mirror of
https://github.com/mpv-player/mpv
synced 2024-12-21 22:30:22 +00:00
394 lines
15 KiB
ReStructuredText
394 lines
15 KiB
ReStructuredText
LUA SCRIPTING
|
|
=============
|
|
|
|
mpv can load Lua scripts. Scripts in ``~/.mpv/lua/`` will be loaded on program
|
|
start, or if passed to ``--lua``. mpv provides the builtin module ``mp``, which
|
|
provides functions to send commands to the mpv core and to retrieve information
|
|
about playback state, user settings, file information, and so on.
|
|
|
|
These scripts can be used to control mpv in a similar way to slave mode.
|
|
Technically, the Lua code uses the client API internally.
|
|
|
|
Example
|
|
-------
|
|
|
|
A script which leaves fullscreen mode when the player is paused:
|
|
|
|
::
|
|
|
|
function on_pause()
|
|
mp.set_property("fullscreen", "no")
|
|
end
|
|
mp.register_event("pause", on_pause)
|
|
|
|
This script provides a pretty weird feature, but Lua scripting was made to
|
|
allow users implement features which are not going to be added to the mpv core.
|
|
|
|
Mode of operation
|
|
-----------------
|
|
|
|
Your script will be loaded by the player at program start from ``~/.mpv/lua/``,
|
|
or ``--lua``, or in some cases, internally (like ``--osc``). Each script runs
|
|
in its own thread. Your script is first run "as is", and once that is done,
|
|
the event loop is entered. This event loop will dispatch events received by mpv
|
|
and call your own event handlers which you have registered with
|
|
``mp.register_event``, or timers added with ``mp.add_timeout`` or similar.
|
|
|
|
When the player quits, all scripts will be asked to terminate. This happens via
|
|
a ``shutdown`` event, which by default will make the event loop return. If your
|
|
script got into an endless loop, mpv will probably behave fine during playback
|
|
(unless the player is suspended, see ``mp.suspend``), but it won't terminate
|
|
when quitting, because it's waiting on your script.
|
|
|
|
Internally, the C code will call the Lua function ``mp_event_loop`` after
|
|
loading a Lua script. This function is normally defined by the default prelude
|
|
loaded before your script (see ``player/lua/defaults.lua`` in the mpv sources).
|
|
The event loop will wait for events and dispatch events registered with
|
|
``mp.register_event``. It will also handle timers added with ``mp.add_timeout``
|
|
and similar (by waiting with a timeout).
|
|
|
|
mp functions
|
|
------------
|
|
|
|
The ``mp`` module is preloaded, although it can be loaded manually with
|
|
``require 'mp'``. It provides the core client API.
|
|
|
|
``mp.command(string)``
|
|
Run the given command. This is similar to the commands used in input.conf.
|
|
See `List of Input Commands`_.
|
|
|
|
Returns true on success, or ``nil, error`` on error.
|
|
|
|
``mp.commandv(arg1, arg2, ...)``
|
|
Similar to ``mp.command``, but pass each command argument as separate
|
|
parameter. This has the advantage that you don't have to care about
|
|
quoting and escaping in some cases.
|
|
|
|
Example:
|
|
|
|
::
|
|
|
|
mp.command("loadfile " .. filename .. " append")
|
|
mp.commandv("loadfile", filename, "append")
|
|
|
|
These two commands are equivalent, except that the first version breaks
|
|
if the filename contains spaces or certain special characters.
|
|
|
|
``mp.get_property(name [,def])``
|
|
Return the value of the given property as string. These are the same
|
|
properties as used in input.conf. See `Properties`_ for a list of
|
|
properties. The returned string is formatted similar to ``${=name}``
|
|
(see `Property Expansion`_).
|
|
|
|
Returns the string on success, or ``def, error`` on error. ``def`` is the
|
|
second parameter provided to the function, and is nil if it's missing.
|
|
|
|
``mp.get_property_osd(name [,def])``
|
|
Similar to ``mp.get_property``, but return the property value formatted for
|
|
OSD. This is the same string as printed with ``${name}`` when used in
|
|
input.conf.
|
|
|
|
Returns the string on success, or ``def, error`` on error. ``def`` is the
|
|
second parameter provided to the function, and is an empty string if it's
|
|
missing. Unlike ``get_property()``, assigning the return value to a variable
|
|
will always result in a string.
|
|
|
|
``mp.set_property(name, value)``
|
|
Set the given property to the given value. See ``mp.get_property`` and
|
|
`Properties`_ for more information about properties.
|
|
|
|
Returns true on success, or ``nil, error`` on error.
|
|
|
|
``mp.get_time()``
|
|
Return the current mpv internal time in seconds as a number. This is
|
|
basically the system time, with an arbitrary offset.
|
|
|
|
``mp.add_key_binding(key, name|fn [,fn])``
|
|
Register callback to be run on a key binding. The binding will be mapped to
|
|
the given ``key``, which is a string describing the physical key. This uses
|
|
the same key names as in input.conf, and also allows combinations
|
|
(e.g. ``ctrl+a``).
|
|
|
|
After calling this function, key presses will cause the function ``fn`` to
|
|
be called (unless the user overmapped the key with another binding).
|
|
|
|
The ``name`` argument should be a short symbolic string. It allows the user
|
|
to remap the key binding via input.conf using the ``script_message``
|
|
command, the script name, and the name of the key binding (see below for
|
|
an example). The name should be unique across other bindings in the same
|
|
script - if not, the previous binding with the same name will be
|
|
overwritten. You can omit the name, in which case a random name is generated
|
|
internally.
|
|
|
|
Internally, key bindings are dispatched via the ``script_message`` input
|
|
command and ``mp.register_script_command``.
|
|
|
|
Trying to map multiple commands to a key will essentially prefer a random
|
|
binding, while the other bindings are not called. It is guaranteed that
|
|
user defined bindings in the central input.conf are preferred over bindings
|
|
added with this function (but see ``mp.add_forced_key_binding``).
|
|
|
|
Example:
|
|
|
|
::
|
|
|
|
function something_handler()
|
|
print("the key was pressed")
|
|
end
|
|
mp.add_key_binding("x", "something", something_handler)
|
|
|
|
This will print the message ``the key was pressed`` when ``x`` was pressed.
|
|
|
|
The user can remap these key bindings. Assume the above script was using
|
|
the filename ``fooscript.lua``, then the user has to put the following
|
|
into his input.conf to remap the command to the ``y`` key:
|
|
|
|
::
|
|
|
|
y script_message lua/fooscript something
|
|
|
|
This will print the message when the key ``y`` is pressed. (``x`` will
|
|
still work, unless the user overmaps it.)
|
|
|
|
``mp.add_forced_key_binding(...)``
|
|
This works almost the same as ``mp.add_key_binding``, but registers the
|
|
key binding in a way that will overwrite the user's custom bindings in his
|
|
input.conf. (``mp.add_key_binding`` overwrites default key bindings only,
|
|
but not those by the user's input.conf.)
|
|
|
|
``mp.remove_key_binding(name)``
|
|
Remove a key binding added with ``mp.add_key_binding`` or
|
|
``mp.add_forced_key_binding``. Use the same name as you used when adding
|
|
the bindings. It's not possible to remove bindings for which you omitted
|
|
the name.
|
|
|
|
``mp.register_event(name, fn)``
|
|
Call a specific function when an event happens. The event name is a string,
|
|
and the function fn is a Lua function value.
|
|
|
|
Some events have associated data. This is put into a Lua table and passed
|
|
as argument to fn. The Lua table by default contains a ``name`` field,
|
|
which is a string containing the event name. If the event has an error
|
|
associated, the ``error`` field is set to a string describing the error,
|
|
on success it's not set.
|
|
|
|
If multiple functions are registered for the same event, they are run in
|
|
registration order, which the first registered function running before all
|
|
the other ones.
|
|
|
|
Returns true if such an event exists, false otherwise.
|
|
|
|
See `Events`_ and `List of events`_ for details.
|
|
|
|
``mp.add_timeout(seconds, fn)``
|
|
Call the given function fn when the given number of seconds has elapsed.
|
|
Note that the number of seconds can be fractional. As of now, the timer
|
|
precision may be as worse as 50 ms, though. (This will be improved in the
|
|
future.)
|
|
|
|
This is a one-shot timer: it will be removed when it's fired.
|
|
|
|
Returns a timer handle. See ``mp.cancel_timer``.
|
|
|
|
``mp.add_periodic_timer(seconds, fn)``
|
|
Call the given function periodically. This is like ``mp.add_timeout``, but
|
|
the timer is re-added after the function fn is run.
|
|
|
|
Returns a timer handle. See ``mp.cancel_timer``.
|
|
|
|
``mp.cancel_timer(t)``
|
|
Terminate the given timer. t is a timer handle (value returned by
|
|
``mp.add_timeout`` or ``mp.add_periodic_timer``).
|
|
|
|
``mp.get_opt(key)``
|
|
Return a setting from the ``--lua-opts`` option. It's up to the user and
|
|
the script how this mechanism is used. Currently, all scripts can access
|
|
this equally, so you should be careful about collisions.
|
|
|
|
``mp.get_script_name()``
|
|
Return the name of the current script. The name is usually made of the
|
|
filename of the script, with directory and file extension removed, and
|
|
prefixed with ``lua/``. If there are several script which would have the
|
|
same name, it's made unique by appending a number.
|
|
|
|
.. admonition:: Example
|
|
|
|
The script ``/path/to/fooscript.lua`` becomes ``lua/fooscript``.
|
|
|
|
``mp.suspend()``
|
|
Suspend the mpv main loop. There is a long-winded explanation of this in
|
|
the C API function ``mpv_suspend()``. In short, this prevents the player
|
|
from displaying the next video frame, so that you don't get blocked when
|
|
trying to access the player.
|
|
|
|
This is automatically called by the event handler.
|
|
|
|
``mp.resume()``
|
|
Undo one ``mp.suspend()`` call. ``mp.suspend()`` increments an internal
|
|
counter, and ``mp.resume()`` decrements it. When 0 is reached, the player
|
|
is actually resumed.
|
|
|
|
``mp.resume_all()``
|
|
This resets the internal suspend counter and resumes the player. (It's
|
|
like calling ``mp.resume()`` until the player is actually resumed.)
|
|
|
|
You might want to call this if you're about to do something that takes a
|
|
long time, but doesn't really need access to the player (like a network
|
|
operation). Note that you still can access the player at any time.
|
|
|
|
``mp.enable_messages(level)``
|
|
Set the minimum log level of which mpv message output to receive. These
|
|
messages are normally printed to the terminal. By calling this function,
|
|
you can set the minimum log level of messages which should be received with
|
|
the ``log-message`` event. See the description of this event for details.
|
|
The level is a string, see ``msg.log`` for allowed log levels.
|
|
|
|
``mp.register_script_command(name, fn)``
|
|
This is a helper to dispatch ``script_message`` invocations to Lua
|
|
functions. ``fn`` is called if ``script_message`` is called on this script
|
|
with ``name`` as first parameter. The other parameters are passed to ``fn``.
|
|
If a command with the given name is already registered, it's overwritten.
|
|
|
|
Used by ``mp.add_key_binding``, so be careful about name collisions.
|
|
|
|
``mp.unregister_script_command(name)``
|
|
Undo a previous registration with ``mp.register_script_command``. Does
|
|
nothing if the ``name`` wasn't registered.
|
|
|
|
mp.msg functions
|
|
----------------
|
|
|
|
This module allows outputting messages to the terminal, and can be loaded
|
|
with ``require 'mp.msg'``.
|
|
|
|
``msg.log(level, ...)``
|
|
The level parameter is the message priority. It's a string and one of
|
|
``fatal``, ``error``, ``warn``, ``info``, ``v``, ``debug``. The user's
|
|
settings will determine which of these messages will be visible. Normally,
|
|
all messages are visible, except ``v`` and ``debug``.
|
|
|
|
The parameters after that are all converted to strings. Spaces are inserted
|
|
to separate multiple parameters.
|
|
|
|
You don't need to add newlines.
|
|
|
|
``msg.fatal(...)``, ``msg.error(...)``, ``msg.warn(...)``, ``msg.info(...)``, ``msg.verbose(...)``, ``msg.debug(...)``
|
|
All of these are shortcuts and equivalent to the corresponding
|
|
``msg.log(level, ...)`` call.
|
|
|
|
Events
|
|
------
|
|
|
|
Events are notifications from player core to scripts. You can register an
|
|
event handler with ``mp.register_event``.
|
|
|
|
Note that all scripts (and other parts of the player) receive events equally,
|
|
and there's no such thing as blocking other scripts from receiving events.
|
|
|
|
Example:
|
|
|
|
::
|
|
|
|
function my_fn(event)
|
|
print("start of playback!")
|
|
end
|
|
|
|
mp.register_event("playback-start", my_fn)
|
|
|
|
|
|
|
|
List of events
|
|
--------------
|
|
|
|
``start-file``
|
|
Happens right before a new file is loaded. When you receive this, the
|
|
player is loading the file (or possibly already done with it).
|
|
|
|
``end-file``
|
|
Happens after a file was unloaded. Typically, the player will load the
|
|
next file right away, or quit if this was the last file.
|
|
|
|
``playback-start``
|
|
Happens atfer a file was loaded and begins playback.
|
|
|
|
``tracks-changed``
|
|
The list of video/audio/sub tracks was updated. (This happens on playback
|
|
start, and very rarely during playback.)
|
|
|
|
``track-switched``
|
|
A video/audio/subtitle track was switched on or off. This usually happens
|
|
when the user (or a script) changes the subtitle track and so on.
|
|
|
|
``idle``
|
|
Idle mode is entered. This happens when playback ended, and the player was
|
|
started with ``--idle`` or ``--force-window``. This mode is implicitly ended
|
|
when the ``start-file`` or ``shutdown`` events happen.
|
|
|
|
``pause``
|
|
Playback was paused.
|
|
|
|
``unpause``
|
|
Playback was unpaused.
|
|
|
|
``tick``
|
|
Called after a video frame was displayed. This is a hack, and you should
|
|
avoid using it. Use timers instead and maybe watch pausing/unpausing events
|
|
to avoid wasting CPU when the player is paused.
|
|
|
|
``shutdown``
|
|
Sent when the player quits, and the script should terminate. Normally
|
|
handled automatically. See `Mode of operation`_.
|
|
|
|
``log-message``
|
|
Receives messages enabled with ``mp.enable_messages``. The message data
|
|
is contained in the table passed as first parameter to the event handler.
|
|
The table contains, in addition to the default event fields, the following
|
|
fields:
|
|
|
|
``prefix``
|
|
The module prefix, identifies the sender of the message. This is what
|
|
the terminal player puts in front of the message text when using the
|
|
``--v`` option, and is also what is used for ``--msglevel``.
|
|
|
|
``level``
|
|
The log level as string. See ``msg.log`` for possible log level names.
|
|
Note that later versions of mpv might add new levels or remove
|
|
(undocumented) existing ones.
|
|
|
|
``text``
|
|
The log message. Note that this is the direct output of a printf()
|
|
style output API. The text will contain embedded newlines, and it's
|
|
possible that a single message contains multiple lines, or that a
|
|
message contains a partial line.
|
|
|
|
It's safe to display messages only if they end with a newline character,
|
|
and to buffer them otherwise.
|
|
|
|
Keep in mind that these messages are meant to be hints for humans. You
|
|
should not parse them, and prefix/level/text of messages might change
|
|
any time.
|
|
|
|
``get-property-reply``
|
|
Undocumented (not useful for Lua scripts).
|
|
|
|
``set-property-reply``
|
|
Undocumented (not useful for Lua scripts).
|
|
|
|
``command-reply``
|
|
Undocumented (not useful for Lua scripts).
|
|
|
|
``script-input-dispatch``
|
|
Undocumented (used internally).
|
|
|
|
``client-message``
|
|
Undocumented (used internally).
|
|
|
|
``video-reconfig``
|
|
Happens on video output or filter reconfig.
|
|
|
|
``audio-reconfig``
|
|
Happens on audio output or filter reconfig.
|
|
|
|
``metadata-update``
|
|
Metadata (like file tags) was updated.
|