4 Most files in Libav 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
9 Some optional parts of Libav 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, Libav's license changes to GPL v2+.
14 Specifically, the GPL parts of Libav are
16 - the X11 grabber in libavdevice/x11grab.c
17 - the texi2pod.pl tool
18 - the following filters in libavfilter:
25 Should you, for whatever reason, prefer to use version 3 of the (L)GPL, then
26 the configure parameter --enable-version3 will activate this licensing option
27 for you. Read the file COPYING.LGPLv3 or, if you have enabled GPL parts,
28 COPYING.GPLv3 to learn the exact legal terms that apply in this case.
30 There are a handful of files under other licensing terms, namely:
32 * The files libavcodec/jfdctfst.c, libavcodec/jfdctint_template.c and
33 libavcodec/jrevdct.c are taken from libjpeg, see the top of the files for
34 licensing details. Specifically note that you must credit the IJG in the
35 documentation accompanying your program if you only distribute executables.
36 You must also indicate any changes including additions and deletions to
37 those three files in the documentation.
43 Libav can be combined with a number of external libraries, which sometimes
44 affect the licensing of binaries resulting from the combination.
49 The libcdio, libx264, libx265, libxavs and libxvid libraries are under GPL. When
50 combining them with Libav, Libav needs to be licensed as GPL as well by
51 passing --enable-gpl to configure.
53 The OpenCORE and VisualOn libraries are under the Apache License 2.0. That
54 license is incompatible with the LGPL v2.1 and the GPL v2, but not with
55 version 3 of those licenses. So to combine these libraries with Libav, the
56 license version needs to be upgraded by passing --enable-version3 to configure.
58 incompatible libraries
59 ----------------------
61 The Fraunhofer AAC library, FAAC and OpenSSL are under licenses incompatible
62 with all (L)GPL versions. Thus, unfortunately, since both licenses cannot be
63 satisfied simultaneously, binaries resulting from the combination of Libav
64 with these libraries are nonfree und unredistributable. If you wish to enable
65 any of these libraries nonetheless, pass --enable-nonfree to configure.