HD Video Decoding on GPUs with VLC 1.1.0by Ganesh T S on June 25, 2010 4:35 AM EST
VLC has taken the important first step towards enabling GPU acceleration for various codecs commonly used in high definition videos. However, they have been crippled by their application structure, resulting in the fact that they are unable to provide the same amount of acceleration as other methods like DXVA using MPC-HC / Windows Media Player. While the untested Arrandale provided around 5% CPU usage improvement for VC-1 decode, PureVideo VP2 had speed-ups of around 60% for H264 and 20% for VC1. PureVideo VP4 turned out to be the best of the lot when GPU acceleration is enabled. CPU usage was lesser by a factor more than 65% for H264 and 36% for VC1.
Are these numbers good enough for the occasional HD video watcher? I would say, yes, as soon as the GPU vendors fix their drivers for the remaining minor issues. But, for the HD enthusiast with terabytes of Blu-Ray backups, I would still advise sticking with MPC-HC / Windows Media Player / favourite software Blu-Ray player.
GPU vendors should get their act together and work with the VLC developers to ensure smooth interaction between their drivers and VLC. This has already been done between the MPC-HC / mplayer - VDPAU developers and Nvidia / Intel. VLC, being much more popular, should not have much trouble in this respect (as indicated by how long it took CatalystMaker to tweet regarding Catalyst support for VLC). The vendors and developers should also look into ways to further the performance gains that have been realized with this first release. It will probably not be long before all GPU vendors support this type of acceleration at the basic level. That would be time for the VLC developers to enable GPU acceleration by default, and take away the experimental tag associated with it.
On other HD media aspects related to VLC, it is heartening to note support for WMAPro audio in the past few releases. Would it be wishful thinking to see audio passthrough / HD audio bitstreaming implemented internally in VLC? Hopefully not! Anandtech takes this opportunity to thank the VLC developers for creating and supporting one of the best open source softwares of all time.
Note: Don't forget to check out the update section on the next page, where I have tried to address some comments from readers (both here, and also in private communication)