mpv is a fork of mplayer2, which is a fork of MPlayer. mpv as a whole is licensed as GPL version 2 or later (see LICENSE). Most source files are GPLv2+, but some files are available under a more liberal license, such as LGPLv2.1+, BSD, MIT, ISC, and possibly others. Look at the copyright header of each source file, and grep the sources for "Copyright" if you need to know details. C source files without Copyright notice are licensed as LGPLv2.1+. Also see the list of files with specific licenses below (not all files can have a standard license header). All new contributions must be LGPLv2.1+ licensed, or if the changes are done on GPL code, must come with the implicit agreement that the project can relicense the code to LGPLv2.1+ at a later point without asking the contributor. (This is a safeguard for making potential relicensing of remaining code to LGPLv2.1+ easier.) Using a more liberal license compatible to LGPLv2.1+ is also ok. For information about authors and contributors, consult the git log, which contains the complete SVN and CVS history as well. Note that mplayer2 as a whole is licensed under GPLv3+. This is because it uses a copy of talloc (part of Samba), which is LGPLv3+, and the next compatible license for this mix is GPLv3+. MPlayer as a whole is licensed under GPLv2 (incompatible to GPLv3!), because some files are licensed to GPLv2 (and _not_ any later version of the license). In particular, this affects the file libmpdemux/demux_ty_osd.c. It is disabled under mplayer2, and has been removed from mpv. "v2.1+" in this context means "version 2.1 or later". Some libraries are GPLv2+ or GPLv3+ only. Building mpv with Samba support makes it GPLv3+. mpv can be built as LGPLv3+ with the --enable-preliminary-lgpl3 configure option. This is a very new switch and it hasn't been confirmed yet whether really all GPL code is excluded (thus preliminary). In addition, it disables a number of useful features, some of them quite central: - no audio filtering, which breaks: --volume, --af, replaygain, pitch correction, fine control about downmix/upmix/resampling behavior - Linux X11 video output - Linux audio output via ALSA (PulseAudio works) - BSD audio output via OSS - NVIDIA/Linux hardware decoding (vdpau, although CUDA usually works) - many builtin video filters (use libavfilter instead) - automatic rotation and stereoscopic video handling - Linux TV input - the --frames option - the add/cycle and sub-add/audio-add/sub-remove/audio-remove commands - video format conversion (if not supported by the VO) - minor features: jack, DVD, CDDA, SMB, CACA, legacy direct3d VO Some of these will be fixed in the future. The lack of the add/cycle commands makes this particularly useless for CLI mode, and most of the appeal of LGPL is for libmpv anyway. Thus it's not recommended to build mpv CLI in LGPL mode at all. Source files with specific licenses: - etc/input.conf is LGPLv2.1+ - etc/builtin.conf is LGPLv2.1+ - etc/encoding-profiles.conf is LGPLv2.1+ - all mpv icons and derived files are LGPLv2.1+ (mpv-icon-8bit-16x16.png etc.) - everything else under etc/ is unknown - everything under DOCS/man/ is GPLv2+ - sub/osd_font.otf is LGPLv2.1+ - version.sh is LGPLv2+ - bootstrap.py is unknown (probably GPLv2+ or LGPLv2+) - the build system (wscript, waftools/*) is LGPLv2+, some parts BSD Some files are LGPLv3+. This is due to the contributions of a single developer going by the SVN username "iive". The chosen license of this project is LGPLv2.1+. The affected files will be changed to LGPLv2.1+ at the earliest opportunity, for example if his contributions disappear by being replaced or removed. All new contributions to these files are implied to be LGPLv2.1+. The following files are still GPL: audio/filter/* will be replaced with new filter chain audio/filter/af_format.c mostly LGPL (except af glue code) audio/filter/af_lavc3enc.c as above audio/filter/af_lavfi.c as above audio/filter/af_scaletempo.c as above audio/filter/af_rubberband.c as above audio/out/ao_alsa.c chaotic history, original author did not decide audio/out/ao_jack.c will stay GPL audio/out/ao_oss.c will stay GPL audio/audio.* needed by af code only demux/demux_tv.c will stay GPL stream/ai_* will stay GPL (TV code) stream/audio_in.* will stay GPL (TV code) stream/dvb* must stay GPL stream/frequencies.* must stay GPL stream/stream_cdda.c unknown stream/stream_dvb.* must stay GPL stream/stream_dvd.c unknown stream/stream_dvd_common.* unknown stream/stream_dvdnav.c unknown stream/stream_smb.c will stay GPLv3 stream/stream_tv.c will stay GPL stream/tv* will stay GPL video/filter/vf_crop.c will be deleted video/filter/vf_dsize.c will be deleted video/filter/vf_expand.c will be deleted video/filter/vf_flip.c will be deleted video/filter/vf_format.c will be deleted video/filter/vf_gradfun.c will be deleted video/filter/vf_mirror.c will be deleted video/filter/vf_noformat.c will be deleted video/filter/vf_pullup.c will be deleted video/filter/vf_rotate.c will be deleted video/filter/vf_scale.c will be deleted video/filter/vf_stereo3d.c will be deleted video/filter/vf_sub.c will be deleted video/filter/vf_yadif.c will be deleted video/out/opengl/hwdec_vaglx.c GPL video/out/vo_caca.c unknown video/out/vo_direct3d.c unknown video/out/vo_vaapi.c probably impossible (some company's code) video/out/vo_vdpau.c probably impossible (nVidia's code) video/out/vo_x11.c probably impossible video/out/vo_xv.c probably impossible video/out/x11_common.* probably impossible video/vdpau.c hard (GPL-only parts must be ifdefed) video/vdpau.h unknown video/vdpau_mixer.* actual code must be rewritten The following files contain some optional GPL code: input/cmd_list.c potentially some commands demux/demux_mkv.c some verbose message options/options.c --frames option options/parse_commandline.c dvd:// expansion player/audio.c libaf glue code player/loadfile.c --frames option (minor but probably fatal) player/osd.c OSD level 3 player/command.c add/cycle command, possible sub-add command player/main.c configuration output The following files are partially LGPLv3+ (otherwise LGPL): demux/demux_mf.c minor autodetection thing stream/cache.c minor cache option changes video/decode/lavc.h split from vd_lavc.c video/decode/vd_lavc.c XvMC influences in get_format()