Linux API harnesses GeForce GPU's HD video capabilities

Nvidia plans to make hardware assisted video decoding available under Linux. Practically all of the recent graphics cards and mainboard chipsets with integrated graphics offer the functionality for decoding the video codecs used with Blu-ray discs and so Nvidia also plans to make this functionality available under Linux. The Nvidia developers have released first details about the specially developed Video Decode and Presentation API for Unix (VDPAU) on the X.org developers' mailing list and made comprehensive documentation for the programming interface available on the internet.

The API allows video encoded in MPEG-1, MPEG-2, H.264 or VC-1 format to be decoded on the majority of recent GPUs and mGPUs (Motherboard GPUs) that incorporate one of the various PureVideo HD units. The GeForce hardware is also able to handle post processing tasks like deinterlacing, IVTC (Inverse Telecine) and noise reduction. The setup can reportedly already be tested using beta versions of Nvidia's proprietary graphics drivers, combined with patches the VDPAU developers have released for libavcodec, libavutil, ffmpeg and mplayer. Nvidia plans to provide the patches to the developers of the those widely integrated open source packages for integration.

However, the Nvidia developers point out that VDPAU does not handle "content protection", which is not entirely inconsequential for the playback of Blu-ray discs under Linux. Playing back protected DVDs is already challenging for Linux users; legal Linux DVD playback software is quite rare, though available from some retailers, but the developers of these legal players often struggle to keep up with the new kernel, X.org and hardware developments, which complicates the legal DVD playback under Linux even further.

Nvidia has invited other hardware vendors to contribute to the development of VDPAU; the release message says the VDPAU API was designed to allow a vendor backend to be selected at run time. However, Nvidia is actually the last of the three market dominating GPU manufacturers to tackle HD playback under Linux. AMD's latest proprietary driver versions are believed to have offered some HD video playback functionality for weeks, although the vendor hasn't released any patches for open source applications. While Intel has so far not come up with a finished product, its developers have been working on making the HD functionality of recent Intel chipsets available under Linux for several months; they have closely co-operated with the open source community around X.org to create a successor for the now obsolete XvMC interface which did not offer HD video functionality.

(djwm)