ATI, the graphics division of AMD, has been working to spread its Stream GPGPU technology, which helps speed up applications by exploiting the parallel nature of its GPU products. Since ATI is a part of AMD, Stream has been designed to work with the CPU, instead of exclusively offloading all work onto the GPU. Signal processing, financial analysis, and protein modeling are just some of the fields that Stream can help.
Video transcoding is one of the most CPU intensive tasks, especially when converting high definition video. ATI has been working on this problem for a while, and has released its ATI Video Converter which can use Stream technology. UVD2 Fast Decode and GPU Scaling will be available for the entire Radeon HD 4000 series of graphics cards. GPU encoding in parallel stages will not be available in 45xx and 43xx cards due to bandwidth limitations, but all other 4000 series cards support it as well.
ATI is partnering with Independent Software Vendors (ISVs) to use Stream's transcoding framework. One of the first out is CyberLink, which is leveraging ATI's Unified Video Decoder (UVD) in its MediaShow Espresso video converter application. This allows it to quickly convert digital video files for use on portable devices like Apple's iPhone and Sony PSP. CyberLink has also optimized its PowerDirector 7 video editing software to take advantage of ATI Stream.
Tests conducted by ATI showed a reduction in transcoding time of at least 50% in most applications. For example, a 94 second 1920x1080 video encoded at 24 frames per second using H.264 took 131 seconds to transcode to a format suitable for the iPhone using just the CPU. It took just 46 seconds using a mid-range Radeon HD 4670 video card, reducing the time needed by almost 65%. Results would be even more dramatic using a higher end Radeon 4870 or Radeon 4890 GPU. Addition GPUs through CrossFire would provide even greater performance improvements.
Support is currently supplied by a hotfix to Catalyst 9.5, version 8.612.3 RC2 dated May 25. Full support will be included in Catalyst 9.6, which will be released in mid-June.
quote: So if they're using an old version of x264 to compare to, then they could be off as much as 15-20% on a Core 2 processor.
quote: For example, a 94 second 1920x1080 video encoded at 24 frames per second using H.264 took 131 seconds to transcode to a format suitable for the iPhone using just the CPU. So one would think they are using the same encoder
quote: It took just 46 seconds using a mid-range Radeon HD 4670 video card
quote: Addition GPUs through CrossFire would provide even greater performance improvements.