open h.265 video codec实现方法：libde265

open h.265 video codec implementation:

libde265

libde265 is an open source implementation of the h.265 video codec. It is written from scratch and has a plain C API to enable a simple integration into other software.
libde265 supports WPP and tile-based multithreading and includes SSE optimizations. The decoder includes all features of the Main profile and correctly decodes almost all conformance streams (see [wiki page]).
A list of supported features are available in the wiki.
For latest news check our website at http://www.libde265.org
The library comes with two example programs:

• dec265, a simple player for raw h.265 bitstreams. It serves nicely as an example program how to use libde265.
  
• sherlock265, a Qt-based video player with the additional capability to overlay some graphical representations of the h.265 bitstream (like CU-trees, intra-prediction modes).
  

Example bitstreams can be found, e.g., at this site: ftp://ftp.kw.bbc.co.uk/hevc/hm-10.1-anchors/bitstreams/ra_main/
Approximate performance for WPP, non-tiles streams (measured using the timehevc tool from the GStreamer plugin). The tool plays a Matroska movie to the GStreamer fakesink and measures the average framerate.

Resolution	avg. fps	CPU usage
720p	284 fps	39 %
1080p	150 fps	45 %
4K	36 fps	56 %

Environment:

• Intel(R) Core(TM) i7-2700K CPU @ 3.50GHz (4 physical CPU cores)
• Ubuntu 12.04, 64bit
• GStreamer 0.10.36

Building

If you got libde265 from the git repository, you will first need to run the included autogen.sh script to generate the configure script.
libde265 has no dependencies on other libraries, but both optional example programs have dependencies on:

• SDL (optional for dec265's YUV overlay output),
  
• Qt (required for sherlock265),
  
• libswscale (required for sherlock265 if libvideogfx is not available).
  
• libvideogfx (required for sherlock265 if libswscale is not available, optional for dec265).
  

Libvideogfx can be obtained from http://www.dirk-farin.net/software/libvideogfx/index.html or http://github.com/farindk/libvideogfx
You can disable building of the example programs by running ./configure with

  --disable-dec265        Do not build the dec265 decoder program.
  --disable-sherlock265   Do not build the sherlock265 visual inspection program.

Additional logging information can be turned on and off using these ./configure flags:

  --enable-log-error      turn on logging at error level (default=yes)
  --enable-log-info       turn on logging at info level (default=no)
  --enable-log-trace      turn on logging at trace level (default=no)

Build using cmake

cmake scripts to build libde265 and the sample scripts dec265 and enc265 are included and can be compiled using these commands:

mkdir build
cd build
cmake ..
make

See the cmake documentation for further information on using cmake on other platforms.

Prebuilt binaries

Binary packages can be obtained from this launchpad site.

Software using libde265

Libde265 has been integrated into these applications:

• gstreamer plugin, source, binary packages.
  
• VLC plugin source, binary packages.
  
• Windows DirectShow filters, https://github.com/strukturag/LAVFilters/releases
  
• ffmpeg fork, https://github.com/farindk/ffmpeg
  
• ffmpeg decoder source
  
• libde265.js JavaScript decoder source, demo
  
  from  https://github.com/strukturag/libde265