ffmpeg/LICENSE.md

   1 #FFmpeg:
   2
   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
   6 FFmpeg.
   7
   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+.
  12
  13 Specifically, the GPL parts of FFmpeg are:
  14
  15 - libpostproc
  16 - libmpcodecs
  17 - optional x86 optimizations in the files
  18   libavcodec/x86/flac_dsp_gpl.asm
  19   libavcodec/x86/idct_mmx.c
  20 - libutvideo encoding/decoding wrappers in
  21   libavcodec/libutvideo*.cpp
  22 - the X11 grabber in libavdevice/x11grab.c
  23 - the swresample test app in
  24   libswresample/swresample-test.c
  25 - the texi2pod.pl tool
  26 - the following filters in libavfilter:
  27     - f_ebur128.c
  28     - vf_blackframe.c
  29     - vf_boxblur.c
  30     - vf_colormatrix.c
  31     - vf_cropdetect.c
  32     - vf_decimate.c
  33     - vf_delogo.c
  34     - vf_geq.c
  35     - vf_histeq.c
  36     - vf_hqdn3d.c
  37     - vf_interlace.c
  38     - vf_kerndeint.c
  39     - vf_mcdeint.c
  40     - vf_mp.c
  41     - vf_owdenoise.c
  42     - vf_perspective.c
  43     - vf_phase.c
  44     - vf_pp.c
  45     - vf_pullup.c
  46     - vf_sab.c
  47     - vf_smartblur.c
  48     - vf_spp.c
  49     - vf_stereo3d.c
  50     - vf_super2xsai.c
  51     - vf_tinterlace.c
  52     - vsrc_mptestsrc.c
  53
  54 Should you, for whatever reason, prefer to use version 3 of the (L)GPL, then
  55 the configure parameter --enable-version3 will activate this licensing option
  56 for you. Read the file COPYING.LGPLv3 or, if you have enabled GPL parts,
  57 COPYING.GPLv3 to learn the exact legal terms that apply in this case.
  58
  59 There are a handful of files under other licensing terms, namely:
  60
  61 * The files libavcodec/jfdctfst.c, libavcodec/jfdctint_template.c and
  62   libavcodec/jrevdct.c are taken from libjpeg, see the top of the files for
  63   licensing details. Specifically note that you must credit the IJG in the
  64   documentation accompanying your program if you only distribute executables.
  65   You must also indicate any changes including additions and deletions to
  66   those three files in the documentation.
  67   tests/reference.pnm is under the expat license
  68
  69
  70 external libraries
  71 ==================
  72
  73 FFmpeg can be combined with a number of external libraries, which sometimes
  74 affect the licensing of binaries resulting from the combination.
  75
  76 compatible libraries
  77 --------------------
  78
  79 The following libraries are under GPL:
  80     - frei0r
  81     - libcdio
  82     - libutvideo
  83     - libvidstab
  84     - libx264
  85     - libx265
  86     - libxavs
  87     - libxvid
  88 When combining them with FFmpeg, FFmpeg needs to be licensed as GPL as well by
  89 passing --enable-gpl to configure.
  90
  91 The OpenCORE and VisualOn libraries are under the Apache License 2.0. That
  92 license is incompatible with the LGPL v2.1 and the GPL v2, but not with
  93 version 3 of those licenses. So to combine these libraries with FFmpeg, the
  94 license version needs to be upgraded by passing --enable-version3 to configure.
  95
  96 incompatible libraries
  97 ----------------------
  98
  99 The Fraunhofer AAC library, FAAC and aacplus are under licenses which
 100 are incompatible with the GPLv2 and v3. We do not know for certain if their
 101 licenses are compatible with the LGPL.
 102 If you wish to enable these libraries, pass --enable-nonfree to configure.
 103 But note that if you enable any of these libraries the resulting binary will
 104 be under a complex license mix that is more restrictive than the LGPL and that
 105 may result in additional obligations. It is possible that these
 106 restrictions cause the resulting binary to be unredistributeable.