====== x265 encoding ======

===== Metadata tag =====
Some players rely on metadata to identify if the contents of the file can be used (i.e.: QT)
<code bash>-tag:v hvc1</code>


===== Performance =====
FFmpeg supports following presets: ''ultrafast'', ''superfast'', ''veryfast'', ''faster'', ''fast'', ''medium'', ''slow'', ''slower'', ''veryslow'', and ''placebo''

According to:
  * [[https://brandur.org/fragments/ffmpeg-h265#section-3|The `fast` preset]]
  * [[https://write.corbpie.com/ffmpeg-preset-comparison-x265-2019-encode-speed-and-file-size/|FFmpeg preset comparison x265 2019; Encode speed and file size]]

and own fast tests:
<code>
  * veryslow: encoded 140 frames in 130.17s ( 1.08 fps), 1424.91 kb/s, Avg QP:27.02
  * slower:   encoded 140 frames in  66.19s ( 2.12 fps), 1412.11 kb/s, Avg QP:26.91
  * slow:     encoded 140 frames in  20.36s ( 6.88 fps), 1448.34 kb/s, Avg QP:26.61
  * medium:   encoded 140 frames in   9.44s (14.83 fps), 1260.54 kb/s, Avg QP:26.68
  * fast:     encoded 140 frames in   6.13s (22.82 fps), 1244.63 kb/s, Avg QP:26.71
  * faster:   encoded 140 frames in   5.02s (27.87 fps), 1221.05 kb/s, Avg QP:26.76
</code>


The default ''medium'' is enough (or even ''fast'').


===== Ryzen 7 =====

Preset: veryslow
Ryzen 7 8c/16t

^  threads        ^  time             ^
|  auto (16)      | 103.05s (1.83fps) |
|  12             | 103.76s (1.82fps) |
|  20             | 103.93s (1.82fps) |
|  8              | 107.09s (1.76fps) |
|  6              | 136.09s (1.39fpc) |