ffmpeg
# 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/tests/swresample.c` - `tests/checkasm/*` - `tests/tiny_ssim.c` - the following filters in libavfilter: - `signature_lookup.c` - `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_histeq.c` - `vf_hqdn3d.c` - `vf_kerndeint.c` - `vf_lensfun.c` (GPL version 3 or later) - `vf_mcdeint.c` - `vf_mpdecimate.c` - `vf_nnedi.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_signature.c` - `vf_smartblur.c` - `vf_spp.c` - `vf_stereo3d.c` - `vf_super2xsai.c` - `vf_tinterlace.c` - `vf_uspp.c` - `vf_vaguedenoiser.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 version 2: - avisynth - frei0r - libcdio - libdavs2 - librubberband - libvidstab - libx264 - libx265 - libxavs - libxavs2 - libxvid When combining them with FFmpeg, FFmpeg needs to be licensed as GPL as well by passing `--enable-gpl` to configure. The following libraries are under LGPL version 3: - gmp - libaribb24 - liblensfun When combining them with FFmpeg, use the configure option `--enable-version3` to upgrade FFmpeg to the LGPL v3. The VMAF, mbedTLS, RK MPI, 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. The smbclient library is under the GPL v3, to combine it with FFmpeg, the options `--enable-gpl` and `--enable-version3` have to be passed to configure to upgrade FFmpeg to the GPL v3. ### 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. This will 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. ******************************************************************************** libavcodec/arm/jrevdct_arm.S C-like prototype : void j_rev_dct_arm(DCTBLOCK data) With DCTBLOCK being a pointer to an array of 64 'signed shorts' Copyright (c) 2001 Lionel Ulmer (lionel.ulmer@free.fr / bbrox@bbrox.org) Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. ******************************************************************************** libavcodec/arm/vp8dsp_armv6.S VP8 ARMv6 optimisations Copyright (c) 2010 Google Inc. Copyright (c) 2010 Rob Clark <rob@ti.com> Copyright (c) 2011 Mans Rullgard <mans@mansr.com> This file is part of FFmpeg. FFmpeg is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. FFmpeg is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with FFmpeg; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA This code was partially ported from libvpx, which uses this license: Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of Google nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. ******************************************************************************** libavcodec/x86/xvididct.asm XVID MPEG-4 VIDEO CODEC Conversion from gcc syntax to x264asm syntax with modifications by Christophe Gisquet <christophe.gisquet@gmail.com> =========== SSE2 inverse discrete cosine transform =========== Copyright(C) 2003 Pascal Massimino <skal@planet-d.net> Conversion to gcc syntax with modifications by Alexander Strange <astrange@ithinksw.com> Originally from dct/x86_asm/fdct_sse2_skal.asm in Xvid. Vertical pass is an implementation of the scheme: Loeffler C., Ligtenberg A., and Moschytz C.S.: Practical Fast 1D DCT Algorithm with Eleven Multiplications, Proc. ICASSP 1989, 988-991. Horizontal pass is a double 4x4 vector/matrix multiplication, (see also Intel's Application Note 922: http://developer.intel.com/vtune/cbts/strmsimd/922down.htm Copyright (C) 1999 Intel Corporation) More details at http://skal.planet-d.net/coding/dct.html ======= MMX and XMM forward discrete cosine transform ======= Copyright(C) 2001 Peter Ross <pross@xvid.org> Originally provided by Intel at AP-922 http://developer.intel.com/vtune/cbts/strmsimd/922down.htm (See more app notes at http://developer.intel.com/vtune/cbts/strmsimd/appnotes.htm) but in a limited edition. New macro implements a column part for precise iDCT The routine precision now satisfies IEEE standard 1180-1990. Copyright(C) 2000-2001 Peter Gubanov <peter@elecard.net.ru> Rounding trick Copyright(C) 2000 Michel Lespinasse <walken@zoy.org> http://www.elecard.com/peter/idct.html http://www.linuxvideo.org/mpeg2dec/ These examples contain code fragments for first stage iDCT 8x8 (for rows) and first stage DCT 8x8 (for columns) conversion to gcc syntax by Michael Niedermayer ====================================================================== This file is part of FFmpeg. FFmpeg is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. FFmpeg is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with FFmpeg; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA ******************************************************************************** libavformat/oggparsetheora.c Copyright (C) 2005 Matthieu CASTET, Alex Beregszaszi Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. ******************************************************************************** libavutil/x86/x86inc.asm x86inc.asm: x264asm abstraction layer Copyright (C) 2005-2018 x264 project Authors: Loren Merritt <lorenm@u.washington.edu> Henrik Gramner <henrik@gramner.com> Anton Mitrofanov <BugMaster@narod.ru> Fiona Glaser <fiona@x264.com> Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies. THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. ******************************************************************************** libavcodec/jrevdct.c This file is part of the Independent JPEG Group's software. The authors make NO WARRANTY or representation, either express or implied, with respect to this software, its quality, accuracy, merchantability, or fitness for a particular purpose. This software is provided "AS IS", and you, its user, assume the entire risk as to its quality and accuracy. This software is copyright (C) 1994-1996, Thomas G. Lane. All Rights Reserved except as specified below. Permission is hereby granted to use, copy, modify, and distribute this software (or portions thereof) for any purpose, without fee, subject to these conditions: (1) If any part of the source code for this software is distributed, then this README file must be included, with this copyright and no-warranty notice unaltered; and any additions, deletions, or changes to the original files must be clearly indicated in accompanying documentation. (2) If only executable code is distributed, then the accompanying documentation must state that "this software is based in part on the work of the Independent JPEG Group". (3) Permission for use of this software is granted only if the user accepts full responsibility for any undesirable consequences; the authors accept NO LIABILITY for damages of any kind. These conditions apply to any software derived from or based on the IJG code, not just to the unmodified library. If you use our work, you ought to acknowledge us. Permission is NOT granted for the use of any IJG author's name or company name in advertising or publicity relating to this software or products derived from it. This software may be referred to only as "the Independent JPEG Group's software". We specifically permit and encourage the use of this software as the basis of commercial products, provided that all warranty or liability claims are assumed by the product vendor. ******************************************************************************** libavcodec/fft_fixed_32.c libavcodec/fft_init_table.c libavcodec/fft_table.h libavcodec/mips/aacdec_mips.h libavcodec/mips/aacsbr_mips.h libavcodec/mips/compute_antialias_fixed.h libavcodec/mips/compute_antialias_float.h libavutil/fixed_dsp.c libavutil/fixed_dsp.h libavutil/mips/libm_mips.h libavutil/softfloat_tables.h Copyright (c) 2012 MIPS Technologies, Inc., California. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of the MIPS Technologies, Inc., nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE MIPS TECHNOLOGIES, INC. ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE MIPS TECHNOLOGIES, INC. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Authors: Branimir Vasic (bvasic@mips.com) Darko Laus (darko@mips.com) Djordje Pesut (djordje@mips.com) Goran Cordasic (goran@mips.com) Nedeljko Babic (nedeljko.babic imgtec com) Mirjana Vulin (mvulin@mips.com) Stanislav Ocovaj (socovaj@mips.com) Zoran Lukic (zoranl@mips.com) ******************************************************************************** libavformat/oggdec.c libavformat/oggdec.h libavformat/oggparseogm.c libavformat/oggparsevorbis.c Copyright (C) 2005 Michael Ahlberg, Måns Rullgård Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. 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You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA Also add information on how to contact you by electronic and paper mail. You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the library, if necessary. Here is a sample; alter the names: Yoyodyne, Inc., hereby disclaims all copyright interest in the library `Frob' (a library for tweaking knobs) written by James Random Hacker. <signature of Ty Coon>, 1 April 1990 Ty Coon, President of Vice That's all there is to it!