- Qt 6.11
- Qt WebEngine
- Qt WebEngine Licensing
- ffmpeg
- Qt 6.11.1 Reference Documentation

# ffmpeg

Project Homepage

     # 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&#x27;s license changes to GPL v2+.

     Specifically, the GPL parts of FFmpeg are:

     - 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_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/riscv/h264addpx_rvv.S

     Copyright © 2024 Rémi Denis-Courmont.

     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.

     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS &quot;AS IS&quot;
     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 OWNER 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/riscv/h264dsp_rvv.S

     SPDX-License-Identifier: BSD-2-Clause

     Copyright © 2024 Rémi Denis-Courmont.

     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.

     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS &quot;AS IS&quot;
     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 OWNER 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/riscv/h264idct_rvv.S

     SPDX-License-Identifier: BSD-2-Clause

     Copyright (c) 2024 J. Dekker &lt;jdek@itanimul.li&gt;
     Copyright © 2024 Rémi Denis-Courmont.

     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.

     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS &quot;AS IS&quot;
     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 OWNER 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/riscv/h264qpel_rvv.S

     SPDX-License-Identifier: BSD-2-Clause

     Copyright (c) 2024 Niklas Haas

     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.

     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS &quot;AS IS&quot;
     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 OWNER 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/riscv/startcode_rvb.S

     Copyright © 2024 Rémi Denis-Courmont.

     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.

     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS &quot;AS IS&quot;
     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 OWNER 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/riscv/startcode_rvv.S

     Copyright © 2024 Rémi Denis-Courmont.

     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.

     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS &quot;AS IS&quot;
     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 OWNER 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.

     ********************************************************************************

     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 &quot;Software&quot;), 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 &quot;AS IS&quot;, 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: x86 abstraction layer

      Copyright (C) 2005-2024 x264 project

      Authors: Loren Merritt &lt;lorenm@u.washington.edu&gt;
               Henrik Gramner &lt;henrik@gramner.com&gt;
               Anton Mitrofanov &lt;BugMaster@narod.ru&gt;
               Fiona Glaser &lt;fiona@x264.com&gt;

      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 &quot;AS IS&quot; 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/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&#x27;&#x27; 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, MÃ¥ns RullgÃ¥rd

     Permission is hereby granted, free of charge, to any person
     obtaining a copy of this software and associated documentation
     files (the &quot;Software&quot;), 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 &quot;AS IS&quot;, 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.

     ********************************************************************************

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                How to Apply These Terms to Your New Libraries

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       &lt;signature of Ty Coon&gt;, 1 April 1990
       Ty Coon, President of Vice

     That&#x27;s all there is to it!