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Options
Type | Short | Long | Description | Hint |
---|---|---|---|---|
Option | h | help | Print a list of options and flags. | |
Option | c | cache | Path to a directory where files will be cached. | PATH |
Option | system-cache | Path to a directory where system files (credentials, volume) will be cached. May be different from the cache option value. | PATH | |
Option | cache-size-limit | Limits the size of the cache for audio files. It's possible to use suffixes like K , M or G . |
SIZE | |
Flag | disable-audio-cache | Disable caching of the audio data. | ||
Option | n | name | Device name. | NAME |
Option | device-type | Displayed device type: computer , tablet , smartphone , speaker , tv , avr (Audio/Video Receiver), stb (Set-Top Box), audiodongle , gameconsole , castaudio , castvideo , automobile , smartwatch , chromebook , carthing , homething . Defaults to speaker . |
TYPE | |
Option | b | bitrate | Bitrate (kbps): 96 , 160 , 320 . Defaults to 160 . |
BITRATE |
Option | onevent | The path to a script that gets run when one of librespot's events is triggered. | PROGRAM | |
Flag | emit-sink-events | Run PROGRAM set by --onevent before sink is opened and after it is closed. |
||
Option | V | version | Display librespot version string. | |
Flag | v | verbose | Enable verbose output | PROGRAM |
Option | u | username | Username used to sign in with. | USERNAME |
Option | p | password | Password used to sign in with. | PASSWORD |
Option | proxy | Use a proxy for HTTP requests. Proxy should be an HTTP proxy in the form http://ip:port , and can also be passed using the all-lowercase http_proxy environment variable. |
URL | |
Option | ap-port | Connect to an AP with a specified port. If no AP with that port is present a fallback AP will be used. Available ports are usually 80 , 443 and 4070 . |
PORT | |
Flag | disable-discovery | Disable zeroconf discovery mode. | ||
Option | backend | Audio backend to use. Use '?' to list options | NAME | |
Option | device | Audio device to use. Use '?' to list options if using alsa, portaudio or rodio. Defaults to the backend's default. | NAME | |
Option | format | Output format: F64 , F32 , S32 , S24 , S24_3 , S16 . Defaults to S16 . |
FORMAT | |
Option | dither | Dither algorithm: none , gpdf , tpdf , tpdf_hp . Defaults to tpdf for formats S16 , S24 , S24_3 and none for other formats. |
TYPE | |
Option | m | mixer | Mixer to use: softvol , alsa . Defaults to softvol . |
MIXER |
Option | alsa-mixer-control |
alsa mixer control, e.g. PCM , Master or similar. Defaults to PCM . |
NAME | |
Option | alsa-mixer-device |
alsa mixer device, e.g hw:0 or similar from aplay -l . Defaults to --device if specified, default otherwise. |
DEVICE | |
Option | alsa-mixer-index |
alsa mixer index, Index of the cards mixer. Defaults to 0. |
NUMBER | |
Option | initial-volume | Initial volume in % from 0-100. Default for softvol: 50 . For the alsa mixer: the current volume. |
VOLUME | |
Option | zeroconf-port | The port the internal server advertises over zeroconf: 1 -65535 . Ports <= 1024 may require root privileges. |
PORT | |
Flag | enable-volume-normalisation | Enables volume normalisation for librespot | ||
Option | normalisation-method | Specify the normalisation method to use: basic , dynamic . Defaults to dynamic . |
METHOD | |
Option | normalisation-gain-type | Specify the normalisation gain type to use: track , album , auto . Defaults to auto . |
TYPE | |
Option | normalisation-pregain | Pregain (dB) applied by the normalisation. Defaults to 0 . |
PREGAIN | |
Option | normalisation-threshold | Threshold (dBFS) to prevent clipping. Defaults to -1.0 . |
THRESHOLD | |
Option | normalisation-attack | Attack time (ms) in which the dynamic limiter is reducing gain. Defaults to 5 . |
TIME | |
Option | normalisation-release | Release or decay time (ms) in which the dynamic limiter is restoring gain. Defaults to 100 . |
TIME | |
Option | normalisation-knee | Knee steepness of the dynamic limiter. Default is 1.0 . |
KNEE | |
Option | volume-ctrl | Volume control type cubic , fixed , linear , log . Defaults to log . |
VOLUME_CTRL | |
Option | volume-range | Range of the volume control (dB). Default for softvol: 60 . For the alsa mixer: what the control supports. |
RANGE | |
Flag | autoplay | Autoplay similar songs when your music ends. | ||
Flag | disable-gapless | Disables gapless playback by forcing the sink to close between tracks. | ||
Flag | passthrough | Pass a raw stream to the output. Only works with the pipe and subprocess backends. |
librespot
supports ReplayGain volume normalisation, with the ReplayGain values provided by Spotify in the Ogg streams. As of librespot
0.2.0, there are two types of volume normalisation methods available:
The volume is increased or decreased as per the average ReplayGain of that track or its album. If that would result in peaks over a certain threshold (hard-coded at 0 dBFS for librespot
up to 0.1.6; -1 dBFS and configurable as of librespot
0.2.0), then the volume increase is limited so that the peak is exactly 0 dBFS. This gain is fixed for the entire duration of the track.
This is the only limiter available in librespot
up to 0.1.6.
(as of librespot
0.2.0)
Again the volume is increased or decreased as per the average ReplayGain of that track or its album. However, if this now results in peaks over the threshold (-2 dBFS by default), the gain is dynamically reduced for the duration of that peak, then recovered to the original target gain. This length of the attack and release for this reduction and recovery from zero to full effect by default mimic the Spotify client, and are configurable.
During the attack and release period, the rate of change from zero to full effect (the "knee") has a configurable steepness. By default this is 1.0, which means a linear slope. Values above 1.0 yield softer knees with a more gentle start and end but steeper rate of change mid-way. Values below 1.0 start and stop more sharply, and are flatter in between. Values of 0.0 and below first give an impulse response, then invert the limiter, and should not be used.
The equivalent librespot
options to match the volume normalisation settings in official Spotify clients are:
Loud
--enable-volume-normalisation --normalisation-pregain 3
Normal (Default)
--enable-volume-normalisation --normalisation-pregain 0
Quiet
--enable-volume-normalisation --normalisation-pregain -9
librespot
up to 0.1.6 always outputs 16-bit samples, except for JACK Audio where it converts to 32-bit output after volume control.
As of librespot
0.2.0, the audio output is still 16-bit by default, but can be configured to output 32-bit floating point (F32
), 32-bit integer (S32
), 24-bit PCM in a 32-bit word (S24
) or 24-bit integer packed as three bytes (S24_3
). Software volume control and normalisation is done before sample conversion, so that there is no loss of dynamic range.
By default, volume control will be done using the software volume mixer.
As of librespot 0.3.0, softvol
and the rest of the audio sample pipeline completely works in 64-bit floating point. While some audiophiles may prefer to do volume control in hardware, a 64-bit pipeline is completely transparent and quite likely better than the 32-bit signed integer many hardware DACs work in.
There may be other valid reasons to use the alsa
mixer, however:
-
Keeping the current playback volume instead of overwriting it with
initial-volume
(this is especially useful when you are switching back and forth librespot and other audio renderers). -
Latching off the mute / unmute switch; librespot will toggle mute on hardware devices that support it when volume is dialed back to 0.
For the purists, you can use --mixer softvol --volume-ctrl fixed --initial-volume 100
to completely bypass volume control.
As of librespot
0.3.0, the cubic volume control is available on both the softvol
and alsa
mixers (before 0.3.0, only on alsa
). Cubic is like log, but has a bit more fine-grained control in the upper volume range. The specifics are documented here.
Librespot
0.3.0 also fixed the way --mixer alsa
handles linear
and log
volume controls. Before 0.3.0, you have to set --volume-ctrl linear
to get a log control; you can't get a true linear control and doing --volume-ctrl log
doesn't work correctly. This is no longer the case from 0.3.0 onwards.
Note that just setting --backend alsa
still uses librespot
softvol
. You also need to set --mixer alsa
if you want to have volume control done by Alsa or in hardware. Note that softvol
is recommended unless you have specific requirements. As of librespot
0.3.0, softvol
works in 64-bit floating point which is better than most hardware implementations, even if you have a 32-bit DAC.
(as of librespot
0.3.0)
librespot
supports dithering to lower the requantisation errors, that is caused by converting digital (ones and zeroes) to analog audio (continuous waveforms). Doing so lowers distortion and improves audio quality.
-
On
S24
,S24_3
andS24
, the default is to use triangular dithering. Depending on personal preference you may use Gaussian dithering instead; it's not as good objectively, but it may be preferred subjectively if you are looking for a more "analog" sound akin to tape hiss. -
Advanced users who know that they have a DAC without noise shaping have a third option: high-passed dithering, which is like triangular dithering except that it moves dithering noise up in frequency where it is less audible. Note: 99% of DACs are of delta-sigma design with noise shaping, so unless you have a multibit / R2R DAC, or otherwise know what you are doing, this is not for you.
-
Don't dither or shape noise on
S32
orF32
. OnF32
it's not supported anyway (there are no integer conversions and so no rounding errors) and on S32 the noise level is so far down that it is simply inaudible even after volume normalisation and control.