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Changes between Version 54 and Version 55 of Encodings

11/05/16 05:21:20 (6 years ago)
Antoine Martin



  • Encodings

    v54 v55  
    2929{{{#!div class="box"
    3030== Choosing an Encoding ==
    31 The defaults should be good enough in most cases and will adapt to changing bandwidth conditions.
     31The default mode is automatic and should be the best option in most cases: it will adapt to changes in both bandwidth conditions and content.
    3232But if you have specific needs, the best thing to do is to try them all and choose the one that provides the best results.
    3535* if you have the required hardware, use [/wiki/Encodings/nvenc NVENC]
    3636* on LANs with 100Mbps or higher: {{{rgb}}} + zlib/lz4 should give you the best latency possible (whilst consuming quite a lot of bandwidth in the process..)
    37 * to save a little bit of bandwidth at the expense of framerate and latency, use lossless encodings: {{{png}}} or {{{webp}}}
    38 * otherwise, choose {{{h264}}} and tune the speed/quality to suit your needs (see below)
    39 * {{{VP9}}} is a good alternative to {{{h264}}} (only usable with version 0.15 onwards - too slow with older versions)
     37* to save a little bit of bandwidth at the expense of framerate and latency but keep a lossless picture, try {{{png}}} or {{{webp}}}
     38* otherwise, choose {{{h264}}}, {{{vp8}}} or {{{vp9}}} and tune the speed/quality to suit your needs (see below)
    4140The other encodings are somewhat less useful:
    42 * [/wiki/Encodings/vpx vpx : VP8] is similar to {{{h264}}} but it does not support all speed and quality tuning, it also subsamples colours which leads to visual degradation.
    4341* {{{h265}}} via {{{x265}}} is far too slow to encode
    4442* {{{jpeg}}} gives lower size/quality than other lossy encodings, use this if the video encodings are not available and you need better compression than {{{png}}} or {{{webp}}} can give you
    45 * [/wiki/Encodings/webp webp] (lossy mode) is a single image subset of {{{vpx}}}, and therefore lacks [http://en.wikipedia.org/wiki/Intra-frame intra-frame] compression - but latency is decent
    5754{{{#!div class="box"
    5855== Tuning ==
    59 The best way to choose the right options is through [/wiki/Testing].
     56The best way to choose the right option is through [/wiki/Testing].
    6057Though you may find some [http://alax.info/blog/1394 good illustrations] online to give you an idea of the trade offs.
    6158(ie: [http://blog.malayter.com/2010/12/presets-versus-quality-in-x264-encoding.html fps vs noise], [http://blogs.motokado.com/yoshi/2011/06/25/comparison-of-x264-presets/ fps vs size])
    120117* #616 {{{HEVC}}} (single frame)
    121118* #454 daala - unlikely
    122 * #455 and #464: vp9 and libvpx improvements