Audio and Video Transcoding
We use Apple iTunes utility to test audio transcoding speed. It translates the contents of a CD disk into AAC format. Note that the typical peculiarity of this utility is its ability to utilize only a pair of processor cores.
Apple iTunes uses two CPU cores only, which explains the results. The dual-core Core i5 series processors with higher clock rates are in the lead.
In order to measure how fast our testing participants can transcode a video into H.264 format we used x264 HD benchmark. It works with an original MPEG-2 video recorded in 720p resolution with 4 Mbps bitrate. I have to say that the results of this test are of great practical value, because the x264 codec is also part of numerous popular transcoding utilities, such as HandBrake, MeGUI, VirtualDub, etc.
In our previous reviews AMD processors used to be good enough at transcoding video with the x264 codec. But when it comes to the top-end products, the Phenom II X6 falls behind Intel’s six-core CPUs as well as many of the quad-core Core i7 series models that support Hyper-Threading.
The performance in Adobe Premiere Pro is determined by the time it takes to render a Blu-ray project with HDV 1080p25 video into H.264 format and apply different special effects to it.
We’ve got the same standings in the Adobe Media Encoder test as when using the x264 codec. Summing up these results, we can say that the six-core Core i7 series is most appropriate for video editing. Installing a Core i7-970 or a Core i7-980X instead of an expensive quad-core model may boost the computer’s performance in such applications by 50% and more! This is quite normal as video processing algorithms can effectively run in multiple parallel threads.