avcodec: Do not lock during init if there is no init function
[libav.git] / LICENSE
1 Libav:
2 ======
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
7 Libav.
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:
19 - vf_blackframe.c
20 - vf_boxblur.c
21 - vf_cropdetect.c
22 - vf_delogo.c
23 - vf_hqdn3d.c
24 - vf_interlace.c
26 Should you, for whatever reason, prefer to use version 3 of the (L)GPL, then
27 the configure parameter --enable-version3 will activate this licensing option
28 for you. Read the file COPYING.LGPLv3 or, if you have enabled GPL parts,
29 COPYING.GPLv3 to learn the exact legal terms that apply in this case.
31 There are a handful of files under other licensing terms, namely:
33 * The files libavcodec/jfdctfst.c, libavcodec/jfdctint_template.c and
34 libavcodec/jrevdct.c are taken from libjpeg, see the top of the files for
35 licensing details. Specifically note that you must credit the IJG in the
36 documentation accompanying your program if you only distribute executables.
37 You must also indicate any changes including additions and deletions to
38 those three files in the documentation.
41 external libraries
42 ==================
44 Libav can be combined with a number of external libraries, which sometimes
45 affect the licensing of binaries resulting from the combination.
47 compatible libraries
48 --------------------
50 The libcdio, libx264, libx265, libxavs and libxvid libraries are under GPL. When
51 combining them with Libav, Libav needs to be licensed as GPL as well by
52 passing --enable-gpl to configure.
54 The OpenCORE and VisualOn libraries are under the Apache License 2.0. That
55 license is incompatible with the LGPL v2.1 and the GPL v2, but not with
56 version 3 of those licenses. So to combine these libraries with Libav, the
57 license version needs to be upgraded by passing --enable-version3 to configure.
59 incompatible libraries
60 ----------------------
62 The Fraunhofer AAC library, FAAC and OpenSSL are under licenses incompatible
63 with all (L)GPL versions. Thus, unfortunately, since both licenses cannot be
64 satisfied simultaneously, binaries resulting from the combination of Libav
65 with these libraries are nonfree und unredistributable. If you wish to enable
66 any of these libraries nonetheless, pass --enable-nonfree to configure.