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Message: <blockquote data-quote="imhotep" data-source="post: 25560775" data-attributes="member: 562115">True... I didn't want to mention as the answer was going to be long.  HEVC can deliver high-quality 4k video that is up to 75% smaller and promised the way forward to 8k HDR.Older H.264 breaks an image down into squares of pixels called “macroblocks,” HEVC breaks down the images into “Coding Tree Units” (CTUs) that can be up to 64×64 pixels.Each macroblock within H.264 can have only interframe (pixels borrowed from the adjacent frame of video) or intraframe (pixels borrowed from the same frame) prediction, but not both.In HEVC, CTUs actually use a combination of inter- and intraframe compression. Also in HEVC the macroblock doesn't need to be square. Can be of any shape. This allows much more flexibility in the compression process.In H.264 intraframe compression, there are only eight ways for each block to borrow nearby pixels.  But HEVC can use up to 35 different methods to borrow nearby pixels.Also considerable improvement in the reduction of artefacts was achieved by using new kinds of filtering - sample adaptive offset (SAO) and adaptive loop filtering (ALF). But the problem with HEVC failing to really pick up is the patent issues.  H.264 which has 1 patent pool, but HEVC (H.265) has 3 patent pools with different pricing structures and terms & conditions. This is the reason why many content providers stuck with H.264.This started a format warfare.... The outcome was the release of VP9 and AV1.VP9 -  In 2010 Google acquired a video compression company that owned VP8, a comparable alternative to H.264. YouTube then open-sourced VP8 to the public without any royalties (No licencse fees). Thus in 2015 they adopted the advanced version VP9 comparable to HEVC.AV1 - again in 2015, the Alliance for Open media was launched by many including Google, Microsoft, Mozilla and Cisco to create an open and royalty free codec called AV1. Based on Google’s open ‘VP10’ codec with technology from Cisco ‘Thor’ and Mozilla’s ‘Daala’ codecs they created a free alternative for H.265.  AV1 is able to do a better compression - about 30% more than HEVC.Many browsers now have support for AV1.Also I should briefly mention about VVC.  This is the next-generation (after HEVC) standards-based codec developed jointly by MPEG and the ITU. The quality target is 30% bitrate reduction over HEVC at the same perpetual quality.The future will be determined mainly by the patent issues..... <img src="/styles/default/xenforo/smilies/default/sad.gif"  class="smilie" loading="lazy" alt=":(" title="Sad    :(" data-shortname=":(" /></blockquote>

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