Add note about nonfree license of libfaac.
[libav.git] / LICENSE
1 Most files in FFmpeg are under the GNU Lesser General Public License version 2.1
2 or later (LGPL v2.1+). Read the file COPYING.LGPL for details. Some other files
3 have a MIT/X11/BSD-style license. In combination the LGPL v2.1+ applies to
4 FFmpeg.
6 Some optional parts of FFmpeg are licensed under the GNU General Public License
7 version 2 or later (GPL v2+). See the file COPYING.GPL for details. None of
8 these parts are used by default, you have to explicitly pass --enable-gpl to
9 configure to activate them. In this case, FFmpeg's license changes to GPL v2+.
11 Specifically, the GPL parts of FFmpeg are
13 - libpostproc
14 - some x86 optimizations in libswscale
15 - optional x86 optimizations in the files
16 libavcodec/x86/h264_deblock_sse2.asm
17 libavcodec/x86/h264_idct_sse2.asm
18 libavcodec/x86/idct_mmx.c
19 - the AC-3 decoder in libavcodec/ac3dec.c
20 - the X11 grabber in libavdevice/x11grab.c
22 Some external libraries, e.g. libx264, are under GPL and can be used in
23 conjunction with FFmpeg. They require --enable-gpl to be passed to configure
24 as well.
26 The nonfree external libraries libamrnb, libamrwb and libfaac can be hooked up
27 in FFmpeg. You need to pass --enable-nonfree to configure to enable them. Employ
28 this option with care as FFmpeg then becomes nonfree and unredistributable.
29 Note that libfaac claims to be LGPL, but is not.
31 There are a handful of files under other licensing terms, namely:
33 * The files libavcodec/jfdctfst.c, libavcodec/jfdctint.c, libavcodec/jrevdct.c
34 are taken from libjpeg, see the top of the files for licensing details.