mpv/DOCS/tech/slave.txt

SLAVE MODE PROTOCOL
-------------------

The -slave option switches on slave mode, in which MPlayer works as a backend
for other programs. Instead of intercepting keyboard events, MPlayer will read
commands separated by a newline (\n) from stdin.

To try slave mode out by hand, run

  mplayer -slave -quiet <movie>

and type slave commands into the console window.

Most slave mode commands are equivalent to command line options, though not
necessarily under the same name. Detailed descriptions can be found in the
man page.

All commands can be prefixed with one of "pausing ", "pausing_keep ", or
"pausing_toggle ". "pausing " tells MPlayer to pause as soon as possible
after processing the command. "pausing_keep " tells MPlayer to do so only if
it was already in paused mode. "pausing_toggle " tells MPlayer to do so
only if it was not already in paused mode. Please note that "as soon as
possible" can be before the command is fully executed.


Available commands ('mplayer -input cmdlist' will print a list):


alt_src_step <value> (ASX playlist only)
    When more than one source is available it selects the next/previous one.

audio_delay <value>
    Adjust the audio delay by <value> seconds.

[brightness|contrast|gamma|hue|saturation] <value> [<abs>]
    Set/adjust video parameters.
    If abs is not given or is zero, modifies parameter by <value>.
    If abs is non-zero, parameter is set to <value>.
    <value> is in the range [-100, 100].

change_rectangle <val1> <val2>
    Change the position of the rectangle filter rectangle.
        <val1>
            Must be one of the following:
                0 = width
                1 = height
                2 = x position
                3 = y position
        <val2>
            If <val1> is 0 or 1:
                Integer amount to add/subtract from the width/height.
                Positive values add to width/height and negative values
                subtract from it.
            If <val1> is 2 or 3:
                Relative integer amount by which to move the upper left
                rectangle corner. Positive values move the rectangle
                right/down and negative values move the rectangle left/up.

dvb_set_channel <channel_number> <card_number>
    Set DVB channel.

dvdnav <button>
    Press the given dvdnav button.
        1 up
        2 down
        3 left
        4 right
        5 menu
        6 select

dvdnav_event <value>
    Send <value> as DVDNAV event. DVDNAV support in MPlayer is disabled.

edl_mark
    Write the current position into the EDL file.

frame_drop [<value>]
    Toggle/set frame dropping mode.

get_percent_pos
    Print out the current position in the file, as integer percentage [0-100).

get_sub_visibility
    Print out subtitle visibility (1 == on, 0 == off).

get_time_length
    Print out the length of the current file in seconds.

get_time_pos
    Print out the current position in the file in seconds, as float.

get_vo_fullscreen
    Print out fullscreen status (1 == fullscreened, 0 == windowed).

grab_frames
    Currently unimplemented.

screenshot
    Take a screenshot. Requires the screenshot filter to be loaded.

gui_[about|loadfile|loadsubtitle|play|playlist|preferences|skinbrowser|stop]
    GUI actions

key_down_event <value>
	Inject <value> key code event into MPlayer.

loadfile <file|url> <append>
    Load the given file/URL, stopping playback of the current file/URL.
    If <append> is nonzero playback continues and the file/URL is
    appended to the current playlist instead.

loadlist <file> <append>
    Load the given playlist file, stopping playback of the current file.
    If <append> is nonzero playback continues and the playlist file is
    appended to the current playlist instead.

menu <command>
    Execute an OSD menu command.
        up     Move cursor up.
        down   Move cursor down.
        ok     Accept selection.
        cancel Cancel selection.
        hide   Hide the OSD menu.

set_menu <menu_name>
    Display the menu named <menu_name>.

mute
    Mute/unmute sound output.

osd [<level>]
    Toggle OSD mode or set it to level when <level> >= 0.

osd_show_text <string>
    Show <string> on the OSD.

panscan <-1.0 - 1.0> | <0.0 - 1.0> <absolute>
    Increase or decrease the pan-and-scan range by <value>, 1.0 is the maximum.
    Negative values decrease the pan-and-scan range.
    If <absolute> is != 0, then the pan-and scan range is interpreted as an
    absolute range.

pause
    Pause/unpause the playback.

frame_step
    Play one frame, then pause again.

pt_step <value> [<force>]
    Go to the next/previous entry in the playtree. The sign of <value> tells
    the direction.  If no entry is available in the given direction it will do
    nothing unless force is non-zero.

pt_up_step <value> [<force>]
    Similar to pt_step but jumps to the next/previous entry in the parent list.
    Useful to break out of the inner loop in the playtree.

quit [<value>]
    Quit MPlayer. The optional integer value is used as the return code
    for the mplayer process (default: 0).

seek <value> [<type>]
    Seek to some place in the movie.
        0 is a relative seek of +/- <value> seconds (default).
        1 is a seek to <value> % in the movie.
        2 is a seek to an absolute position of <value> seconds.

speed_incr <value>
    Add <value> to the current playback speed.

speed_mult <value>
    Multiply the current speed by <value>.

speed_set <value>
    Set the speed to <value>.

sub_alignment <value>
    Set subtitle alignment.

sub_delay <value> [<abs>]
    Adjust the subtitle delay by +/- <value> seconds or set it to <value>
    seconds when <abs> is nonzero.

sub_load <subtitle_file>
    Loads subtitles from <subtitle_file>.

sub_log
    Logs the current or last displayed subtitle together with filename
    and time information to ~/.mplayer/subtitle_log. Intended purpose
    is to allow convenient marking of bogus subtitles which need to be
    fixed while watching the movie.

sub_pos <value>
    Adjust subtitle position.

sub_remove [<value>]
    If the <value> argument is present and non-negative, removes the subtitle
    file with index <value>. If the argument is omitted or negative, removes
    all subtitle files.

sub_select [<value>]
    Display subtitle with index <value>. Turn subtitle display off if
    <value> is -1 or greater than the highest available subtitle index.
    Cycle through the available subtitles if <value> is omitted or less
    than -1. Supported subtitle sources are -sub options on the command
    line, VOBsubs, DVD subtitles, and Ogg and Matroska text streams.

vobsub_lang
    This is a stub linked to sub_select for backwards compatibility.

sub_step <value>
    Step forward in the subtitle list by <value> steps or backwards if <value>
    is negative.

sub_visibility
    Toggle subtitle visibility.

forced_subs_only
    Display forced subtitles only.

switch_audio [<value>] (MPEG and Matroska only)
    Switch to the audio track with the id <value>. Cycle through the
    available tracks if <value> is omitted or negative.

switch_ratio [<value>]
    Change aspect ratio at runtime. Value is the new aspect ratio expressed
    as a float (e.g. 1.77778 for 16/9).
    There might be problems with some video filters.

switch_vsync [<value>]
    Toggle vsync (1 == on, 0 == off). If no value is provided,
    vsync status is inverted.

tv_step_channel <channel>
    Select next/previous TV channel.

tv_step_norm
    Change TV norm.

tv_step_chanlist
    Change channel list.

tv_set_channel <channel>
    Set the current TV channel.

tv_last_channel
    Set the current TV channel to the last one.

tv_set_freq <frequency in MHz>
    Set the TV tuner frequency.

tv_set_norm <norm>
    Set the TV tuner norm (PAL, SECAM, NTSC, ...).

tv_set_brightness <-100 - 100>
    Set TV tuner brightness.

tv_set_contrast <-100 -100>
    Set TV tuner contrast.

tv_set_hue <-100 - 100>
    Set TV tuner hue.

tv_set_saturation <-100 - 100>
    Set TV tuner saturation.

use_master
    Switch volume control between master and PCM.

vo_border
    Toggle borderless display.

vo_fullscreen
    Switch to fullscreen mode.

vo_ontop
    Toggle stay-on-top.

vo_rootwin
    Toggle playback on the root window.

volume <value>
    Increase/decrease volume.


The following commands are really only useful for OSD menu console mode:

help
    Displays help text, currently empty.

exit
    Exits from OSD menu console. Unlike 'quit', does not quit MPlayer.

hide
    Hides the OSD menu console. Clicking a menu command unhides it. Other
    keybindings act as usual.

run <value>
    Run <value> as shell command. In OSD menu console mode stdout and stdin
    are through the video output driver.