where their computers run 24x7, in which case the integrated graphics have the advantage.

Another important factor when deciding between different Linux graphics cards / drivers is what video API(s) are supported by the multimedia applications you wish to utilize. Most Linux video programs now support both the Video Decode and Presentation API for Unix along with the Video Acceleration API, but for those that are VA-API-only, you can still use VDPAU. Splitted Desktop Systems (the same European firm that developed the VA-API to AMD XvBA library) has developed a VA-API to VDPAU library too. Therefore, with VDPAU, applications that support it directly can do so while you can still use VA-API in other applications on the front-end with VDPAU still being used on the back-end.

Choosing between the different video API options can also come down to the video formats of your choice being supported by the given API and all of the possible processes being accelerated by the API. The SNB VA-API support is currently limited to H.264, MPEG-2, and VC-1. NVIDIA's driver with VDPAU supports MPEG-1, MPEG-2, MPEG-4 ASP, H.264. VC-1, DivX4, DivX5, and WMV3/WMV9 encoding videos, but some of these encoded formats are only supported on the newer generations of NVIDIA hardware.

These results can be further analyzed (and comparison tests run) using the Phoronix Test Suite and OpenBenchmarking.org with the video playback results and the single-core results. Overall, Intel's Sandy Bridge graphics under Linux are looking rather nice when they work (i.e. using the very latest code and not hitting any H67 motherboard issues) and with the latest Mesa 7.11 development code where the OpenGL performance is close to the Windows driver. It will also be interesting when the Sandy Bridge video encoding support arrives. Still lacking on the Linux side though is OpenGL 3.0 support and areas where there are patent concerns, including Blu-ray support.