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Command line video player
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wm4 3c123281a7 audio: change format negotiation, remove channel remix fudging 
The audio format neogitation code was pretty complicated, although the
idea was simple: when the format changes (or on the first audio frame),
filter only the new frame through the entire filter chain, discard the
resulting frame, but use the format to initialize the AO.

This was useful for "fudging" the channel remix behavior (upmix or
downmix), and moving it before other filters. Apparently this was useful
for things like DRC filters, which might work better in stereo, and
which also can only achieve the desired volume levels by doing it before
a downmix, which would modify the volume. This mechanism was introduced
in commit 60048b7eb9 (which the commit message also describes as
"idiotic heuristic"). Knowing the output format is inherently necessary
for this, because otherwise we can't know what the hell the user defined
filters will do.

There were problems with robustness. Some filters needed more than one
frame. Resampling in particular would discard initial audio at high
resampling ratios. Some filters might drop audio intentionally (like
clipping data on timestamp ranges). There were also allegations that
some decoders output 0 length frames (although that is invalid in
libavcodec). The state machine was excessively complex and hard to
understand too.

There are 3 things that could have been done:

1. Fix robustness problems by doing more heuristics, like repeating
   audio frames or simply decoding several frames. Since filters can
   behave differently, this would have added lots of complexity.
2. Make use of libavfilter's format negotiation, and add the same to
   mpv builtin filters. This is sort of annoying, because the format
   negotiation in libavfilter changes the state of the filters. It also
   reports only some parameters (mostly all for audio, but a lot of
   holes for video). It would remove some of the state machine, but not
   all.
3. Drop the channel remix fudging, and do the same as the video chain.
   This would not require format negotiation, but instead you can just
   filter the audio frames, and look what comes out of it. If nothing
   comes out, simply never create an AO.

This commit selects option 3. It removes the remix fudging, which means
the loss of a feature. Users can instead add "--af=format=channels=2"
before their DRC filter, or something. I'm also considering changing the
default for --audio-channels back to stereo, and downmix in the decoder
or at the start of the filter chain, which would give the same results,
except requiring more configuration.

Implementation-wise, this is still a bit different from the video path.
The VO always remains the same instance, while the AO might have to be
recreated on configuration changes. This still requires explicit format
change handling + draining old data, but by putting it into
f_autoconvert, not much new code is needed.
2018-04-15 23:11:33 +03:00
.github github: recommend 0x0.st rather than sprunge.us for logfiles 2018-02-16 00:59:25 -08:00
audio ao_pulse: reduce requested device buffer size 2018-04-15 23:11:33 +03:00
common av_common: cosmetic simplification to ffmpeg component iteration loops 2018-04-03 20:08:15 +03:00
demux demux: fix deadlock on "program" property changes 2018-04-15 21:07:13 +03:00
DOCS ao_pulse: reduce requested device buffer size 2018-04-15 23:11:33 +03:00
etc mpv.desktop: fix French translation consistency 2018-03-18 23:01:53 +00:00
filters audio: change format negotiation, remove channel remix fudging 2018-04-15 23:11:33 +03:00
input client API: add a first class hook API, and deprecate old API 2018-03-26 23:02:23 -07:00
libmpv client API: add a first class hook API, and deprecate old API 2018-03-26 23:02:23 -07:00
misc command: use mpv_node helpers instead of duplicated code 2018-03-26 19:47:08 +02:00
options vaapi: add option to select a non-default device path 2018-03-30 14:16:07 -07:00
osdep cocoa-cb: fix shutdown when fullscreen animation is running 2018-03-18 12:11:10 -07:00
player ytdl_hook: don't log error when loading is aborted 2018-04-15 21:07:13 +03:00
stream stream_libarchive: mark as needing cache 2018-04-15 21:07:13 +03:00
sub lavc_conv: do not allow libavcodec to drop subtitles with broken UTF-8 2018-03-26 23:06:51 -07:00
ta ta: introduce talloc_dup() and use it in some places 2018-01-18 01:42:36 -08:00
test tests: stop comparing floats against DBL_EPSILON, use FLT_EPSILON 2018-02-03 13:56:08 -08:00
TOOLS TOOLS/autoload: be more robust with slow directory listings 2018-03-10 12:46:41 +00:00
video vo_gpu: hwdec: Use ffnvcodec to load CUDA symbols 2018-04-15 19:31:50 +03:00
waftools build: fixup vendored wayland protocols with variants 2018-04-15 14:09:50 +03:00
.gitignore
.travis.yml Fix recent FFmpeg deprecations 2018-02-13 17:45:29 -08:00
appveyor.yml appveyor: trigger build on pushing to 'ci' 2018-02-11 18:13:12 -08:00
bootstrap.py build: update waf 2017-02-17 18:54:21 +01:00
Copyright Copyright: fix missing word 2018-01-31 03:50:22 +01:00
LICENSE.GPL Copyright: some more licensing clarifications 2017-10-13 15:44:55 +02:00
LICENSE.LGPL Copyright: some more licensing clarifications 2017-10-13 15:44:55 +02:00
mpv_talloc.h
README.md README: mention some semi-required FFmpeg dependencies 2018-03-03 02:38:01 +02:00
RELEASE_NOTES Release 0.28.0 2017-12-25 00:18:05 +01:00
VERSION Update VERSION 2017-12-25 00:23:13 +01:00
version.sh build: move copyright statement to a shared location 2018-01-01 21:05:09 +00:00
wscript vo_gpu: hwdec: Use ffnvcodec to load CUDA symbols 2018-04-15 19:31:50 +03:00
wscript_build.py vo_gpu: hwdec: Use ffnvcodec to load CUDA symbols 2018-04-15 19:31:50 +03:00

README.md

http://mpv.io/

mpv

External links

Overview

mpv is a media player based on MPlayer and mplayer2. It supports a wide variety of video file formats, audio and video codecs, and subtitle types.

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 --hwdec option.
  • A not too crappy GPU. mpv is not intended to be used with bad GPUs. There are many caveats with drivers or system compositors causing tearing, stutter, etc. 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=xv on 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)
  • vdpau and vaapi libraries for hardware decoding on Linux (optional)

Libass dependencies:

  • gcc or clang, yasm on x86 and x86_64
  • fribidi, freetype, fontconfig development headers (for libass)
  • harfbuzz (optional, 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:

  • 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).
  • For good nvidia support on Linux, make sure nv-codec-headers is installed and can be found by configure.
  • Libav also works, but some features will not work. (See section below.)

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.

FFmpeg vs. Libav

Generally, mpv should work with the latest release as well as the git version of both FFmpeg and Libav. But FFmpeg is preferred, and some mpv features work with FFmpeg only (subtitle formats in particular).

FFmpeg ABI compatibility

mpv does not support linking against FFmpeg versions it was not built with, even if the linked version is supposedly ABI-compatible with the version it was compiled against. Expect malfunctions, crashes, and security issues if you do it anyway.

The reason for not supporting this is because it creates far too much complexity with little to no benefit, coupled with absurd and unusable FFmpeg API artifacts.

Newer mpv versions will refuse to start if runtime and compile time FFmpeg library versions mismatch.

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.

Relation to MPlayer and mplayer2

mpv is a fork of MPlayer. Much has changed, and in general, mpv should be considered a completely new program, rather than a MPlayer drop-in replacement.

For details see FAQ entry.

If you are wondering what's different from mplayer2 and MPlayer, an incomplete and largely unmaintained list of changes is located here.

License

GPLv2 "or later" by default, LGPLv2.1 "or later" with --enable-lgpl. See details.

Contact

Most activity happens on the IRC channel and the github issue tracker.

  • GitHub issue tracker: issue tracker (report bugs here)
  • User IRC Channel: #mpv on irc.freenode.net
  • Developer IRC Channel: #mpv-devel on irc.freenode.net

To contact the mpv team in private write to mpv-team@googlegroups.com. Use only if discretion is required.