Changes between Version 2 and Version 3 of Encode/H.265


Ignore:
Timestamp:
Oct 18, 2014, 9:21:19 PM (5 years ago)
Author:
slhck
Comment:

give a bit more context

Legend:

Unmodified
Added
Removed
Modified
  • Encode/H.265

    v2 v3  
    11= FFmpeg and H.265 Encoding Guide =
    22
    3 [[PageOutline(2, Contents)]]
     3The goal of this guide is to inform new users how to create a high-quality H.265 video using the encoder x265. '''Note:''' libx265 is under heavy development. The API may change.
    44
    5 The goal of this guide is to inform new users how to create a high-quality H.265 video using the encoder x265.
     5H.265 (also known as HEVC) offers 50-75% compression efficiency compared to an H.264 video, while retaining the same quality. Similar to x264, the x265 encoder has multiple rate control algorithms, including:
    66
    7 == Passing options to libx265 ==
     7* 1-pass constant bitrate
     8* 2-pass constant bitrate
     9* Constant Rate Factor (CRF)
    810
    9 The encoding is done by libx265, which is under heavy development. As of now, options such as CRF or psy-rd has to be passed using the `-x265-params` options.
     11== Constant Rate Factor (CRF) ==
    1012
    11 === Simple example (crf) ===
     13In this guide we are going with CRF encoding. Use this mode if you want to retain a good quality and don't care about bitrate or filesize. It works exactly the same as in x264, so read the [[H.264]] guide for more info.
     14
     15In this example, we will use the default CRF of 28, the "medium" profile, and AAC audio at 128 kBit/s. The CRF of 28 should visually correspond to libx264 video at CRF 23, but result in about half the file size. The profile determines how fast the encoding process will be – at the expense of compression efficiency.
    1216
    1317{{{
    14 ffmpeg -i input -c:v libx265 -preset medium -x265-params crf=28 -c:a copy output
     18ffmpeg -i input -c:v libx265 -preset medium -x265-params crf=28 -c:a aac -strict experimental -b:a 128k output.mp4
    1519}}}
    1620
    17 The CRF of 28 corresponds to the default value and should be visually equivalent to libx264 video at CRF 23.
     21Generally, options are passed to x265 with the `-x265-params` argument.
     22
     23== Further Info ==
     24
     25[http://x265.readthedocs.org/en/default/ x265 API documentation]