3 Most files in FFmpeg are under the GNU Lesser General Public License version 2.1
4 or later (LGPL v2.1+). Read the file COPYING.LGPLv2.1 for details. Some other
5 files have MIT/X11/BSD-style licenses. In combination the LGPL v2.1+ applies to
8 Some optional parts of FFmpeg are licensed under the GNU General Public License
9 version 2 or later (GPL v2+). See the file COPYING.GPLv2 for details. None of
10 these parts are used by default, you have to explicitly pass --enable-gpl to
11 configure to activate them. In this case, FFmpeg's license changes to GPL v2+.
13 Specifically, the GPL parts of FFmpeg are
17 - optional x86 optimizations in the files
18 libavcodec/x86/idct_mmx.c
19 - libutvideo encoding/decoding wrappers in
20 libavcodec/libutvideo*.cpp
21 - the X11 grabber in libavdevice/x11grab.c
22 - the swresample test app in
23 libswresample/swresample-test.c
24 - the texi2pod.pl tool
25 - the following filters in libavfilter:
43 There are a handful of files under other licensing terms, namely:
45 * The files libavcodec/jfdctfst.c, libavcodec/jfdctint_template.c and
46 libavcodec/jrevdct.c are taken from libjpeg, see the top of the files for
47 licensing details. Specifically note that you must credit the IJG in the
48 documentation accompanying your program if you only distribute executables.
49 You must also indicate any changes including additions and deletions to
50 those three files in the documentation.
52 Should you, for whatever reason, prefer to use version 3 of the (L)GPL, then
53 the configure parameter --enable-version3 will activate this licensing option
54 for you. Read the file COPYING.LGPLv3 or, if you have enabled GPL parts,
55 COPYING.GPLv3 to learn the exact legal terms that apply in this case.
61 FFmpeg can be combined with a number of external libraries, which sometimes
62 affect the licensing of binaries resulting from the combination.
67 The libcdio, libx264, libxavs and libxvid libraries are under GPL. When
68 combining them with FFmpeg, FFmpeg needs to be licensed as GPL as well by
69 passing --enable-gpl to configure.
71 The OpenCORE and VisualOn libraries are under the Apache License 2.0. That
72 license is incompatible with the LGPL v2.1 and the GPL v2, but not with
73 version 3 of those licenses. So to combine these libraries with FFmpeg, the
74 license version needs to be upgraded by passing --enable-version3 to configure.
76 incompatible libraries
77 ----------------------
79 The Fraunhofer AAC library, FAAC and aacplus are under licenses which
80 are incompatible with the GPLv2 and v3. We do not know for certain if their
81 licenses are compatible with the LGPL.
82 If you wish to enable these libraries, pass --enable-nonfree to configure.
83 But note that if you enable any of these libraries the resulting binary will
84 be under a complex license mix that is more restrictive than the LGPL and that
85 may result in additional obligations. It is possible that these
86 restrictions cause the resulting binary to be unredistributeable.