Mike Brady
78c9331c2c
Rename D-Bus LoudnessFilterActive property to Loudness and friends Update sample D-Bus commands Add D-Bus convolution filter controls -- enable convolution filters to be turned on and off or changed; enable convolution gain to be checked and changed; fix loudness control. Fix D-Bus loudness switch silencing output. Rename LoudnessFiulterActive to Loudness. Add Convolution, ConvolutionGain and ConvolutionImpulseResponseFile properties to the D-Bus interface. Bug fix: correct frame size entry for S24 format
1200 lines
51 KiB
HTML
1200 lines
51 KiB
HTML
<body text="#000000" link="#0000ff" bgcolor="#ffffff"><center><table width="80%">
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<tr><td><h1>shairport-sync</h1>
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<h2>Synchronised Audio Player for iTunes / AirPlay</h2>
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<h2>Synopsis</h2>
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<b>
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shairport-sync <b>[-djvuw]</b>
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<b>[-a </b><em>name</em><b>]</b>
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<b>[-A </b><em>latency</em><b>]</b>
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<b>[-B </b><em>command</em><b>]</b>
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<b>[-c </b><em>configurationfile</em><b>]</b>
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<b>[-E </b><em>command</em><b>]</b>
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<b>[--get-cover-art]</b>
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<b>[--logOutputLevel]</b>
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<b>[-L </b><em>latency</em><b>]</b>
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<b>[-m </b><em>backend</em><b>]</b>
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<b>[--meta-dir=</b><em>directory</em><b>]</b>
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<b>[-o </b><em>backend</em><b>]</b>
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<b>[--password=</b><em>secret</em><b>]</b>
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<b>[-r </b><em>threshold</em><b>]</b>
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<b>[--statistics]</b>
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<b>[-S </b><em>mode</em><b>]</b>
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<b>[-t </b><em>timeout</em><b>]</b>
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<b>[--tolerance=</b><em>frames</em><b>]</b>
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<b>[-- </b><em>audio_backend_options</em><b>]</b>
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<br>
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shairport-sync <b>-k</b><br>
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shairport-sync <b>-h</b><br>
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shairport-sync <b>-V</b><br>
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</b>
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<h2>Description</h2>
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<p>Shairport Sync plays
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audio streamed from iTunes
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or from an AirPlay device to an ALSA-compatible audio output device (available on
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Linux and FreeBSD), to a "sndio" output device (available on OpenBSD, FreeBSD and
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Linux), to a PulseAudio output stream or to Jack Audio.</p>
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<p>Shairport Sync offers full audio synchronisation.
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Full audio synchronisation means that audio is played on the output device at exactly
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the time specified by the audio source.
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This means that if many devices are playing the same stream at the same
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time, all the outputs will stay in synchrony with one another.
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This allows multiple devices to play the same source without getting out of step with
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one another, enabling, for example, simultaneous multi-room operation.
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</p>
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<p>Shairport Sync can stream synchronised audio to a unix
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pipe or to standard output, or to audio systems that do not provide timing
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information. This could perhaps be described as partial audio synchronisation, where
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synchronised audio is provided by Shairport Sync, but what happens to it in the
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subsequent processing chain, before it reaches the listener's ear, is outside the
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control of shairport-sync.</p>
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<p>Shairport Sync can be compiled to stream metadata, including cover art, to a pipe
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or socket.</p>
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<p>Shairport Sync can be compiled to offer a standard MPRIS interface, a "native"
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D-Bus interface and an MQTT client interface. Through these interfaces, it can provide
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metadata, including cover art, and can offer remote control of the audio source.</p>
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<p>Settings can be made using the configuration file (recommended for all new
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installations) or by using command-line options.</p>
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<p>The name of the Shairport Sync executable is <b>shairport-sync</b>.
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Both names are used in these man pages.</p>
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<h2>Configuration File Settings</h2>
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<p>You should use the configuration file for setting up Shairport Sync.
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This file is usually <em>shairport-sync.conf</em> and is generally located in the
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System Configuration Directory, which is normally the <em>/etc</em> directory in
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Linux or the <em>/usr/local/etc</em> directory in BSD unixes.
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You may need to have root privileges to modify it.</p>
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<p>(Note: Shairport Sync may have been compiled to use a different configuration
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directory. You can determine which by performing the command <em>$ shairport-sync
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-V</em>. One of the items in the output string is the value of the
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<b>sysconfdir</b>,
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i.e. the System Configuration Directory.)</p>
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<p>Within the configuraton file, settings are organised into groups, for
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example, there is a "general" group of
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standard settings, and there is an "alsa" group with settings that pertain to the ALSA
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back end. Here is an example of a typical configuration file:</p>
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<p><b>general = {</b></p>
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<p><p><b>name = "Mike's Boombox";</b></p></p>
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<p><p><b>interpolation = "soxr";</b></p></p>
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<p><p><b>password = "secret";</b></p></p>
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<p><p><b>output_backend = "alsa";</b></p></p>
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<p><b>};</b></p>
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<p><b></b></p>
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<p><b>alsa = {</b></p>
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<p><p><b>output_device = "hw:0";</b></p></p>
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<p><p><b>mixer_control_name = "PCM";</b></p></p>
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<p><b>};</b></p>
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<p>Most settings have sensible default values, so -- as in the example above -- users
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generally only need to set (1) the service name, (2) a password (if desired) and
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(3) the output device. If the output device has a mixer that can be used for volume
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control, then (4) the volume control's name should be specified. It is highly
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desirable to use the output device's mixer for volume control, if available --
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response time is reduced to zero and the processor load is reduced. In the example
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above, "soxr" interpolation was also enabled.</p>
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<p>A sample configuration file with all possible settings, but with all of them
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commented out, is installed at <em>shairport-sync.conf.sample</em>, within the
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System Configuration Directory -- <em>/etc</em> in Linux,
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<em>/usr/local/etc</em> in BSD unixes.</p>
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<p>To retain backwards compatibility with previous versions of shairport-sync
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you can use still use command line options, but any new features, etc. will
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be available only via configuration file settings.</p>
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<p>The configuration file is processed using the <em>libconfig</em> library
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-- see <a href = "http://www.hyperrealm.com/libconfig/libconfig_manual.html">http://www.hyperrealm.com/libconfig/libconfig_manual.html</a>.</p>
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<p><b>"GENERAL" SETTINGS</b></p>
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<p>These are the settings available within the <b>general</b> group:</p>
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<p><b>name=</b><em>"service_name"</em><b>;</b></p>
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<p>Use this <em>service_name</em> to identify this player in iTunes, etc.</p>
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<p>The following substitutions are allowed:
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<b>%h</b> for the computer's hostname,
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<b>%H</b> for the computer's hostname with the first letter capitalised (ASCII
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only),
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<b>%v</b> for the shairport-sync version number, e.g. "3.0.1" and
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<b>%V</b> for the shairport-sync version string, e.g.
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"3.0.1-OpenSSL-Avahi-ALSA-soxr-metadata-sysconfdir:/etc".</p>
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<p>The default is "%H", which is replaced by the hostname with the first letter
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capitalised.</p>
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<p><b>password=</b><em>"password"</em><b>;</b></p>
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<p>Require the password <em>password</em> to connect to the service. If you
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leave this setting commented out, no password is needed.</p>
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<p><b>interpolation=</b><em>"mode"</em><b>;</b></p>
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<p>Interpolate, or "stuff", the audio stream using the <em>mode</em>.
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Interpolation here refers to the
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process of adding or removing frames of audio to or from the
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stream sent to the output device to keep it exactly in synchrony
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with the player.
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The default mode, "basic", is normally almost completely inaudible.
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The alternative mode, "soxr", is even less obtrusive but
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requires much more processing power. For this mode, support for
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libsoxr, the SoX Resampler Library, must be selected when
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shairport-sync is compiled.
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</p>
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<p><b>output_backend=</b><em>"backend"</em><b>;</b></p>
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<p>shairport-sync has a number of modules of code ("backends") through which
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audio is output. Normally, the first audio backend that works is selected. This
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setting forces the selection of the specific audio <em>backend</em>. Perform the
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command <b>shairport-sync -h</b> to get a list of available audio backends -- the
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default is the first on this list. Only the "alsa", "sndio" and "pa" backends support
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synchronisation.</p>
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<p><b>mdns_backend=</b><em>"backend"</em><b>;</b></p>
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<p>shairport-sync has a number of modules of code ("backends") for
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interacting with the mDNS service to be used to advertise itself. Normally, the first
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mDNS backend that works is selected. This setting forces the selection of the specific
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mDNS <em>backend</em>. The default is "avahi". Perform the command
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<b>shairport-sync -h</b> to get a list of available mDNS modules.</p>
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<p><b>port=</b><em>portnumber</em><b>;</b></p>
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<p>Use this to specify the <em>portnumber</em> shairport-sync uses to
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listen for service requests from iTunes, etc. The default is port 5000.</p>
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<p><b>udp_port_base=</b><em>portnumber</em><b>;</b></p>
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<p>When shairport-sync starts to play audio, it establises three UDP
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connections to the audio source. Use this setting to specify the starting
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<em>portnumber</em> for these three ports. It will pick the first three unused ports
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starting from <em>portnumber</em>. The default is port 6001.</p>
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<p><b>udp_port_range=</b><em>range</em><b>;</b></p>
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<p>Use this in conjunction with the prevous setting to specify the
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<em>range</em> of ports that can be checked for availability. Only three ports are
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needed.
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The default is 100, thus 100 ports will be checked from port 6001 upwards until three
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are found.</p>
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<p><b>drift_tolerance_in_seconds=</b><em>seconds</em><b>;</b></p>
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<p>Allow playback to drift up to <em>seconds</em> out of exact
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synchronization before attempting to correct it.
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The default is 0.002 seconds, i.e. 2 milliseconds. The smaller the tolerance, the more
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likely it is that overcorrection will occur.
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Overcorrection is when more corrections (insertions and deletions) are made than are
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strictly necessary to keep the stream in sync. Use the <b>statistics</b> setting
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to monitor correction levels. Corrections should not greatly exceed net corrections.
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This setting replaces the deprecated <b>drift</b> setting.
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</p>
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<p><b>resync_threshold_in_seconds=</b><em>threshold</em><b>;</b></p>
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<p>Resynchronise if timings differ by more than <em>threshold</em> seconds.
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If the output timing differs from the source timing by more than
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the threshold, output will be muted and a full resynchronisation
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will occur. The default threshold is 0.050 seconds, i.e. 50
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milliseconds. Specify 0.0 to disable resynchronisation.
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This setting replaces the deprecated <b>resync_threshold</b> setting.
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</p>
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<p><b>ignore_volume_control=</b><em>"choice"</em><b>;</b></p>
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<p>Set this <em>choice</em> to <em>"yes"</em> if you want the volume to
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be at 100% no matter what the source's volume control is set to.
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This might be useful if you want to set the volume on the output device, independently
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of the setting at the source. The default is <em>"no"</em>.</p>
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<p><b>volume_range_db=</b><em>dBvalue</em><b>;</b></p>
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<p>Use this <em>dBvalue</em> to reduce or increase the attenuation range,
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in decibels, between the minimum and maximum volume.</p>
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<p>For example, if a mixer has a minimum volume of -80 dB and a maximum of +20 dB, you
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might wish to use only 60 dB of the 100 dB available.
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This might be because the sound becomes inaudible at the lowest setting and unbearably
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loud at the highest setting --
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indeed, many domestic HiFi systems have a volume control range of just 60 to 80dB.</p>
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<p>Another potential use might be where the range specified by the mixer does not
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match the capabilities of the device.
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For example, the Raspberry Pi's DAC that feeds the built-in audio jack claims a range
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of 106 dB but has a useful range of only about 30 dB.
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The setting allows you to specify the maximum range from highest to lowest.
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The range suggested for the Raspberry Pi's built-in audio DAC, which feeds the
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headphone jack, is 30.
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Using it in this case gives the volume control a much more useful range of
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settings.</p>
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<p>As a third example, you can actually extend the range provided by a mixer.
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Many cheaper DACs have hardware mixers that offer a restricted attenuation range.
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If you specify a volume range greater than the range of the mixer, software
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attenuation and hardware attenuation will be combined to give the specified range.</p>
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<p>If you omit this setting, the native range of the mixer is used.</p>
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<p><b>volume_max_db=</b><em>dBvalue</em><b>;</b></p>
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<p>Specify the maximum output level to be used with the hardware mixer, if
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used. If no hardware mixed is used, this setting specifies the maximum setting
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permissible in the software mixer, which has an attenuation range from 0.0 dB down to
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-96.3 dB.
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</p>
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<p><b>volume_control_profile=</b><em>"choice"</em><b>;</b></p>
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<p>Use this advanced setting to specify how the airplay volume is transferred
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to the mixer volume. The <em>"standard"</em> profile, which is the default, makes
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the volume change more quickly at lower volumes and slower at higher volumes. Choose
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the <em>"flat"</em> profile to makes the volume change at the same rate at all
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volume levels.
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</p>
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<p><b>volume_range_combined_hardware_priority=</b>
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<em>"choice"</em><b>;</b></p>
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<p>Use this advanced setting to specify how to combine the hardware
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attenuator with software attenuation to provide a greater attenuation range than the
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hardware attenuator alone can provide. Choosing <em>"yes"</em> means that when
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attenuation is required, the hardware attenuator will be used in preference.
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If more attenuation than it can provide is needed, the hardware attenuator is set to
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its greatest attenuation and software attenuation is added.</p>
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<p>For example, if 40 dB of attenuation is required and the hardware attenuator
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offers a maximum of 30 dB, then the hardware attenuator will be set to give 30 dB
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attenuation and 10 dB of software attenuation will be added.</p>
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<p>Unfortunately, certain hardware attenuators will mute at their greatest
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attenuation, so can't be combined with software attenuation in this way. Choosing
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<em>"no"</em> means that software attenuation is used to bring the remaining
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attenuation required into the range offered by the hardware attenuator.
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This is the default.
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</p>
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<p><b>run_this_when_volume_is_set=</b>
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<em>"/full/path/to/application/and/args"</em><b>;</b></p>
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<p>Here you can specify a program and its arguments that will be run when the
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volume is set or changed. Be careful to include the full path to the application.
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The application must be marked as executable and, if it is a script, its first line
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must begin with the standard shebang <em>#!/bin/...</em> as appropriate.</p>
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<p>The desired AirPlay volume is appended to the end of the command line -- leave a
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space at the end of the command line you specify here if you want it treated as an
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extra argument.
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AirPlay volume goes from 0.0 to -30.0 and -144.0 means "mute".</p>
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<p><b>regtype=</b><em>"regTypeString"</em><b>;</b></p>
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<p>Use this advanced setting to set the service type and transport to be
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advertised by Zeroconf/Bonjour. Default is <em>"_raop._tcp"</em>.</p>
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<p><b>playback_mode=</b><em>"mode"</em><b>;</b></p>
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<p>The <em>mode</em> can be "stereo", "mono", "reverse stereo", "both left"
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or "both right". Default is "stereo". Note that dither will be added to the signal in
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the mono mode.</p>
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<p><b>alac_decoder=</b><em>"decodername"</em><b>;</b></p>
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<p>This can be "hammerton" or "apple". This advanced setting allows you to
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choose the original Shairport decoder by David Hammerton or the Apple Lossless Audio
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Codec (ALAC) decoder written by Apple. Shairport Sync must have been compiled with the
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configuration setting "--with-apple-alac" and the Apple ALAC decoder library must be
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present for this to work.</p>
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<p><b>interface=</b><em>"name"</em><b>;</b></p>
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<p>Use this advanced setting if you want to confine Shairport Sync to the
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named interface. Leave it commented out to get the default bahaviour.</p>
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<p><b>audio_backend_latency_offset_in_seconds=</b>
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<em>offset_in_seconds</em><b>;</b></p>
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<p>Set this <em>offset_in_seconds</em> to compensate for a fixed delay in
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the audio back end. For example, if the output device delays by 100 ms, set this to
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-0.1.</p>
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<p><b>audio_backend_buffer_desired_length_in_seconds=</b>
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<em>length_in_seconds</em><b>;</b></p>
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<p>Use this <em>length_in_seconds</em> to set the desired length of the
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queue of audio frames in the backend's output buffer.</p>
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<p>The default is 0.15 seconds for the ALSA backend, 0.35 seconds for the PA backend
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and one second for all other backends.</p>
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<p>If this value is set too small, underflow may occur on low-powered machines.
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If set too large, the response times to the volume control may become excessive, or it
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may exceed the backend's buffer size.
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It may need to be larger on low-powered machines that are also performing other tasks,
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such as processing metadata.</p>
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<p><b>audio_backend_buffer_interpolation_threshold_in_seconds=</b>
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<em>time_in_seconds</em><b>;</b></p>
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<p>This is an advanced feature. If the length of the audio backend buffer
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size drops below this, it's a sign that shairport sync can not process frames of audio
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quickly enough. It this threshold is reached, shairport sync will stop using
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time-consuming interpolation like soxr to avoid underruns.</p>
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<p><b>audio_backend_silent_lead_in_time=</b>
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<em>lead_in_time_in_seconds</em><b>;</b></p>
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<p>This is an advanced setting. Use the <em>lead_in_time_in_seconds</em> to
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set the desired length of the period of silence (a "silent lead-in") played before a
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play session begins.</p>
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<p>The purpose of this silent lead-in is to give the backend sufficient time to
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prepare for operation and to make an estimate (and, importantly, to correct the
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estimate) of the exact time at which to begin playing audio to achieve initial
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synchronisation. The value can be from 0.0 up to a maximum of either 4.0 seconds. The
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actual duration will be close to the setting but can not exceed the latency set by the
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client, usually 2 seconds or a little more.</p>
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<p>If the value chosen is too short for synchronised backends such as the ALSA, sndio
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or PA backends, then audio will not be synchronised correctly at the start of play.
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The default is to have a silent lead-in of approximately the same time as the latency
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set by the client.</p>
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<p><b>dbus_service_bus=</b>
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<em>"bus_name"</em><b>;</b></p>
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<p>If shairport sync is compiled with the D-Bus interface, it can offer it on
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the <em>"system"</em> or the <em>"session"</em> D-Bus "bus".
|
|
Use this to specify which. The default is to use the "system" bus.</p>
|
|
|
|
|
|
|
|
<p><b>mpris_service_bus=</b>
|
|
<em>"bus_name"</em><b>;</b></p>
|
|
<p>If shairport sync is compiled with the MPRIS interface, it can offer the
|
|
service on the <em>"system"</em> or the <em>"session"</em> D-Bus "bus".
|
|
Use this to specify which. The default is to use the "system" bus.</p>
|
|
|
|
|
|
<p><b>"SESSIONCONTROL" SETTINGS</b></p>
|
|
|
|
|
|
<p><b>run_this_before_play_begins=</b><em>"/path/to/application and
|
|
args"</em><b>;</b></p>
|
|
<p>Here you can specify a program and its arguments that will be run just
|
|
before a play session begins. Be careful to include the full path to the application.
|
|
The application must be marked as executable and, if it is a script, its first line
|
|
must begin with the standard shebang <em>#!/bin/...</em> as
|
|
appropriate.</p>
|
|
|
|
|
|
|
|
<p><b>run_this_after_play_ends=</b><em>"/path/to/application and
|
|
args"</em><b>;</b></p>
|
|
<p>Here you can specify a program and its arguments that will be run just
|
|
after a play session ends. Be careful to include the full path to the application.
|
|
The application must be marked as executable and, if it is a script, its first line
|
|
must begin with the standard shebang <em>#!/bin/...</em> as
|
|
appropriate.</p>
|
|
|
|
|
|
|
|
<p><b>run_this_before_entering_active_state=</b><em>"/path/to/application and
|
|
args"</em><b>;</b></p>
|
|
<p>Here you can specify a program and its arguments that will be run just
|
|
before shairport-sync goes active.</p>
|
|
|
|
<p>Shairport Sync goes "active" when a play session starts. When the play
|
|
session ends, the system will stay active until the time
|
|
specified in the <b>active_state_timeout</b> setting elapses.
|
|
If a new play session starts before that, the system will remain active. Otherwise,
|
|
the system will go inactive.
|
|
</p>
|
|
|
|
<p>Be careful to include the full path to the application.
|
|
The application must be marked as executable and, if it is a script, its first line
|
|
must begin with the standard shebang <em>#!/bin/...</em> as
|
|
appropriate.</p>
|
|
|
|
|
|
|
|
<p><b>run_this_after_exiting_active_state=</b><em>"/path/to/application and
|
|
args"</em><b>;</b></p>
|
|
<p>Here you can specify a program and its arguments that will be run just
|
|
after shairport-sync goes inactive (see the previous entry for an explanation
|
|
of the idea).
|
|
Be careful to include the full path to the application.
|
|
The application must be marked as executable and, if it is a script, its first line
|
|
must begin with the standard shebang <em>#!/bin/...</em> as
|
|
appropriate.</p>
|
|
|
|
|
|
|
|
<p><b>active_state_timeout=</b><em>seconds</em><b>;</b></p>
|
|
<p>After a play session has ended, the system will remain active for
|
|
<em>seconds</em> seconds. If a new play session starts before this time has elapsed,
|
|
the system will remain active. However, if no new session starts in the interval, the
|
|
system will go inactive at the end of it. The default is 10 seconds.</p>
|
|
|
|
|
|
|
|
<p><b>run_this_if_an_unfixable_error_is_detected=</b><em>"/path/to/application
|
|
and args"</em><b>;</b></p>
|
|
<p>Here you can specify a program and its arguments that will be run if the
|
|
system detects an unfixable error. At present, there are two types of
|
|
unfixable errors. One is where a play session cannot be terminated.
|
|
The second is if an output device has "stalled" -- that is, if an output device
|
|
refuses to accept any more output frames.</p>
|
|
<p>Although the first problem could, in principle, be fixed by restarting
|
|
Shairport Sync, it is usually caused by a malfunctioning output device.
|
|
Typically, the most reliable way to recover from either of these errors
|
|
is to reboot the entire machine.</p>
|
|
<p>Be careful to include the full path to the application.
|
|
The application must be marked as executable and, if it is a script, its first line
|
|
must begin with the standard shebang <em>#!/bin/...</em> as
|
|
appropriate.</p>
|
|
|
|
|
|
|
|
<p><b>wait_for_completion=</b><em>"choice"</em><b>;</b></p>
|
|
<p>Set <em>choice</em> to "yes" to make shairport-sync wait until the
|
|
programs specified in the <b>run_this_...</b> settings have
|
|
completed execution before continuing. The default is "no".</p>
|
|
|
|
|
|
|
|
<p><b>allow_session_interruption=</b><em>"choice"</em><b>;</b></p>
|
|
<p>If <b>choice</b> is set to "yes", then another source will be able to
|
|
interrupt an existing play session and start a new one.
|
|
When set to "no" (the default), other devices attempting to interrupt a session will
|
|
fail, receiving a busy signal.</p>
|
|
|
|
|
|
|
|
<p><b>session_timeout=</b><em>seconds</em><b>;</b></p>
|
|
<p>If a play session has been established and the source disappears without
|
|
warning (such as a device going out of range of a network)
|
|
then wait for the number of seconds specified before ending the session.
|
|
Once the session has terminated, other devices can use it. The default is 120
|
|
seconds.</p>
|
|
|
|
|
|
|
|
<p><b>"ALSA" SETTINGS</b></p>
|
|
<p>These settings are for the ALSA back end, used to communicate with audio output
|
|
devices in the ALSA system. (By the way, you can use tools such as
|
|
<b>alsamixer</b> or <b>aplay</b> to discover what devices are available.)
|
|
Use these settings to select the output device and the mixer control to be used to
|
|
control the output volume.
|
|
You can additionally set the desired size of the output buffer and you can adjust
|
|
overall latency. Here are the <b>alsa</b> group settings:</p>
|
|
|
|
|
|
<p><b>output_device=</b><em>"output_device"</em><b>;</b></p>
|
|
<p>Use the output device called <em>output_device</em>. The default is the
|
|
device called <em>"default"</em>.</p>
|
|
|
|
|
|
|
|
<p><b>mixer_control_name=</b><em>"name"</em><b>;</b></p>
|
|
<p>Specify the <em>name</em> of the mixer control to be used by
|
|
shairport-sync to control the volume.
|
|
The mixer control must be on the mixer device, which by default is the output device.
|
|
If you do not specify a mixer control name, shairport-sync will adjust the volume in
|
|
software.</p>
|
|
|
|
|
|
|
|
<p><b>mixer_device=</b><em>"mixer_device"</em><b>;</b></p>
|
|
<p>By default, the mixer is assumed to be output_device. Use this setting to
|
|
specify a device other than the output device.</p>
|
|
|
|
|
|
|
|
<p><b>output_rate=</b><em>frame rate</em><b>;</b></p>
|
|
<p>Use this setting to specify the frame rate to output to the ALSA device.
|
|
Allowable values are 44100 (default), 88200, 176400 and 352800. The device must have
|
|
the capability to accept the format you specify. There is no particular reason to use
|
|
anything other than 44100 if it is available.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>output_format=</b><em>"format"</em><b>;</b></p>
|
|
<p>Use this setting to specify the format that should be used to send data to
|
|
the ALSA device. Allowable values are "U8", "S8", "S16", "S24", "S24_3LE", "S24_3BE"
|
|
or "S32". The device must have the capability to accept the format you
|
|
specify.</p><p>"S" means signed; "U" means unsigned; BE means big-endian and LE means
|
|
little-endian. Except where stated (using *LE or *BE), endianness matches that of the
|
|
processor. The default is "S16".</p><p>If you are using a hardware mixer, the best
|
|
setting is S16, as audio will pass through Shairport Sync unmodifed except for
|
|
interpolation. If you are using the software mixer, use 32- or 24-bit, if your device
|
|
is capable of it, to get the lowest possible levels of dither.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>disable_synchronization=</b><em>"no"</em><b>;</b></p>
|
|
<p>This is an advanced setting and is for debugging only. Set to
|
|
<em>"yes"</em> to disable synchronization. Default is <em>"no"</em>.
|
|
If you use it to disable synchronisation, then sooner or later you'll experience audio
|
|
glitches due to audio buffer overflow or underflow.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>period_size=</b><em>number</em><b>;</b></p>
|
|
<p>Use this optional advanced setting to set the alsa period size near to
|
|
this value.</p>
|
|
|
|
|
|
|
|
<p><b>buffer_size=</b><em>number</em><b>;</b></p>
|
|
<p>Use this optional advanced setting to set the alsa buffer size near to
|
|
this value.</p>
|
|
|
|
|
|
|
|
<p><b>use_mmap_if_available=</b><em>"yes"</em><b>;</b></p>
|
|
<p> Use this optional advanced setting to control whether MMAP-based output
|
|
is used to communicate with the DAC. Default is <em>"yes"</em>.</p>
|
|
|
|
|
|
|
|
<p><b>mute_using_playback_switch=</b><em>"no"</em><b>;</b></p>
|
|
|
|
<p>This is an advanced setting and the default is <em>"no"</em>. If it is set to
|
|
<em>"yes"</em>, hardware mute will be used where it is available.
|
|
Set it to <em>"no"</em> to prevent the hardware mute being used.</p>
|
|
<p>If Shairport Sync is sharing the output device with other applications, it is best
|
|
to leave this set to <em>"no"</em> for compatibility with those applications.</p>
|
|
<p>Another motivation for this is to allow the ALSA function call
|
|
"snd_mixer_selem_set_playback_switch_all" to be avoided. It is incorrectly implemented
|
|
on certain soundcards, including the emulated card in VMWare Fusion 8.5.</p>
|
|
|
|
|
|
|
|
|
|
<p><b>maximum_stall_time=</b><em>seconds</em><b>;</b></p>
|
|
<p>If an output device fails to accept any audio frames for more than the
|
|
time, in seconds, specified here (0.2 seconds by default),
|
|
it is considered to have malfunctioned. It will result in the
|
|
<b>run_this_if_an_unfixable_error_is_detected</b> program,
|
|
if any, being called.</p>
|
|
<p>Implemented for the ALSA back end only.</p>
|
|
|
|
|
|
|
|
|
|
<p><b>disable_standby_mode=</b><em>"never"</em><b>;</b></p>
|
|
|
|
<p>Shairport Sync has a "Disable Standby" feature to eliminate certain
|
|
faint-but-annoying audible pops and clicks. When activsted, it prevents
|
|
an output device from entering standby mode and thus it minimises standby/busy
|
|
transitions, which can sometimes be heard. Use this setting to control when the
|
|
Disable Standby feature is active: "never" means it will never be activated, "always"
|
|
means it will be active as soon as shairport-sync starts running, and "auto"
|
|
means it will be active while shairport-sync is in the "active" state.</p>
|
|
<p>Shairport Sync goes "active" when a play session starts. When the play
|
|
session ends, the system will stay active until the time
|
|
specified in the active_state_timeout setting elapses.
|
|
If a new play session starts before that, the system will remain active. Otherwise,
|
|
the system will go inactive.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>"SNDIO" SETTINGS</b></p>
|
|
<p>These settings are for the SNDIO back end, used to communicate with audio output
|
|
devices in the SNDIO system.</p>
|
|
|
|
|
|
<p><b>device=</b><em>"snd/0"</em><b>;</b></p>
|
|
<p>Use this optional setting to specify the name of the output device, e.g.
|
|
<em>"snd/0"</em>. The default is to use the SNDIO system's default.</p>
|
|
|
|
|
|
|
|
<p><b>rate=</b><em>44100</em><b>;</b></p>
|
|
<p>Use this optional setting to specify the output rate in frames per second.
|
|
Valid rates are 44100, 88200, 176400 or 352800.
|
|
The output device must have the capability to accept data at the specified rate. The
|
|
default is 44100.</p>
|
|
|
|
|
|
|
|
<p><b>format=</b><em>"S16"</em><b>;</b></p>
|
|
<p>Use this optional setting to specify the output format. Allowable values
|
|
are "U8", "S8", "S16", "S24", "S24_3LE", "S24_3BE" or "S32".
|
|
The device must have the capability to accept the format you specify.</p><p>"S" means
|
|
signed; "U" means unsigned; BE means big-endian and LE means little-endian.
|
|
Except where stated (using *LE or *BE), endianness matches that of the processor. The
|
|
default is "S16".</p><p>
|
|
Since the SNDIO backend does not use a hardware mixer for volume control, dither will
|
|
be introduced into the output if it is less than full volume.
|
|
Thus, (unless you are ignoring the volume control setting),
|
|
consider using 32- or 24-bit output if your device is capable of it, to get the lowest
|
|
possible levels of dither.</p>
|
|
<p>Please note that 32- or 24-bit has not been extensively tested on
|
|
SNDIO.</p>
|
|
|
|
|
|
|
|
<p><b>round=</b><em>value</em><b>;</b></p>
|
|
<p>Use this optional advanced setting to specify the period size of the SNDIO
|
|
channel. If omitted, a SNDIO system default value will be used.</p>
|
|
|
|
|
|
|
|
<p><b>bufsiz=</b><em>value</em><b>;</b></p>
|
|
<p>Use this optional advanced setting to specify the buffer size of the SNDIO
|
|
channel. If omitted, a SNDIO system default value will be used.</p>
|
|
|
|
|
|
<p><b>"PA" SETTINGS</b></p>
|
|
<p>These settings are for the new PulseAudio backend.</p>
|
|
|
|
|
|
<p><b>application_name=</b><em>"Shairport Sync"</em><b>;</b></p>
|
|
<p>Use this to set the name to appear in the Sounds "Applications" tab when
|
|
Shairport Sync is active. The default is the name "Shairport Sync".</p>
|
|
|
|
|
|
<p><b>"PIPE" SETTINGS</b></p>
|
|
<p>These settings are for the PIPE backend, used to route audio to a named unix pipe.
|
|
The audio is in raw CD audio format: PCM 16 bit little endian, 44,100 samples per
|
|
second, interleaved stereo.</p>
|
|
|
|
|
|
<p><b>name=</b><em>"/path/to/pipe"</em><b>;</b></p>
|
|
<p>Use this to specify the name and location of the pipe. The pipe will be
|
|
created and opened when shairport-sync starts up and will be closed upon shutdown.
|
|
Frames of audio will be sent to the pipe in packets of 352 frames and will be
|
|
discarded if the pipe has not have a reader attached.
|
|
The sender will wait for up to five seconds for a packet to be written before
|
|
discarding it.</p>
|
|
|
|
|
|
<p><b>"STDOUT" SETTINGS</b></p>
|
|
<p>There are no settings for the STDOUT backend.</p>
|
|
|
|
<p><b>"AO" SETTINGS</b></p>
|
|
<p>There are no configuration file settings for the AO backend.</p>
|
|
|
|
<p><b>"METADATA" SETTINGS</b></p>
|
|
<p>shairport-sync can process metadata provided by the source, such as Track Number,
|
|
Album Name, cover art, etc. and can provide additional metadata such as volume level,
|
|
pause/resume, etc. It sends the metadata to a pipe, by default
|
|
<em>/tmp/shairport-sync-metadata</em>.
|
|
To process metadata, shairport-sync must have been compiled with metadata support
|
|
included.
|
|
You can check that this is so by running the command <b>$ shairport-sync -V</b>;
|
|
the identification string will contain the word <b>metadata</b>.</p>
|
|
<p>Please note that different sources provide different levels of metadata. Some
|
|
provide a lot; some provide almost none.</p>
|
|
<p>The <b>metadata</b> group of settings allow you to enable metadata handling and
|
|
to control certain aspects of it:</p>
|
|
|
|
|
|
<p><b>enabled=</b><em>"choice"</em><b>;</b></p>
|
|
<p>Set the <em>choice</em> to "yes" to enable shairport-sync to look for
|
|
metadata from the audio source and to forward it, along with metadata generated by
|
|
shairport-sync itself, to the metadata pipe. The default is "no".</p>
|
|
|
|
|
|
|
|
<p><b>include_cover_art=</b><em>"choice"</em><b>;</b></p>
|
|
<p>Set the <em>choice</em> to "yes" to enable shairport-sync to look for
|
|
cover art from the audio source and to include it in the feed to the metadata pipe.
|
|
You must also enable metadata (see above).
|
|
One reason for not including cover art is that the images can sometimes be very large
|
|
and may delay transmission of subsequent metadata through the pipe.
|
|
The default is "no".</p>
|
|
|
|
|
|
|
|
<p><b>pipe_name=</b><em>"filepathname"</em><b>;</b></p>
|
|
<p>Specify the absolute path name of the pipe through which metadata should
|
|
be sent The default is <em>/tmp/shairport-sync-metadata</em>.</p>
|
|
|
|
|
|
|
|
<p><b>socket_address=</b><em>"hostnameOrIP"</em><b>;</b></p>
|
|
<p>If <em>hostnameOrIP</em> is set to a host name or and IP address, UDP
|
|
packets containing metadata will be sent to this address.
|
|
May be a multicast address. Additionally, <em>socket-port</em> must be non-zero and
|
|
<em>enabled</em> must be set to "yes".</p>
|
|
|
|
|
|
|
|
<p><b>socket_port=</b><em>port</em><b>;</b></p>
|
|
<p>If <b>socket_address</b> is set, use <em>port</em> to specify the
|
|
port to send UDP packets to. Must not be zero.</p>
|
|
|
|
|
|
|
|
<p><b>socket_msglength=</b><em>65000</em><b>;</b></p>
|
|
<p>The maximum packet size for any UDP metadata. This must be between 500 or
|
|
65000. The default is 500.</p>
|
|
|
|
|
|
<p><b>"DIAGNOSTICS" SETTINGS</b></p>
|
|
|
|
<p><b>statistics=</b><em>"setting"</em><b>;</b></p>
|
|
<p>Use this <em>setting</em> to enable ("yes") or disable ("no") the output
|
|
of some statistical information on the console or in the log. The default is to
|
|
disable statistics.</p>
|
|
|
|
|
|
|
|
<p><b>log_verbosity=</b><em>0</em><b>;</b></p>
|
|
<p>Use this to specify how much debugging information should be output or
|
|
logged. The value <em>0</em> means no debug information, <em>3</em> means most
|
|
debug information. The default is <em>0</em>.</p>
|
|
|
|
|
|
|
|
|
|
|
|
<h2>Options</h2>
|
|
|
|
<p>This section is about the command-line options available in shairport-sync.</p>
|
|
<p>Note: if you are setting up shairport-sync for the first time or are updating an
|
|
existing installation, you are encouraged to use the configuration file settings
|
|
described above. Most of the command-line options described below
|
|
simply replicate the configuration settings and are retained to provide backward
|
|
compatibility with older installations of shairport-sync.</p>
|
|
|
|
<p>Many command-line options take sensible default values, so you can normally
|
|
ignore most of them. See the EXAMPLES section for typical usages.</p>
|
|
|
|
<p>There are two kinds of command-line options for shairport-sync:
|
|
regular <b>program options</b> and <b>audio backend options</b>.
|
|
Program options are
|
|
always listed first, followed by any audio backend options, preceded by
|
|
a <b>--</b> symbol.</p>
|
|
|
|
<h2>Program Options</h2>
|
|
|
|
<p>These command-line options are used by shairport-sync itself.</p>
|
|
|
|
|
|
|
|
|
|
<p><b>-a </b><em>service name</em><b> | --name=</b><em>service
|
|
name</em></p>
|
|
<p>
|
|
Use this <em>service name</em> to identify this player in iTunes, etc.</p>
|
|
|
|
<p>The following substitutions are allowed:
|
|
<b>%h</b> for the computer's hostname,
|
|
<b>%H</b> for the computer's hostname with the first letter capitalised (ASCII
|
|
only),
|
|
<b>%v</b> for the shairport-sync version number, e.g. "3.0.1" and
|
|
<b>%V</b> for the shairport-sync version string, e.g.
|
|
"3.0.1-OpenSSL-Avahi-ALSA-soxr-metadata-sysconfdir:/etc".</p>
|
|
<p>The default is "%H", which is replaced by the hostname with the first letter
|
|
capitalised.</p>
|
|
|
|
|
|
|
|
|
|
<p><b>-B </b><em>program</em><b> | --on-start=</b><em>program</em></p>
|
|
<p>
|
|
Execute <em>program</em> when playback is about to begin. Specify the
|
|
full path to the program, e.g. <em>/usr/bin/logger</em>.
|
|
Executable scripts can be used, but they must have the appropriate shebang
|
|
(<em>#!/bin/sh</em> in the headline.</p>
|
|
|
|
<p>If you want shairport-sync to wait until the command has
|
|
completed before starting to play, select the <b>-w</b> option as well.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-c </b><em>filename</em><b> | --configfile=</b><em>filename</em></p>
|
|
<p>
|
|
Read configuration settings from <em>filename</em>. The default is to read them from
|
|
the <em>shairport-sync.conf</em> in the System Configuration Directory --
|
|
<em>/etc</em> in Linux, <em>/usr/local/etc</em> in BSD unixes.
|
|
For information about configuration settings, see the "Configuration File Settings"
|
|
section above.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-d | --daemon</b></p>
|
|
<p>
|
|
Instruct shairport-sync to demonise itself. It will write its
|
|
Process ID (PID) to a file, usually at
|
|
<em>/var/run/shairport-sync/shairport-sync.pid</em>, which is used by the
|
|
<b>-k</b>, <b>-D</b> and <b>-R</b> options to locate
|
|
the daemon at a later time. See also the <b>-j</b> option. Only available if
|
|
shaiport-sync has been compiled with libdaemon support.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-E </b><em>program</em><b> | --on-stop=</b><em>program</em></p>
|
|
<p>
|
|
Execute <em>program</em> when playback has ended. Specify the
|
|
full path to the program, e.g. <em>/usr/bin/logger</em>.
|
|
Executable scripts can be used, but they must have the appropriate shebang
|
|
(<em>#!/bin/sh</em> in the headline.</p>
|
|
<p>If you want shairport-sync to wait until the command has
|
|
completed before continuing, select the <b>-w</b> option as well.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>--get-coverart</b></p>
|
|
<p>
|
|
This option requires the <b>--meta-dir</b> option to be set, and enables
|
|
shairport-sync to request cover art from the source and to transmit it through
|
|
the metadata pipe.</p>
|
|
<p>Please note that cover art data may be very large, and may place too great a
|
|
burden on your network.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-h | --help</b></p>
|
|
<p>
|
|
Print brief help message and exit.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-j</b></p>
|
|
<p>
|
|
Instruct shairport-sync to demonise itself. Unlike the <b>-d</b> option, it will
|
|
not write a Process ID (PID) to a file -- it will just (hence the "j") demonise
|
|
itself. Only available if shaiport-sync has been compiled with libdaemon support.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-k | --kill</b></p>
|
|
<p>
|
|
Kill the shairport-sync daemon and exit. (Requires that the daemon has
|
|
written its PID to an agreed file -- see the <b>-d</b> option. Only available if
|
|
shaiport-sync has been compiled with libdaemon support.)
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>--logOutputLevel</b></p>
|
|
<p>
|
|
Use this to log the volume level when the volume is changed. It may be useful if you
|
|
are trying to determine a suitable value for the maximum volume level. Not available
|
|
as a configuration file setting.
|
|
</p>
|
|
|
|
|
|
|
|
|
|
<p><b>-L | --latency=</b><em>latency</em></p>
|
|
<p>
|
|
Use this to set the <em>default latency</em>, in frames, for audio coming from an
|
|
unidentified source or from an iTunes Version 9 or earlier source. The standard value
|
|
for the <em>default latency</em> is 88,200 frames, where there are 44,100
|
|
frames to the second.
|
|
</p>
|
|
<p>Please note that this feature is deprecated and will be removed in a future version
|
|
of shairport-sync.</p>
|
|
|
|
|
|
|
|
|
|
<p><b>--meta-dir=</b><em>directory</em></p>
|
|
<p>
|
|
Listen for metadata coming from the source and send it, along with metadata from
|
|
shairport-sync itself, to a pipe called <em>shairport-sync-metadata</em>
|
|
in the <em>directory</em> you specify. If you add the <b>--get-cover-art</b>
|
|
then cover art will be sent through the pipe too. See <a href = "https://github.com/mikebrady/shairport-sync-metadata-reader">https://github.com/mikebrady/shairport-sync-metadata-reader</a>
|
|
for a sample metadata reader.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-m </b><em>mdnsbackend</em><b> | --mdns=</b><em>mdnsbackend</em></p>
|
|
<p>
|
|
Force the use of the specified mDNS backend to advertise the
|
|
player on the network. The default is to try all mDNS backends until one
|
|
works.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-o </b><em>outputbackend</em><b> |
|
|
--output=</b><em>outputbackend</em></p>
|
|
<p>
|
|
Force the use of the specified output backend to play the audio.
|
|
The default is to try the first one.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-p </b><em>port</em><b> | --port=</b><em>port</em></p>
|
|
<p>
|
|
Listen for play requests on <em>port</em>. The default is to use port
|
|
5000.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>--password=</b><em>secret</em></p>
|
|
<p>
|
|
Require the password <em>secret</em> to be able to connect and stream to the
|
|
service.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-r </b><em>threshold</em><b> | --resync=</b><em>threshold</em></p>
|
|
<p>
|
|
Resynchronise if timings differ by more than <em>threshold</em> frames.
|
|
If the output timing differs from the source timing by more than
|
|
the threshold, output will be muted and a full resynchronisation
|
|
will occur. The default threshold is 2,205 frames, i.e. 50
|
|
milliseconds. Specify <b>0</b> to disable resynchronisation. This setting is
|
|
deprecated and will be removed in a future version of shairport-sync.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>--statistics</b></p>
|
|
<p>
|
|
Print some statistics in the standard output, or in the logfile if in daemon mode.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-S </b><em>mode</em><b> | --stuffing=</b><em>mode</em></p>
|
|
<p>
|
|
Stuff the audio stream using the <em>mode</em>. "Stuffing" refers to the
|
|
process of adding or removing frames of audio to or from the
|
|
stream sent to the output device to keep it exactly in synchrony
|
|
with the player.
|
|
The default mode, <b>basic</b>, is normally almost completely inaudible.
|
|
The alternative mode, <b>soxr</b>, is even less obtrusive but
|
|
requires much more processing power. For this mode, support for
|
|
libsoxr, the SoX Resampler Library, must be selected when
|
|
shairport-sync is compiled.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-t </b><em>timeout</em><b> | --timeout=</b><em>timeout</em></p>
|
|
<p>
|
|
Exit play mode if the stream disappears for more than <em>timeout</em>
|
|
seconds.</p>
|
|
<p>When shairport-sync plays an audio stream, it starts a play
|
|
session and will return a busy signal to any other sources that
|
|
attempt to use it. If the audio stream disappears for longer
|
|
than <em>timeout</em> seconds, the play session will be terminated.
|
|
If you specify a timeout time of <b>0</b>,
|
|
shairport-sync will never signal that
|
|
it is busy and will not prevent other sources from "barging in"
|
|
on an existing play session. The default value is 120 seconds.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>--tolerance=</b><em>frames</em></p>
|
|
<p>
|
|
Allow playback to be up to <em>frames</em> out of exact synchronization before
|
|
attempting to correct it.
|
|
The default is 88 frames, i.e. 2 ms. The smaller the tolerance, the more likely it is
|
|
that overcorrection will occur.
|
|
Overcorrection is when more corrections (insertions and deletions) are made than are
|
|
strictly necessary to keep the stream in sync. Use the <b>--statistics</b> option
|
|
to monitor correction levels. Corrections should not greatly exceed net corrections.
|
|
This setting is deprecated and will be removed in a future version of shairport-sync.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-u</b></p>
|
|
<p>
|
|
If you are running shairport-sync from the command line and want logs to appear there,
|
|
use this option. Otherwise, logs may go to the system log.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-V | --version</b></p>
|
|
<p>
|
|
Print version information and exit.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-v | --verbose</b></p>
|
|
<p>
|
|
Print debug information. Repeat up to three times to get more detail.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-w | --wait-cmd</b></p>
|
|
<p>
|
|
Wait for commands specified using <b>-B</b> or <b>-E</b> to complete before
|
|
continuing execution.
|
|
</p>
|
|
|
|
|
|
<h2>Audio Backend Options</h2>
|
|
|
|
<p>These command-line options are passed to the chosen audio backend. The audio
|
|
backend options are
|
|
preceded by a <b>--</b> symbol to introduce them and to separate them from any
|
|
program options. In this way, option letters can be used as program
|
|
options and also as audio backend options without ambiguity.</p>
|
|
|
|
<p>In the ALSA backend, audio is sent to an output device
|
|
which you can specify using the <b>-d</b> option.
|
|
The output level (the "volume") is controlled using a level control associated with a
|
|
mixer.
|
|
By default, the mixer is implemented in shairport-sync itself in software.
|
|
To use a hardware level control on a mixer on the sound card, specify the name of the
|
|
mixer control with the <b>-c</b> option.
|
|
If the mixer is not associated with the output device, then you need to specify where
|
|
the mixer is to be found with the <b>-m</b> option.</p>
|
|
|
|
|
|
|
|
|
|
<p><b>-c </b><em>controlname</em></p>
|
|
<p>
|
|
Use the level control called <em>controlname</em> on the hardware mixer for
|
|
controlling volume.
|
|
This is needed if the mixer type is specified, using the <b>-t</b> option,
|
|
to be <b>hardware</b>. There is no default.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-d </b><em>device</em></p>
|
|
<p>
|
|
Use the specified output <em>device</em>. You may specify a card, e.g.
|
|
<b>hw:0</b>, in which case the default output device on the card will be chosen.
|
|
Alternatively, you can specify a specific device on a card, e.g. <b>hw:0,0</b>.
|
|
The default is the device named <b>default</b>.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-m </b><em>mixer</em></p>
|
|
<p>
|
|
Use the specified hardware <em>mixer</em> for volume control. Use this to specify
|
|
where the mixer is to be found. For example, if the mixer is associated with a card,
|
|
as is often the case, specify the card, e.g. <b>hw:0</b>.
|
|
If (unusually) the mixer is associated with a specific device on a card,
|
|
specify the device, e.g. <b>hw:0,1</b>.
|
|
The default is the device named in the <b>-d</b> option,
|
|
if given, or the device named <b>default</b>.
|
|
</p>
|
|
|
|
|
|
|
|
<p><b>-t </b><em>devicetype</em></p>
|
|
|
|
<p>
|
|
This option is deprecated and is ignored. For your information, its functionality has
|
|
been automatically incorporated in the -c option
|
|
-- if you specify a mixer name with the -c option, it is assumed that the mixer is
|
|
implemented in hardware.
|
|
</p>
|
|
|
|
|
|
|
|
<h2>Examples</h2>
|
|
|
|
<p>Here is a slightly contrived example:</p>
|
|
shairport-sync <b>-d</b>
|
|
<b>-a "Joe's Stereo"</b>
|
|
<b>-S soxr</b>
|
|
<b>--</b>
|
|
<b>-d hw:1,0</b>
|
|
<b>-m hw:1</b>
|
|
<b>-c PCM</b>
|
|
<br>
|
|
|
|
<p>The program will run in daemon mode ( <b>-d</b> ), will be visible as
|
|
"Joe's Stereo" ( <b>-a "Joe's Stereo"</b> ) and will use the SoX Resampler
|
|
Library-based stuffing ( <b>-S soxr</b> ).
|
|
The audio backend options following the <b>--</b> separator specify
|
|
that the audio will be output on output 0 of soundcard 1
|
|
( <b>-d hw:1,0</b> ) and will take advantage of the same sound card's mixer
|
|
( <b>-m hw:1</b> ) using the level control named "PCM" ( <b>-c "PCM"</b> ).
|
|
</p>
|
|
<p>The example above is slightly contrived in order to show the use of the <b>-m</b>
|
|
option. Typically, output 0 is the default output of a card, so the output device could
|
|
be written <b>-d hw:1</b> and then the mixer option would be unnecessary, giving the following, simpler, command:</p>
|
|
shairport-sync <b>-d</b>
|
|
<b>-a "Joe's Stereo"</b>
|
|
<b>-S soxr</b>
|
|
<b>--</b>
|
|
<b>-d hw:1</b>
|
|
<b>-c PCM</b>
|
|
<br>
|
|
|
|
|
|
|
|
|
|
|
|
<h2>Credits</h2>
|
|
|
|
<p>Mike Brady developed shairport-sync from the original Shairport by James Laird.</p>
|
|
<p>shairport-sync can be found at
|
|
<a href = "https://github.com/mikebrady/shairport-sync.">https://github.com/mikebrady/shairport-sync.</a></p>
|
|
<p>Shairport can be found at
|
|
<a href = "https://github.com/abrasive/shairport.">https://github.com/abrasive/shairport.</a></p>
|
|
|
|
|
|
|
|
<h2>Comments</h2>
|
|
|
|
<p>This man page was written using <a href="http://masqmail.cx/xml2man/">xml2man</a> by Oliver Kurth.</p>
|
|
|
|
|
|
|
|
</td></tr></table></center>
|
|
</body>
|