x265 is a free software library and application for encoding video streams into the H.265/MPEG-H HEVC compression format, and is released under the terms of the GNU GPL.
The latest x265 source code can always be found by anonymous git repository:
# git clone https://bitbucket.org/multicoreware/x265_git.git
You can browse the source on-line.
For support information and to ask questions, you have the following possibilities:
A mailing list (x265-devel), and IRC (#x265@freenode and #x265dev@freenode).
Please report any bugs to the mailing list. If it is a crash, then compile x265 with `./configure --enable-debug`
and follow the ffmpeg bugreporting guidelines.
In addition to being free to use under the GNU GPL, x265 is also available under a commercial license from MulticoreWare Inc.
If you use x265 in another project, let us know!