HD Video Playback and Encoding
Processors with the Bobcat microarchitecture do not have enough computing resources to decode high-definition video but they can get help from the integrated graphics core which is equipped with the UVD3 video engine. It means you can watch HD video in MPEG-2, H.264 and VC-1 formats on the Brazos platform without any problem as the graphics core offloads the CPU when performing such tasks. There is only a problem with 3D video. The Zacate’s graphics core cannot decode MVC, therefore it is impossible to play 3D video on Brazos-based nettops.
When it comes to playing conventional video, our tests did not reveal any problems with HD video playback in any of the popular formats. The diagrams below show the CPU load level when playing different video clips at 1080p resolution. We used Media Player Classic Home Cinema. The test clips had the following parameters: H.264, firstname.lastname@example.org fps, 23.7 Mbps and VC-1, email@example.com fps, 26.9 Mbps.
The CPU load on the Brazos platform is no higher than 30% and we couldn’t see any flaws in the playback quality. Thus, AMD’s new platform is a perfect choice for small and energy-efficient media centers and HTPCs. It is similar to the ION platform which has already found its place in such systems.
By the way, you should not think that the ION is better at decoding video because the CPU load is lower for that platform. The fact is that the dual-core Atom with Hyper-Threading technology is identified by the operating system as a quad-core processor, so the CPU load results reported in this test are lower than the real load on the CPU cores.
Besides checking out the capabilities of the Brazos platform in terms of playing MPEG-2, H.264 and VC-1 videos, we will check it out et reproducing video streamed over the Internet. Fortunately, Adobe Flash Player 10.2 is familiar with the Radeon HD 6310 core and can use its UVD3 engine to get some hardware acceleration. It means that Flash-based video players are perfectly compatible and work at low CPU load on the AMD Brazos platform. The next diagram shows the CPU load numbers when playing a 1080p video from YouTube.com.
The exact numbers are very similar to those we got when playing ordinary video clips. Thus, the Brazos platform is going to have no problems with online video services.
The UVD3 can be used for other purposes besides video playback. Particularly, it can be employed by various video transcoding tools that take some video clip, decode it and encode into a new format. The AMD Brazos platform is already supported by the popular commercial utilities Arcsoft Media Converter and CyberLink Media Espresso, so we are going to see how fast our systems are at such a job, especially as both applications can also utilize the Nvidia CUDA technology on the ION platforms. We measured the time it took to transcode a small H.264 1080p video clip into an iPhone 4 friendly format (H.264, 1280x720, 4 Mbps).
Funnily enough, we’ve got completely different results in Arcsoft Media Converter and CyberLink Media Espresso. The CyberLink application obviously prefers the ION platform whereas the Arcsoft utility runs faster on the AMD Brazos. This can be explained by how these`tools employ the APU resources offered by AMD. CyberLink Media Espresso decodes video using the UVD3 engine and then encodes it using the ordinary x86 computing cores. As opposed to that, Arcsoft Media Converter makes use of the Stream/APP technology and compresses the video clip using the graphics core’s stream processors. The second approach is more effective and the transcoding process takes less time on the AMD Brazos than on the ION platform.
Still, we must confess that, for all the optimizations implemented in the vidao transcoding tools, the ION and the Brazos are both rather slow at converting video clips. You must be prepared that converting an HD movie into a mobile-friendly format is going to take a lot of time, sometimes much more time than the length of the movie itself.