Accelerating video transcoding using the GPU is all the rage these days, and AMD is working hard to stay ahead of the curve. Earlier today, the company quietly released a Catalyst driver hotfix that includes a brand-new ATI Stream transcoding runtime.
The runtime promises quicker video transcoding with lower CPU usage. AMD Technical Manager Ab Nacef told us two new features in particular make that possible: fast UVD decoding and GPU-based resolution scaling. The Universal Video Decoder has been around in Radeon graphics cards for a while, and it normally offloads high-definition video decoding for real-time playback. For the new runtime, AMD "unlocked" the video processor to enable non-real-time decoding. As for resolution scaling, Nacef says doing that on the GPU saves a lot of memory bandwidth.
Here's a diagram of the new ATI Stream transcoding pipeline. AMD makes no secret of the fact that the GPU doesn't do all the work—the CPU still takes care of tasks like entropy estimation:
The new runtime should speed up AMD's own Avivo Video Transcoder, but that's only part of the story. Nacef explained, "We've been working . . . to enhance the transcoding engine that the application uses. And also it was actually a good exercise for us to help our [software vendor] partners to get up to speed very quickly and integrate the transcoding engine in their applications. It became sort of a reference design that matured over time."
Case in point: CyberLink's MediaShow Espresso. The software already works with the previous ATI Stream transcoding runtime, and the next update will bring support for the new version. AMD expected the Espresso update to be out today, but as far as we can tell, it's not on the CyberLink website just yet.
Other third-party apps should soon take advantage of the new-and-improved runtime. AMD is "working closely" with CyberLink to bring PowerDirector 7 up to speed (like Espresso, the current version already supports the previous runtime). ArcSoft also plans to add ATI Stream support to its SimHD plug-in next month. Nacef wasn't willing to name names, but he suggested even more firms will come out with Stream-accelerated video apps over the next couple of months.