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 the project 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+. Source files with specific licenses: - everything under etc/ is unknown - everything under DOCS/man/ is GPLv2+ - sub/osd_font.otf is LGPLv2.1+ - some tests under waftools/fragments/ might be GPLv2+ - version.sh is GPLv2+ Some files are marked with "Almost LGPL." These files are GPL, but all authors have agreed to relicense them to LGPL. the problem is that one of the authors is Michael Niedermayer, who cited the following conditions for relicensing: http://lists.mplayerhq.hu/pipermail/mplayer-dev-eng/2016-September/073535.html We assume the first 3 conditions are fulfilled. The last condition can be interpreted as that his code can be changed to LGPL only as soon as the "core" of mpv changes to LGPL. We interpret "core" as something minimal, that can actually be built and run, with all GPL code disabled. LGPL relicensing status: audio/decode/ad.h LGPL audio/decode/ad_lavc.c very hard (nick's changes) audio/decode/ad_spdif.c very hard (author unreachable) audio/decode/dec_audio.* very hard (nick's changes) audio/filter/af.* must be killed (main author disagreed) audio/filter/af_channel.c must be killed (main author disagreed) audio/filter/af_equalizer.c must be killed (main author disagreed) audio/filter/af_pan.c must be killed (main author disagreed) audio/filter/af_volume.c must be killed (main author disagreed) audio/filter/equalizer.h must be killed (main author disagreed) audio/filter/tools.c must be killed (main author disagreed) audio/filter/af_format.c LGPL audio/filter/af_lavc3enc.c LGPL audio/filter/af_lavfi.c LGPL audio/filter/af_scaletempo.c LGPL audio/filter/af_rubberband.c LGPL audio/out/ao.c hard audio/out/ao.h very hard (anders' changes) audio/out/ao_alsa.c extremely hard (original author did not decide) audio/out/ao_audiounit.m LGPL audio/out/ao_coreaudio.c LGPL audio/out/ao_coreaudio_chmap.c LGPL audio/out/ao_coreaudio_chmap.h LGPL audio/out/ao_coreaudio_exclusiv LGPL audio/out/ao_coreaudio_properti LGPL audio/out/ao_coreaudio_properti LGPL audio/out/ao_coreaudio_utils.c LGPL audio/out/ao_coreaudio_utils.h LGPL audio/out/ao_jack.c unknown audio/out/ao_lavc.c probably easy audio/out/ao_null.c unknown audio/out/ao_openal.c unknown audio/out/ao_opensles.c LGPL audio/out/ao_oss.c will stay GPL audio/out/ao_pcm.c unknown audio/out/ao_pulse.c LGPL audio/out/ao_rsound.c LGPL audio/out/ao_sdl.c LGPL audio/out/ao_sndio.c LGPL (BSD) audio/out/ao_wasapi.c LGPL audio/out/ao_wasapi_changenotif LGPL audio/out/ao_wasapi.h LGPL audio/out/ao_wasapi_utils.c LGPL audio/out/internal.h very hard (anders' changes) audio/out/pull.c unknown audio/out/push.c unknown audio/audio.* very hard (mp_audio based of anders' af_audio) audio/audio_buffer.* LGPL audio/chmap.* LGPL audio/chmap_sel.* LGPL audio/fmt-conversion.* LGPL audio/format.* hard (murky libaf origins) common/av_common.* LGPL common/av_log.c almost LGPL common/av_log.h LGPL common/codecs.* LGPL common/common.* LGPL common/encode.h unknown common/encode_lavc.* unknown common/global.h LGPL common/msg.c almost LGPL common/msg_control.h LGPL common/msg.h LGPL common/playlist.* LGPL common/recorder.* LGPL common/tags.* LGPL common/version.c LGPL demux/codec_tags.* LGPL demux/cue.* LGPL demux/demux.* complications (at least Denes' changes) demux/demux_cue.c LGPL demux/demux_disc.c LGPL demux/demux_edl.c LGPL demux/demux_lavf.c hard demux/demux_libarchive.c LGPL demux/demux_mf.c hard demux/demux_mkv.c LGPL (mostly) demux/demux_mkv_timeline.c LGPL demux/demux_null.c LGPL demux/demux_playlist.c LGPL demux/demux_rar.c LGPL demux/demux_raw.c unknown demux/demux_timeline.c LGPL demux/demux_tv.c will stay GPL demux/ebml.* LGPL demux/matroska.h LGPL demux/packet.* LGPL demux/stheader.h LGPL demux/timeline.* LGPL input/cmd_* unknown, probably easy except some commands input/event.* LGPL input/input.* potentially hard input/ipc.c LGPL input/ipc-unix.c LGPL input/ipc-win.c LGPL input/keycodes.* potentially hard input/pipe-win32.c LGPL libmpv/*.* LGPL misc/*.* LGPL options/m_config.* medium options/m_option.* medium options/m_property.* easy options/options.* very hard (lots of options and history) options/parse_commandline.* easy options/parse_configfile.* easy options/path.* medium osdep/android/* LGPL (BSD) osdep/ar/* LGPL (BSD) osdep/atomic.h LGPL osdep/compiler.h LGPL osdep/endian.h LGPL osdep/glob-win.c LGPL osdep/io.* LGPL osdep/macosx_application.h unknown osdep/macosx_application.m unknown osdep/macosx_application_objc.h unknown osdep/macosx_compat.h unknown osdep/macosx_events.* unknown osdep/macosx_events_objc.h unknown osdep/macosx_touchbar.* unknown osdep/macosx_versions.h unknown osdep/main-fn-cocoa.c LGPL osdep/main-fn.h LGPL osdep/main-fn-unix.c LGPL osdep/main-fn-win.c LGPL osdep/mpv.exe.manifest easy osdep/mpv.rc easy osdep/path.h unknown osdep/path-macosx.m unknown osdep/path-unix.c unknown osdep/path-win.c unknown osdep/semaphore.h LGPL osdep/semaphore_osx.c LGPL osdep/strnlen.h LGPL osdep/subprocess.* LGPL osdep/subprocess-posix.c LGPL osdep/subprocess-win.c LGPL osdep/terminal.h unknown osdep/terminal-unix.c hard osdep/terminal-win.c medium osdep/threads.* LGPL osdep/timer.c LGPL osdep/timer.h LGPL osdep/timer-darwin.c LGPL (MIT) osdep/timer-linux.c LGPL osdep/timer-win2.c LGPL osdep/w32_keyboard.c unknown osdep/w32_keyboard.h unknown osdep/win32-console-wrapper.c LGPL (BSD) osdep/win32/* LGPL (ISC) osdep/windows_utils.* LGPL player/audio.c extremely hard (complex history, libaf ties) player/client.* LGPL (ISC) player/command.c extremely hard (also some GPL-only things) player/command.h hard player/configfiles.c unknown player/core.h extremely hard player/external_files.* hard (murky subreader.c origins) player/lavfi.* LGPL player/loadfile.c extremely hard player/lua/*.* LGPL player/lua.c LGPL player/misc.c LGPL player/osd.c hard player/playloop.c extremely hard player/screenshot.* LGPL player/scripting.* LGPL player/sub.c easy (probably almost no mplayer code) player/video.c extremely hard stream/ai_* will stay GPL (TV code) stream/audio_in.* will stay GPL (TV code) stream/cache.c LGPL 3+ stream/cache_file.c LGPL stream/cookies.* LGPL stream/dvb* must stay GPL stream/frequencies.* must stay GPL stream/rar.* LGPL stream/stream_avdevice.c unknown stream/stream_bluray.c unknown stream/stream.c very hard stream/stream_cb.c LGPL 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_edl.c LGPL stream/stream_file.c LGPL stream/stream.h hard stream/stream_lavf.c hard stream/stream_libarchive.* LGPL stream/stream_memory.c LGPL stream/stream_mf.c unknown stream/stream_null.c LGPL stream/stream_rar.c LGPL stream/stream_smb.c will stay GPLv3 stream/stream_tv.c will stay GPL stream/tv* will stay GPL sub/* LGPL ta/* LGPL (ISC) video/decode/d3d.* LGPL video/decode/dec_video.* hard video/decode/hw_cuda.c LGPL video/decode/hw_d3d11va.c LGPL video/decode/hw_dxva2.c LGPL video/decode/hw_videotoolbox.c LGPL video/decode/lavc.h hard video/decode/vd.h hard video/decode/vd_lavc.c very hard video/filter/refqueue.* LGPL video/filter/vf.c LGPL video/filter/vf.h LGPL (mostly) video/filter/vf_buffer.c LGPL video/filter/vf_crop.c will be deleted video/filter/vf_d3d11vpp.c LGPL video/filter/vf_dlopen.* LGPL video/filter/vf_dsize.c will be deleted video/filter/vf_eq.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_lavfi.* LGPL 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_vapoursynth.c LGPL video/filter/vf_vavpp.c LGPL video/filter/vf_vdpaupp.c LGPL video/filter/vf_yadif.c will be deleted video/csputils.* LGPL video/fmt-conversion.* must be killed (author disagreed to LGPL) video/gpu_memcpy.* will be deleted video/hwdec.* LGPL video/image_writer.* unknown video/img_format.* hard video/img_fourcc.h hard video/mp_image.* hard (if even possible) video/mp_image_pool.* LGPL video/out/aspect.* hard video/out/bitmap_packer.* LGPL video/out/cocoa* unknown video/out/d3d_shader_420p.h LGPL video/out/d3d_shader_nv12.h LGPL video/out/d3d_shader_yuv.hlsl LGPL video/out/dither.* LGPL video/out/drm_common.* LGPL video/out/filter_kernels.* LGPL (BSD) video/out/opengl/hwdec_vaglx.c GPL video/out/opengl/* LGPL video/out/vo.c LGPL video/out/vo.h LGPL video/out/vo_caca.c unknown video/out/vo_direct3d.c unknown video/out/vo_drm.c LGPL video/out/vo_image.c unknown video/out/vo_lavc.c unknown video/out/vo_null.c LGPL video/out/vo_opengl.c LGPL video/out/vo_opengl_cb.c LGPL video/out/vo_rpi.c LGPL video/out/vo_sdl.c LGPL video/out/vo_tct.c LGPL video/out/vo_vaapi.c probably impossible (some company's code) video/out/vo_vdpau.c probably impossible (nVidia's code) video/out/vo_wayland.c LGPL video/out/vo_x11.c probably impossible video/out/vo_xv.c probably impossible video/out/w32_common.* medium video/out/wayland* LGPL video/out/win32/* LGPL video/out/win_state.* unknown video/out/x11_common.* probably impossible video/out/x11_icon.bin must stay GPL video/sws_utils.* LGPL video/vaapi.* hard (GPL-only parts must be ifdefed) video/vdpau.c hard (GPL-only parts must be ifdefed) video/vdpau_functions.inc LGPL video/vdpau.h unknown video/vdpau_mixer.* actual code must be rewritten video/vt.* LGPL