Then a series of PNG frames were extracted from the input and output files using FFMPEG, visually aligned to ensure validity, compared using a slightly modified version of Chris Lomont’s SSIM implementation, and then averaged to provide the number presented. As mentioned before, each target scenario was run on the respective IPG using QSTranscode to produce an output file. This changed with the latest spin of Intel HD graphics, with each step fully selectable, but as this is a mostly a comparison between the 3 rd and 4 th generations they will not be included in the discussion.Īll of the tests were conducted on a 4 th generation “Haswell”(HSW) Intel Core i7-4770K with HD 4600 graphics and a 3 rd generation “Ivy Bridge” (IVB) Intel Core i7-3770K with HD 4000 graphics using QSTranscode for transcoding AVC/MPEG2/VC-1 to AVC at the source frame size and rate using the “-bench” command line argument to bypass any additional file I/O or CPU utilization caused by transcoding or writing audio streams.īefore discussing the results, let’s briefly outline the methodology used to produce them. On previous iterations, while there were technically seven steps only three were really exposed for consumption: quality (TU1), balanced (TU4), and speed (TU7). This feature is intended to enable simple access to a series of gradations without the complexity around forcing users to select a bit rate and rate control method. In addition to the traditional set of encoding “knobs-and-dials” Intel also exposes the concept of “Target Usage” (TU). Different in the 4 th generation Core release, is that Intel has refocused on prioritizing quality over speed–which is important to point out because for specific encoding settings Quick Sync is actually slower on the newest hardware than in the last generation. The feature was originally intended for converting files for mobile use, but has advanced over the iterations to provide coverage for a larger set of use cases. First, for those who do not know, Intel Quick Sync is a feature first introduced with 2 nd generation Core IPG (Sandy Bridge) which enables hardware accelerated video transcoding, or the process of changing the video stream in one file to a different format (CODEC, size, bit rate, etc.) in another. While a detailed examination of new Quick Sync features is best left to the whitepaper a brief outline will help facilitate the discussion. In the pursuit of this goal the differences in Quick Sync speed and quality between 3 rd and 4 th generation Intel Core IPG will be detailed as well as how it compares with x264 when it matters the most – archiving high-bitrate material. The detailed why and how of Quick Sync, or specifically what has changed versus the previous generation is beyond the scope of this discussion this somewhat because Intel has already published a reasonably detailed whitepaper on the topic for those with academic interest, but mostly it is because results matter more than technical diagrams. As the review developed, it became evident quite quickly that this aspect of the Intel Core i7-4770K warranted specific coverage outside of the more general platform/system/performance characteristics that are usually covered. In the recent release of 4 th generation (Haswell) Intel Core integrated processor graphics (IPG), Intel placed significant focus on changes made to Quick Sync transcoding technology included with the HD graphics portion of the chip.
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