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Intel Quick Sync Video is the name given to Intel's hardware video encoding and decoding technology integrated into some of its CPUs. The name "Quick Sync" refers to the use case of quickly transcoding ("syncing") a video from, for example, a DVD or Blu-ray Disc to a format appropriate to, for example, a smartphone. Quick Sync was introduced with the Sandy Bridge CPU microarchitecture on 9 January 2011. Quick Sync has been praised for its speed.〔(【引用サイトリンク】title=The Sandy Bridge Review: Intel Core i7-2600K, i5-2500K and Core i3-2100 Tested )〕 The eighth annual MPEG-4 AVC/H.264 video codecs comparison showed that Quick Sync is comparable to x264 superfast preset in terms of speed, compression ratio and quality (SSIM);〔(【引用サイトリンク】title=Eighth MPEG-4 AVC/H.264 Video Codecs Comparison. )〕 tests were performed on an Intel Core i7 3770 (Ivy Bridge) processor. A benchmark from ''Tom's Hardware'' showed that Quick Sync could convert a 449 MB, four-minute 1080p file to 1024×768 in 22 seconds. The same encoding using only software took 172 seconds but it is not clear what software encoder was used and how it was configured. The same encoding took 83 or 86 seconds GPU-assisted, using an Nvidia GeForce GTX 570 and an AMD Radeon HD 6870, respectively, both of which are contemporary high-end GPUs.〔(【引用サイトリンク】title=Intel's Second-Gen Core CPUs: The Sandy Bridge Review - Quick Sync Vs. APP Vs. CUDA )〕 Unlike video encoding on a general-purpose GPU, Quick Sync is a dedicated hardware core on the processor die. This allows for faster and more power efficient video processing.〔(【引用サイトリンク】title=Intel's Second-Gen Core CPUs: The Sandy Bridge Review - Sandy Bridge's Secret Weapon: Quick Sync )〕 Quick Sync, like other hardware accelerated video encoding technologies, gives lower quality results than with CPU only encoders. Speed is prioritized over quality.〔(【引用サイトリンク】title=H.264 encoding - CPU vs GPU: Nvidia CUDA, AMD Stream, Intel MediaSDK and x264 )〕 ==Quick Sync development== Quick Sync was first unveiled at Intel Developer Forum 2010 (13 September) but, according to Tom's Hardware, Quick Sync had been conceptualized 5 years before that.〔 The older Clarkdale microarchitecture had hardware video decoding support, but no hardware encoding support.〔 known as Intel Clear Video. ; Generation 1 (Sandy Bridge) : Quick Sync was initially built into some Sandy Bridge CPUs, but not into Sandy Bridge Pentiums or Celerons. ; Generation 2 (Ivy Bridge) : The Ivy Bridge microarchitecture included a "next generation" implementation of Quick Sync.〔(【引用サイトリンク】title=Intel's Roadmap: Ivy Bridge, Panther Point, and SSDs )〕 ; Generation 3 (Haswell) : The Haswell microarchitecture implementation was focused on quality, with speed about the same as before (for any given clip length vs. encoding length). It has seven hard-coded quality/performance levels (called "target usages"), compared to the three in previous generations. The highest-quality TU1 setting is intended to be higher quality than Ivy Bridge's version, and the highest speed TU7 setting should be faster, higher-quality, and more battery-friendly for mobile devices. : This generation of Quick Sync supports the H.264/MPEG-4 AVC, VC-1 and H.262/MPEG-2 Part 2 video standards.〔 ; Generation 4 (Broadwell) : The Broadwell microarchitecture adds VP8 hardware decoding and encoding support. Also, it has two independent bit stream decoder (BSD) rings to process video commands on GT3 GPUs; this allows one BSD ring to process decoding and the other BSD ring to process encoding at the same time. ; Generation 5 (Skylake) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Intel Quick Sync Video」の詳細全文を読む スポンサード リンク
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