The Music Player Daemon - User's Manual
Introduction
This document is work in progress. Most of it may be incomplete
yet. Please help!
MPD (Music Player Daemon) is, as the name suggests, a server
software allowing you to remotely play your music, handle
playlists, deliver music (HTTP STREAMS with various
sub-protocols) and organizze playlists.
It has been written with minimal resource usage and stability in
mind! Infact, it runs fine on a Pentium 75, allowing you to use
your cheap old PC to create a stereo system!
MPD supports also Gapless playback, buffered audio output, and
crossfading!
The separate client and server design allows users to choose a
user interface that best suites their tastes independently of
the underlying daemon, which actually plays music!
Installation
We recommend that you use the software installation routines of
your distribution to install MPD. Most operating systems have a
MPD package, which is very easy to install.
Installing on Debian/Ubuntu
Install the package mpd via APT:
apt-get install mpd
When installed this way, MPD by default looks for music in
/var/lib/mpd/music/; this may not be correct. Look at your
/etc/mpd.conf file...
Compiling from source
Download the source tarball from the MPD home
page and unpack it:
tar xf mpd-version.tar.xz
cd mpd-version
Make sure that all the required libraries and build tools are
installed. The INSTALL file has a list.
Now configure the source tree:
./configure
The --help argument shows a list of
compile-time options. When everything is ready and
configured, compile:
make
And install:
make install
systemd socket activation
Using systemd, you can launch
mpd on demand when the first client
attempts to connect. Create two files in
/etc/systemd/system/; first
mpd.socket:
[Socket]
ListenStream=/run/mpd.socket
ListenStream=6600
[Install]
WantedBy=sockets.target
Now create mpd.service:
[Unit]
Description=Music Player Daemon
After=sound.target
[Service]
ExecStart=/usr/bin/mpd --stdout --no-daemon
Start the socket:
systemctl enable mpd.socket
systemctl start mpd.socket
In this configuration, mpd will ignore
the bind_to_address and
port settings.
Configuration
Configuring the music directory
When you play local files, you should organize them within a
directory called the "music directory". This is configured in
MPD with the music_directory setting.
By default, MPD follows symbolic links in the music directory.
This behavior can be switched off:
follow_outside_symlinks controls whether
MPD follows links pointing to files outside of the music
directory, and follow_inside_symlinks lets
you disable symlinks to files inside the music directory.
Configuring database plugins
If a music directory is configured, one database plugin is
used. To configure this plugin, add a
database block to
mpd.conf:
database {
plugin "simple"
path "/var/lib/mpd/db"
}
The following table lists the database
options valid for all plugins:
Name
Description
plugin
The name of the plugin.
Configuring input plugins
To configure an input plugin, add a input
block to mpd.conf:
input {
plugin "curl"
proxy "proxy.local"
}
The following table lists the input options
valid for all plugins:
Name
Description
plugin
The name of the plugin.
enabled
yes|no
Allows you to disable a input plugin without
recompiling. By default, all plugins are enabled.
Configuring decoder plugins
Most decoder plugins do not need any special configuration.
To configure a decoder, add a decoder block
to mpd.conf:
decoder {
plugin "wildmidi"
config_file "/etc/timidity/timidity.cfg"
}
The following table lists the decoder
options valid for all plugins:
Name
Description
plugin
The name of the plugin.
enabled
yes|no
Allows you to disable a decoder plugin without
recompiling. By default, all plugins are enabled.
Configuring encoder plugins
Encoders are used by some of the output plugins (such as
shout). The encoder settings are included
in the audio_output section.
Configuring audio outputs
Audio outputs are devices which actually play the audio chunks
produced by MPD. You can configure any number of audio output
devices, but there must be at least one. If none is
configured, MPD attempts to auto-detect. Usually, this works
quite well with ALSA, OSS and on Mac OS X.
To configure an audio output manually, add an
audio_output block to
mpd.conf:
audio_output {
type "alsa"
name "my ALSA device"
device "hw:0"
}
The following table lists the audio_output
options valid for all plugins:
Name
Description
type
The name of the plugin.
name
The name of the audio output. It is visible to the
client. Some plugins also use it internally, e.g. as
a name registered in the PULSE server.
format
Always open the audio output with the specified audio
format (samplerate:bits:channels), regardless of the
format of the input file. This is optional for most
plugins.
Any of the three attributes may be an asterisk to
specify that this attribute should not be enforced,
example: 48000:16:*.
*:*:* is equal to not having
a format specification.
The following values are valid for
bits: 8
(signed 8 bit integer samples),
16, 24 (signed
24 bit integer samples padded to 32 bit),
24_3 (signed 24 bit integer
samples, no padding, 3 bytes per sample),
32 (signed 32 bit integer
samples), f (32 bit floating
point, -1.0 to 1.0).
enabled
yes|no
Specifies whether this audio output is enabled when
MPD is started. By default, all audio outputs are
enabled.
tags
yes|no
If set to "no", then MPD will not send tags to this
output. This is only useful for output plugins that
can receive tags, for example the
httpd output plugin.
always_on
yes|no
If set to "yes", then MPD attempts to keep this audio
output always open. This may be useful for streaming
servers, when you don't want to disconnect all
listeners even when playback is accidentally stopped.
mixer_type
hardware|software|none
Specifies which mixer should be used for this audio
output: the hardware mixer (available for ALSA, OSS
and PulseAudio), the software mixer or no mixer
("none"). By default, the hardware mixer is used for
devices which support it, and none for the others.
replay_gain_handler
software|mixer|none
Specifies how replay gain is applied. The default is
"software", which uses an internal software volume
control. "mixer" uses the configured (hardware) mixer
control. "none" disables replay gain on this audio
output.
Configuring filters
Filters are plugins which modify an audio stream.
To configure a filter, add a filter block
to mpd.conf:
filter {
plugin "volume"
name "software volume"
}
The following table lists the filter
options valid for all plugins:
Name
Description
plugin
The name of the plugin.
name
The name of the filter.
Configuring playlist plugins
Playlist plugins are used to load remote playlists. This is
not related to MPD's playlist directory.
To configure a playlist plugin, add a
playlist_plugin block to
mpd.conf:
playlist_plugin {
name "m3u"
enabled "true"
}
The following table lists the
playlist_plugin options valid for all
plugins:
Name
Description
name
The name of the plugin.
enabled
yes|no
Allows you to disable a input plugin without
recompiling. By default, all plugins are enabled.
Using MPD
The client
After you have installed, configured and started MPD, you
choose a client to control the playback.
The most basic client is mpc, which
provides a command line interface. It is useful in shell
scripts. Many people bind specific mpc
commands to hotkeys.
The MPD
Wiki contains an extensive list of clients to choose
from.
The music directory and the database
The "music directory" is where you store your music files.
MPD stores all relevant meta information about all songs in
its "database". Whenever you add, modify or remove songs in
the music directory, you have to update the database, for
example with mpc:
mpc update
Depending on the size of your music collection and the speed
of the storage, this can take a while.
To exclude a file from the update, create a file called
.mpdignore in its parent directory. Each
line of that file may contain a list of shell wildcards.
The queue
The queue (sometimes called "current playlist") is a list of
songs to be played by MPD. To play a song, add it to the
queue and start playback. Most clients offer an interface to
edit the queue.
Plugin reference
Database plugins
simple
The default plugin. Stores a copy of the database in
memory. A file is used for permanent storage.
Setting
Description
path
The path of the database file.
proxy
Provides access to the database of another MPD instance
using libmpdclient. This is useful
when you run mount the music directory via NFS/SMB, and the
file server already runs a MPD instance. Only the file
server needs to update the database.
Setting
Description
host
The host name of the "master" MPD instance.
port
The port number of the "master" MPD instance.
Input plugins
curl
Opens remote files or streams over HTTP.
Setting
Description
proxy
Sets the address of the HTTP proxy server.
proxy_user,
proxy_password
Configures proxy authentication.
mms
Plays streams with the MMS protocol.
cdio_paranoia
Plays audio CDs. The URI has the form:
"cdda://[DEVICE][/TRACK]". The
simplest form cdda:// plays the whole
disc in the default drive.
Setting
Description
default_byte_order
little_endian|big_endian
If the CD drive does not specify a byte order, MPD
assumes it is the CPU's native byte order. This
setting allows overriding this.
Decoder plugins
dsdiff
Decodes DFF files containing DSDIFF data (e.g. SACD rips).
Setting
Description
lsbitfirst
yes|no
Decode the least significant bit first. Default is
"no".
dsf
Decodes DSF files containing DSDIFF data (e.g. SACD rips).
fluidsynth
MIDI decoder based on libfluidsynth.
Setting
Description
sample_rate
The sample rate that shall be synthesized by the
plugin. Defaults to 48000.
soundfont
The absolute path of the soundfont file. Defaults
to
/usr/share/sounds/sf2/FluidR3_GM.sf2.
mikmod
Module player based on MikMod.
Setting
Description
loop
yes|no
Allow backward loops in modules. Default is
no.
sample_rate
Sets the sample rate generated by
libmikmod. Default is 44100.
modplug
Module player based on MODPlug.
Setting
Description
loop_count
Number of times to loop the module if it uses backward loops.
Default is 0 which prevents looping.
-1 loops forever.
wildmidi
MIDI decoder based on libwildmidi.
Setting
Description
config_file
The absolute path of the timidity config file. Defaults
to
/etc/timidity/timidity.cfg.
Encoder plugins
flac
Encodes into FLAC (lossless).
Setting
Description
compression
Sets the libFLAC compression
level. The levels range from 0 (fastest, least
compression) to 8 (slowest, most compression).
lame
Encodes into MP3 using the LAME library.
Setting
Description
quality
Sets the quality for VBR. 0 is the highest quality,
9 is the lowest quality. Cannot be used with
bitrate.
bitrate
Sets the bit rate in kilobit per second. Cannot be
used with quality.
null
Does not encode anything, passes the input PCM data as-is.
twolame
Encodes into MP2 using the twolame
library.
Setting
Description
quality
Sets the quality for VBR. 0 is the highest quality,
9 is the lowest quality. Cannot be used with
bitrate.
bitrate
Sets the bit rate in kilobit per second. Cannot be
used with quality.
vorbis
Encodes into Ogg Vorbis.
Setting
Description
quality
Sets the quality for VBR. -1 is the lowest quality,
10 is the highest quality. Cannot be used with
bitrate.
bitrate
Sets the bit rate in kilobit per second. Cannot be
used with quality.
wave
Encodes into WAV (lossless).
Output plugins
alsa
The "Advanced Linux Sound Architecture" plugin uses
libasound. It is recommended if you
are using Linux.
Setting
Description
device
NAME
Sets the device which should be used. This can be
any valid ALSA device name. The default value is
"default", which makes
libasound choose a device. It
is recommended to use a "hw" or "plughw" device,
because otherwise, libasound
automatically enables "dmix", which has major
disadvantages (fixed sample rate, poor resampler,
...).
use_mmap
yes|no
If set to yes, then
libasound will try to use
memory mapped I/O.
buffer_time
US
Sets the device's buffer time in microseconds.
Don't change unless you know what you're doing.
period_time
US
Sets the device's period time in microseconds.
Don't change unless you really know what you're
doing.
auto_resample
yes|no
If set to no, then
libasound will not attempt to
resample, handing the responsibility over to MPD.
It is recommended to let MPD resample (with
libsamplerate), because ALSA is quite poor at doing
so.
auto_channels
yes|no
If set to no, then
libasound will not attempt to
convert between different channel numbers.
auto_format
yes|no
If set to no, then
libasound will not attempt to
convert between different sample formats (16 bit, 24
bit, floating point, ...).
dsd_usb
yes|no
If set to yes, then DSD over
USB according to the pro
posed standard by dCS and others is enabled. This wraps
DSD samples in fake 24 bit PCM, and is understood by
some DSD capable products, but may be harmful to
other hardware. Therefore, the default is
no and you can enable the
option at your own risk.
ao
The ao plugin uses the portable
libao library.
Setting
Description
driver
D
The libao driver to use for
audio output. Possible values depend on what libao
drivers are available. See http://www.xiph.org/ao/doc/drivers.html
for information on some commonly used drivers.
Typical values for Linux include "oss" and "alsa09".
The default is "default", which causes libao to
select an appropriate plugin.
options
O
Options to pass to the selected
libao driver.
write_size
O
This specifies how many bytes to write to the audio
device at once. This parameter is to work around a
bug in older versions of libao on sound cards with
very small buffers. The default is 1024.
fifo
The fifo plugin writes raw PCM data to a
FIFO (First In, First Out) file. The data can be read by
another program.
Setting
Description
path
P
This specifies the path of the FIFO to write to.
Must be an absolute path. If the path does not
exist, it will be created when MPD is started, and
removed when MPD is stopped. The FIFO will be
created with the same user and group as MPD is
running as. Default permissions can be modified by
using the builtin shell command "umask". If a FIFO
already exists at the specified path it will be
reused, and will not be removed when MPD is stopped.
You can use the "mkfifo" command to create this, and
then you may modify the permissions to your liking.
jack
The jack plugin connects to a JACK
server.
Setting
Description
client_name
NAME
The name of the JACK client. Defaults to "Music
Player Daemon".
server_name
NAME
Optional name of the JACK server.
autostart
yes|no
If set to yes, then
libjack will automatically
launch the JACK daemon. Disabled by default.
source_ports
A,B
The names of the JACK source ports to be created.
By default, the ports "left" and "right" are
created. To use more ports, you have to tweak this
option.
destination_ports
A,B
The names of the JACK destination ports to connect to.
ringbuffer_size
NBYTES
Sets the size of the ring buffer for each channel.
Do not configure this value unless you know what
you're doing.
httpd
The httpd plugin creates a HTTP server,
similar to ShoutCast / IceCast. HTTP streaming clients like
mplayer can connect to it.
You must configure either quality or
bitrate. It is highly recommended to
configure a fixed format, because a
stream cannot switch its audio format on-the-fly when the
song changes.
Setting
Description
port
P
Binds the HTTP server to the specified port.
bind_to_address
ADDR
Binds the HTTP server to the specified address (IPv4 or
IPv6). Multiple addresses in parallel are not supported.
encoder
NAME
Chooses an encoder plugin,
e.g. vorbis.
quality
Q
Configures the encoder quality (for VBR) in the
range -1 .. 10.
bitrate
BR
Sets a constant encoder bit rate, in kilobit per
second.
max_clients
MC
Sets a limit, number of concurrent clients. When set
to 0 no limit will apply.
null
The null plugin does nothing. It
discards everything sent to it.
Setting
Description
sync
yes|no
If set to no, then the timer
is disabled - the device will accept PCM chunks at
arbitrary rate (useful for benchmarking). The
default behaviour is to play in real time.
oss
The "Open Sound System" plugin is supported on most Unix
platforms.
Setting
Description
device
PATH
Sets the path of the PCM device. If not specified,
then MPD will attempt to open
/dev/sound/dsp and
/dev/dsp.
openal
The "OpenAL" plugin uses libopenal.
It is supported on many platforms.
Setting
Description
device
NAME
Sets the device which should be used. This can be
any valid OpenAL device name. If not specified, then
libopenal will choose a default device.
osx
The "Mac OS X" plugin uses Apple's CoreAudio API.
pipe
The pipe plugin starts a program and
writes raw PCM data into its standard input.
Setting
Description
command
CMD
This command is invoked with the shell.
pulse
The pulse plugin connects to a PulseAudio
server.
Setting
Description
server
HOSTNAME
Sets the host name of the PulseAudio server. By
default, MPD connects to the local PulseAudio
server.
sink
NAME
Specifies the name of the PulseAudio sink MPD should
play on.
roar
The roar plugin connects to a RoarAudio
server.
Setting
Description
server
HOSTNAME
The host name of the RoarAudio server. If not
specified, then MPD will connect to the default
locations.
role
ROLE
The "role" that MPD registers itself as in the
RoarAudio server. The default is "music".
recorder
The recorder plugin writes the audio
played by MPD to a file. This may be useful for recording
radio streams.
You must configure either quality or
bitrate.
Setting
Description
path
P
Write to this file.
encoder
NAME
Chooses an encoder plugin,
e.g. vorbis.
quality
Q
Configures the encoder quality (for VBR) in the
range -1 .. 10.
bitrate
BR
Sets a constant encoder bit rate, in kilobit per
second.
shout
The shout plugin connects to a ShoutCast
or IceCast server. It forwards tags to this server.
You must set a format.
Setting
Description
host
HOSTNAME
Sets the host name of the Shoutcast/Icecast server.
port
PORTNUMBER
Connect to this port number on the specified host.
timeout
SECONDS
Set the timeout for the shout connection in seconds.
Defaults to 2 seconds.
protocol
icecast2|icecast1|shoutcast
Specifies the protocol that wil be used to connect
to the icecast/shoutcast server. The default
is "icecast2".
mount
URI
Mounts the MPD stream in the specified URI.
user
USERNAME
Sets the user name for submitting the stream to the
server. Default is "source".
password
PWD
Sets the password for submitting the stream to the
server.
name
NAME
Sets the name of the stream.
genre
GENRE
Sets the genre of the stream (optional).
description
DESCRIPTION
Sets a short description of the stream (optional).
url
URL
Sets a URL associated with the stream (optional).
public
yes|no
Specifies whether the stream should be "public".
Default is "no".
encoder
PLUGIN
Sets the name of the encoder plugin. Default is
"vorbis". "vorbis" and "lame" are valid encoder
plugins (provided that you enabled them at compile
time).
solaris
The "Solaris" plugin runs only on SUN Solaris, and plays via
/dev/audio.
Setting
Description
device
PATH
Sets the path of the audio device, defaults to
/dev/audio.
Playlist plugins
embcue
Reads CUE sheets from the "CUESHEET" tag of song files.
m3u
Reads .m3u playlist files.
extm3u
Reads extended .m3u playlist files.
pls
Reads .pls playlist files.
xspf
Reads XSPF
playlist files.