One theory is that NVIDIA's entropy encode block could be the limiting factor here. However ask for more aggressive compression ratios for lower resolution/bitrate targets, and the Intel solution quickly distances itself from NVIDIA. When asked to preserve a good amount of data, both NVENC and Quick Sync perform similarly in our 1080p/13Mbps test. Unfortunately NVENC performance does not scale like Quick Sync. I targeted 1080p, 720p and 480p at decreasing average bitrates to illustrate the relationship between compression demands and performance: In the tests below I took the same source and varied the output quality with some custom profiles. However even using Handbrake as a reference, Quick Sync transcodes over 2x faster. You will notice that the Handbrake x86/x264 path is definitely faster than Cyberlink's software path, by over 50% to be exact. We took the profile and performed the same transcode, the result is listed above as the Core i7 3770K (Handbrake). I asked our resident video expert, Ganesh, to clone Media Espresso's settings in a Handbrake profile. One thing I wanted to make sure of was that Media Espresso wasn't somehow holding x86 performance back to make the GPU accelerated transcodes seem much better than they actually are. Just as we saw with Sandy Bridge, Quick Sync continues to be an incredible way to get video content onto devices other than your PC. The chart below is average frame rate over the entire encode process. The performance story is unfortunately not much different from last year either. While NVENC delivers acceptable image quality, AMD does not. The washed out images we saw last year, particularly in dark scenes prior to a significant change in brightness are back again. Unfortunately AMD's solution hasn't improved. For getting videos onto your phone, tablet or game console I'd say the output of either of these options, NVENC or Quick Sync, is good enough. ![]() The good news is that NVENC doesn't pose any of the horrible image quality issues that NVIDIA's CUDA transcoding path gave us last year. I'm not sure I'd call it bad, but I need to do some more testing before I know whether or not it's a good thing. It seems that Quick Sync, at least in this case, is sharpening/adding more noise beyond what you'd normally expect. However, if you compare the NVENC output to what we got from the software/x86 path you'll see that the two are quite similar. Once again, Quick Sync's transcoding abilities are limited to applications like Media Espresso or ArcSoft's Media Converter-there's still no support in open source applications like Handbrake.Ĭompared to the output from Quick Sync, NVENC appears to produce a softer image. Cyberlink Media Espresso 6.5 will take advantage of the 680's NVENC engine which is why we standardized on it here for these tests. While AMD has yet to enable VCE in any publicly available software, NVIDIA's hardware encoder built into Kepler is alive and well. For most phone/tablet use I'd say the faster performing option is ideal. Both options produced a good quality transcode, picking one over the other really depends on how much time (and space) you have as well as the screen size of the device you'll be watching it on. The resulting file size for the entire movie increased from 3.78GB to 5.71GB. In the case of our Harry Potter transcode, selecting the Better Quality option increased average bitrate from to 3.86Mbps to 5.83Mbps. To test image quality and performance, I took the last Harry Potter Blu-ray, stripped it of its DRM and used Media Espresso to make it playable on an iPad 2 (1024 x 768 preset). The option is exposed in Media Espresso and ultimately corresponds to an increase in average bitrate. Intel's latest drivers now allow for a selectable tradeoff between image quality and performance when transcoding using Quick Sync. In fact, you get a bit more flexibility than you had a year ago. ![]() ![]() Intel put to rest any concerns about image quality when Quick Sync launched, and thankfully the situation hasn't changed today with Ivy Bridge. The combination of the two resulted in some pretty incredible performance gains not only over traditional software based transcoding, but also over the fastest GPU based solutions as well. The power of Quick Sync was how it leveraged fixed function decode (and some encode) hardware with the on-die GPU's EU array. Plus it doesn't hurt that video transcoding is an extremely popular activity to do with one's PC these days. At the time, video transcode seemed to be the most likely candidate for significant GPU acceleration so the move made sense. As you may recall, Sandy Bridge's secret weapon was an on-die hardware video transcode engine (Quick Sync), designed to keep Intel's CPUs competitive when faced with the onslaught of GPU computing applications. Intel obviously focused on increasing GPU performance with Ivy Bridge, but a side effect of that increased GPU performance is more compute available for Quick Sync.
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