Move around one paragraph, add headings for greater clarity.
[libav.git] / LICENSE
1 FFmpeg:
2 -------
4 Most files in FFmpeg are under the GNU Lesser General Public License version 2.1
5 or later (LGPL v2.1+). Read the file COPYING.LGPLv2.1 for details. Some other
6 files have MIT/X11/BSD-style licenses. In combination the LGPL v2.1+ applies to
7 FFmpeg.
9 Some optional parts of FFmpeg are licensed under the GNU General Public License
10 version 2 or later (GPL v2+). See the file COPYING.GPLv2 for details. None of
11 these parts are used by default, you have to explicitly pass --enable-gpl to
12 configure to activate them. In this case, FFmpeg's license changes to GPL v2+.
14 Specifically, the GPL parts of FFmpeg are
16 - libpostproc
17 - some x86 optimizations in libswscale
18 - optional x86 optimizations in the files
19 libavcodec/x86/h264_deblock_sse2.asm
20 libavcodec/x86/h264_idct_sse2.asm
21 libavcodec/x86/idct_mmx.c
22 - the X11 grabber in libavdevice/x11grab.c
24 There are a handful of files under other licensing terms, namely:
26 * The files libavcodec/jfdctfst.c, libavcodec/jfdctint.c, libavcodec/jrevdct.c
27 are taken from libjpeg, see the top of the files for licensing details.
30 external libraries:
31 -------------------
33 Some external libraries, e.g. libx264, are under GPL and can be used in
34 conjunction with FFmpeg. They require --enable-gpl to be passed to configure
35 as well.
37 The nonfree external libraries libamrnb, libamrwb and libfaac can be hooked up
38 in FFmpeg. You need to pass --enable-nonfree to configure to enable them. Employ
39 this option with care as FFmpeg then becomes nonfree and unredistributable.
40 Note that libfaac claims to be LGPL, but is not.