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Changes between Version 5 and Version 6 of Encodings/x264


Ignore:
Timestamp:
12/11/13 10:09:25 (7 years ago)
Author:
Antoine Martin
Comment:

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  • Encodings/x264

    v5 v6  
     1{{{#!div class="box"
    12= x264 Encoder =
    23x264 is the encoding that supports the most options and tunings. It is the default encoding used when it is available because it offers the best performance and compression out of the box.
     
    45Quality/speed and minimum quality/speed can be set via the command line or via the tray menu.
    56Note that even when using the x264 encoding, some small screen updates may get sent as png or rgb24 to save time/bandwidth (not encoding a full frame).
     7}}}
    68
     9{{{#!div class="box"
    710== Links ==
    811* [http://www.avidemux.org/admWiki/doku.php?id=tutorial:h.264 H.264 encoding guide] for more information on x264 options
     
    1215* [/wiki/Encodings] - all the picture encodings available
    1316* [/wiki/CSC] - the Colourspace conversion step
     17}}}
    1418
    1519
     20{{{#!div class="box"
    1621== Profiles ==
    1722(see [http://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Profiles wikipedia h264 profiles])
     
    1924
    2025At present, we use {{{high}}} or better by default unless the client overrides it.
     26}}}
    2127
    2228
     29{{{#!div class="box"
    2330== Quality Option ==
    2431What this does should be obvious (in x264 speak, this controls the {{{rc.f_rf_constant}}} parameter), but it is more complicated than you think:
     
    2734* some builds against older versions of libav/ffmpeg only support {{{YUV420}}},
    2835 see [/browser/xpra/trunk/src/patches/x264-limited-csc.patch x264-limited-csc.patch]
     36}}}
    2937
    3038
     39{{{#!div class="box"
    3140== Speed Option ==
    3241This option, shown as "latency" via the tray menu, controls how hard the encoder is going to work at compressing the picture. Working harder means lower bandwidth, but also higher latency.
     
    3544{{{veryslow}}} and {{{placebo}}} are not particularly useful (diminishing returns: much much slower and without sufficient savings for real-time use).
    3645{{{ultrafast}}} is only available when setting the encoder speed to 100% manually (via the command line or UI) - note that this setting has side-effects which prevents other settings from behaving as they should if the option is later changed.
     46}}}