Dudemanguy
f4e89dde36
This is actually a very nice simplification that should have been thought of years ago (sue me). In a nutshell, the story with the wayland code is that the frame callback and swap buffer behavior doesn't fit very well with mpv's rendering loop. It's been refactored/changed quite a few times over the years and works well enough but things could be better. The current iteration works with an external swapchain to check if we have frame callback before deciding whether or not to render. This logic was implemented in both egl and vulkan. This does have its warts however. There's some hidden state detection logic which works but is kind of ugly. Since wayland doesn't allow clients to know if they are actually visible (questionable but whatever), you can just reasonably assume that if a bunch of callbacks are missed in a row, you're probably not visible. That's fine, but it is indeed less than ideal since the threshold is basically entirely arbitrary and mpv does do a few wasteful renders before it decides that the window is actually hidden. The biggest urk in the vo_wayland_wait_frame is the use of wl_display_roundtrip. Wayland developers would probably be offended by the way mpv abuses that function, but essentially it was a way to have semi-blocking behavior needed for display-resample to work. Since the swap interval must be 0 on wayland (otherwise it will block the entire player's rendering loop), we need some other way to wait on vsync. The idea here was to dispatch and poll a bunch of wayland events, wait (with a timeout) until we get frame callback, and then wait for the compositor to process it. That pretty much perfectly waits on vsync and lets us keep all the good timings and all that jazz that we want for mpv. The problem is that wl_display_roundtrip is conceptually a bad function. It can internally call wl_display_dispatch which in certain instances, empty event queue, will block forever. Now strictly speaking, this probably will never, ever happen (once I was able to to trigger it by hardcoding an error into a compositor), but ideally vo_wayland_wait_frame should never infinitely block and stall the player. Unfortunately, removing that function always lead to problems with timings and unsteady vsync intervals so it survived many refactors. Until now, of course. In wayland, the ideal is to never do wasteful rendering (i.e. don't render if the window isn't visible). Instead of wrestling around with hidden states and possible missed vblanks, let's rearrange the wayland rendering logic so we only ever draw a frame when the frame callback is returned to use (within a reasonable timeout to avoid blocking forever). This slight rearrangement of the wait allows for several simplifications to be made. Namely, wl_display_roundtrip stops being needed. Instead, we can rely entirely on totally nonblocking calls (dispatch_pending, flush, and so on). We still need to poll the fd here to actually get the frame callback event from the compositor, but there's no longer any reason to do extra waiting. As soon as we get the callback, we immediately draw. This works quite well and has stable vsync (display-resample and audio). Additionally, all of the logic about hidden states is no longer needed. If vo_wayland_wait_frame times out, it's okay to assume immediately that the window is not visible and skip rendering. Unfortunately, there's one limitation on this new approach. It will only work correctly if the compositor implements presentation time. That means a reduced version of the old way still has to be carried around in vo_wayland_wait_frame. So if the compositor has no presentation time, then we are forced to use wl_display_roundtrip and juggle some funny assumptions about whether or not the window is hidden or not. Plasma is the only real notable compositor without presentation time at this stage so perhaps this "legacy" mechanism could be removed in the future.
mpv
- External links
- Overview
- System requirements
- Downloads
- Changelog
- Compilation
- Release cycle
- Bug reports
- Contributing
- License
- Contact
External links
Overview
mpv is a free (as in freedom) media player for the command line. It supports a wide variety of media file formats, audio and video codecs, and subtitle types.
There is a FAQ.
Releases can be found on the release list.
System requirements
- A not too ancient Linux, Windows 7 or later, or OSX 10.8 or later.
- A somewhat capable CPU. Hardware decoding might help if the CPU is too slow to
decode video in realtime, but must be explicitly enabled with the
--hwdecoption. - A not too crappy GPU. mpv's focus is not on power-efficient playback on
embedded or integrated GPUs (for example, hardware decoding is not even
enabled by default). Low power GPUs may cause issues like tearing, stutter,
etc. The main video output uses shaders for video rendering and scaling,
rather than GPU fixed function hardware. On Windows, you might want to make
sure the graphics drivers are current. In some cases, ancient fallback video
output methods can help (such as
--vo=xvon Linux), but this use is not recommended or supported.
Downloads
For semi-official builds and third-party packages please see mpv.io/installation.
Changelog
There is no complete changelog; however, changes to the player core interface are listed in the interface changelog.
Changes to the C API are documented in the client API changelog.
The release list has a summary of most of the important changes on every release.
Changes to the default key bindings are indicated in restore-old-bindings.conf.
Compilation
Compiling with full features requires development files for several external libraries. Below is a list of some important requirements.
The mpv build system uses waf, but we don't store it in the
repository. The ./bootstrap.py script will download the latest version
of waf that was tested with the build system.
For a list of the available build options use ./waf configure --help. If
you think you have support for some feature installed but configure fails to
detect it, the file build/config.log may contain information about the
reasons for the failure.
NOTE: To avoid cluttering the output with unreadable spam, --help only shows
one of the two switches for each option. If the option is autodetected by
default, the --disable-*** switch is printed; if the option is disabled by
default, the --enable-*** switch is printed. Either way, you can use
--enable-*** or --disable-** regardless of what is printed by --help.
To build the software you can use ./waf build: the result of the compilation
will be located in build/mpv. You can use ./waf install to install mpv
to the prefix after it is compiled.
Example:
./bootstrap.py
./waf configure
./waf
./waf install
Essential dependencies (incomplete list):
- gcc or clang
- X development headers (xlib, xrandr, xext, xscrnsaver, xinerama, libvdpau, libGL, GLX, EGL, xv, ...)
- Audio output development headers (libasound/ALSA, pulseaudio)
- FFmpeg libraries (libavutil libavcodec libavformat libswscale libavfilter and either libswresample or libavresample)
- zlib
- iconv (normally provided by the system libc)
- libass (OSD, OSC, text subtitles)
- Lua (optional, required for the OSC pseudo-GUI and youtube-dl integration)
- libjpeg (optional, used for screenshots only)
- uchardet (optional, for subtitle charset detection)
- nvdec and vaapi libraries for hardware decoding on Linux (optional)
Libass dependencies (when building libass):
- gcc or clang, yasm on x86 and x86_64
- fribidi, freetype, fontconfig development headers (for libass)
- harfbuzz (required for correct rendering of combining characters, particularly for correct rendering of non-English text on OSX, and Arabic/Indic scripts on any platform)
FFmpeg dependencies (when building FFmpeg):
- gcc or clang, yasm on x86 and x86_64
- OpenSSL or GnuTLS (have to be explicitly enabled when compiling FFmpeg)
- libx264/libmp3lame/libfdk-aac if you want to use encoding (have to be explicitly enabled when compiling FFmpeg)
- For native DASH playback, FFmpeg needs to be built with --enable-libxml2 (although there are security implications, and DASH support has lots of bugs).
- AV1 decoding support requires dav1d.
- For good nvidia support on Linux, make sure nv-codec-headers is installed and can be found by configure.
Most of the above libraries are available in suitable versions on normal Linux distributions. For ease of compiling the latest git master of everything, you may wish to use the separately available build wrapper (mpv-build) which first compiles FFmpeg libraries and libass, and then compiles the player statically linked against those.
If you want to build a Windows binary, you either have to use MSYS2 and MinGW, or cross-compile from Linux with MinGW. See Windows compilation.
Release cycle
Every other month, an arbitrary git snapshot is made, and is assigned a 0.X.0 version number. No further maintenance is done.
The goal of releases is to make Linux distributions happy. Linux distributions are also expected to apply their own patches in case of bugs and security issues.
Releases other than the latest release are unsupported and unmaintained.
See the release policy document for more information.
Bug reports
Please use the issue tracker provided by GitHub to send us bug reports or feature requests. Follow the template's instructions or the issue will likely be ignored or closed as invalid.
Using the bug tracker as place for simple questions is fine but IRC is recommended (see Contact below).
Contributing
Please read contribute.md.
For small changes you can just send us pull requests through GitHub. For bigger changes come and talk to us on IRC before you start working on them. It will make code review easier for both parties later on.
You can check the wiki or the issue tracker for ideas on what you could contribute with.
License
GPLv2 "or later" by default, LGPLv2.1 "or later" with --enable-lgpl.
See details.
History
This software is based on the MPlayer project. Before mpv existed as a project, the code base was briefly developed under the mplayer2 project. For details, see the FAQ.
Contact
Most activity happens on the IRC channel and the github issue tracker.
- GitHub issue tracker: issue tracker (report bugs here)
- User IRC Channel:
#mpvonirc.freenode.net - Developer IRC Channel:
#mpv-develonirc.freenode.net