| # License |
| |
| Most files in FFmpeg are under the GNU Lesser General Public License version 2.1 |
| or later \(LGPL v2.1\+\). Read the file `COPYING.LGPLv2.1` for details. Some other |
| files have MIT\/X11\/BSD-style licenses. In combination the LGPL v2.1\+ applies to |
| FFmpeg. |
| |
| Some optional parts of FFmpeg are licensed under the GNU General Public License |
| version 2 or later \(GPL v2\+\). See the file `COPYING.GPLv2` for details. None of |
| these parts are used by default, you have to explicitly pass `--enable-gpl` to |
| configure to activate them. In this case, FFmpeg's license changes to GPL v2\+. |
| |
| Specifically, the GPL parts of FFmpeg are: |
| |
| - libpostproc |
| - optional x86 optimization in the files |
| - `libavcodec\/x86\/flac_dsp_gpl.asm` |
| - `libavcodec\/x86\/idct_mmx.c` |
| - `libavfilter\/x86\/vf_removegrain.asm` |
| - the following building and testing tools |
| - `compat\/solaris\/make_sunver.pl` |
| - `doc\/t2h.pm` |
| - `doc\/texi2pod.pl` |
| - `libswresample\/swresample-test.c` |
| - `tests\/checkasm\/\*` |
| - `tests\/tiny_ssim.c` |
| - the following filters in libavfilter: |
| - `vf_blackframe.c` |
| - `vf_boxblur.c` |
| - `vf_colormatrix.c` |
| - `vf_cover_rect.c` |
| - `vf_cropdetect.c` |
| - `vf_delogo.c` |
| - `vf_eq.c` |
| - `vf_find_rect.c` |
| - `vf_fspp.c` |
| - `vf_geq.c` |
| - `vf_histeq.c` |
| - `vf_hqdn3d.c` |
| - `vf_interlace.c` |
| - `vf_kerndeint.c` |
| - `vf_mcdeint.c` |
| - `vf_mpdecimate.c` |
| - `vf_owdenoise.c` |
| - `vf_perspective.c` |
| - `vf_phase.c` |
| - `vf_pp.c` |
| - `vf_pp7.c` |
| - `vf_pullup.c` |
| - `vf_repeatfields.c` |
| - `vf_sab.c` |
| - `vf_smartblur.c` |
| - `vf_spp.c` |
| - `vf_stereo3d.c` |
| - `vf_super2xsai.c` |
| - `vf_tinterlace.c` |
| - `vf_uspp.c` |
| - `vsrc_mptestsrc.c` |
| |
| Should you, for whatever reason, prefer to use version 3 of the \(L\)GPL, then |
| the configure parameter `--enable-version3` will activate this licensing option |
| for you. Read the file `COPYING.LGPLv3` or, if you have enabled GPL parts, |
| `COPYING.GPLv3` to learn the exact legal terms that apply in this case. |
| |
| There are a handful of files under other licensing terms, namely: |
| |
| \* The files `libavcodec\/jfdctfst.c`, `libavcodec\/jfdctint_template.c` and |
| `libavcodec\/jrevdct.c` are taken from libjpeg, see the top of the files for |
| licensing details. Specifically note that you must credit the IJG in the |
| documentation accompanying your program if you only distribute executables. |
| You must also indicate any changes including additions and deletions to |
| those three files in the documentation. |
| \* `tests\/reference.pnm` is under the expat license. |
| |
| |
| ## External libraries |
| |
| FFmpeg can be combined with a number of external libraries, which sometimes |
| affect the licensing of binaries resulting from the combination. |
| |
| ### Compatible libraries |
| |
| The following libraries are under GPL: |
| - frei0r |
| - libcdio |
| - librubberband |
| - libvidstab |
| - libx264 |
| - libx265 |
| - libxavs |
| - libxvid |
| |
| When combining them with FFmpeg, FFmpeg needs to be licensed as GPL as well by |
| passing `--enable-gpl` to configure. |
| |
| The OpenCORE and VisualOn libraries are under the Apache License 2.0. That |
| license is incompatible with the LGPL v2.1 and the GPL v2, but not with |
| version 3 of those licenses. So to combine these libraries with FFmpeg, the |
| license version needs to be upgraded by passing `--enable-version3` to configure. |
| |
| ### Incompatible libraries |
| |
| There are certain libraries you can combine with FFmpeg whose licenses are not |
| compatible with the GPL and\/or the LGPL. If you wish to enable these |
| libraries, even in circumstances that their license may be incompatible, pass |
| `--enable-nonfree` to configure. But note that if you enable any of these |
| libraries the resulting binary will be under a complex license mix that is |
| more restrictive than the LGPL and that may result in additional obligations. |
| It is possible that these restrictions cause the resulting binary to be |
| unredistributable. |
| |
| The Fraunhofer FDK AAC and OpenSSL libraries are under licenses which are |
| incompatible with the GPLv2 and v3. To the best of our knowledge, they are |
| compatible with the LGPL. |
| |
| The NVENC library, while its header file is licensed under the compatible MIT |
| license, requires a proprietary binary blob at run time, and is deemed to be |
| incompatible with the GPL. We are not certain if it is compatible with the |
| LGPL, but we require `--enable-nonfree` even with LGPL configurations in case |
| it is not. |