%

(string, [(string*string)]) -> string

(pattern % [...,(k,v),...]) replaces in pattern occurences of: - '$(k)' into "v"; - '$(if $(k2),"a","b")' into "a" if k2 is found in the list, "b" otherwise.

^

(string, string) -> string

Concatenate strings.

add

(?id:string, ?normalize:bool, ?weights:[int], [source]) -> source

Add sources, with normalization

[source] (unlabeled)

string id ""

Force the value of the source ID

bool normalize true

[int] weights [ ]

Relative weight of the sources in the sum. The empty list stands for the homogeneous distribution.

add_protocol

(string, ((string, float) -> [string])) -> unit

Register a new protocol.

and

(bool, bool) -> bool

Return the conjunction of its arguments

append

(?id:string, ?merge:bool, source, (([(string*string)]) -> source)) -> source

Append an extra track to every track.Set the metadata 'liq_append' to 'false' to inhibit appending on one track.

([(string*string)]) -> source (unlabeled)

Given the metadata, build the source producing the track to append. This source is allowed to fail (produce nothing) if no relevant track is to be appended.

source (unlabeled)

string id ""

Force the value of the source ID

bool merge false

Merge the track with its appended track.

assoc

(string, [(string*string)]) -> string

assoc k [...,(k,v),...] = v

blank

(?id:string, ?duration:float) -> source

This source is not very noisy :)

float duration 0.

Duration of blank tracks, default means forever.

string id ""

Force the value of the source ID

change_volume

(?id:string, float, source) -> source

Scales the amplitude of the signal

source (unlabeled)

float (unlabeled)

multiplicative factor

string id ""

Force the value of the source ID

cross

(?id:string, ?duration:float, ?inhibit:float, ?minimum:float, ((source, source) -> source), source) -> source

Generic cross operator, allowing the composition of the N last seconds of a track with the beginning of the next track.

source (unlabeled)

(source, source) -> source (unlabeled)

Composition of an end of track and the next track.

float duration 5.

Duration in seconds of the crossed end of track. This value can be set on a per-file basis using the metadata field 'liq_start_next' (float in seconds).

string id ""

Force the value of the source ID

float inhibit -1.

Minimum delay between two transitions. It is useful in order to avoid that a transition is triggered on top of another when an end-of-track occurs in the first one. Negative values mean 'same as duration'.

float minimum -1.

Minimum duration (in sec.) for a cross: If the track ends without any warning (e.g. in case of skip) there may not be enough data for a decent composition. Set to 0. to avoid having transitions after skips, or more to avoid transitions on short tracks. With the negative default, transitions always occur.

delay

(?id:string, float, source) -> source

Prevents the child from being ready again too fast after a end of track

source (unlabeled)

float (unlabeled)

The source won't be ready less than this amount of seconds after any end of track

string id ""

Force the value of the source ID

fade.final

(?id:string, ?duration:float, source) -> source

Fade a stream to silence.

source (unlabeled)

float duration 3.

string id ""

Force the value of the source ID

fade.in

(?id:string, ?duration:float, source) -> source

Fade the beginning of tracks. Metadata 'liq_fade_in' can be used to set the duration for a specific track (float in seconds).

source (unlabeled)

float duration 3.

string id ""

Force the value of the source ID

fade.initial

(?id:string, ?duration:float, source) -> source

Fade the beginning of a stream.

source (unlabeled)

float duration 3.

string id ""

Force the value of the source ID

fade.out

(?id:string, ?duration:float, source) -> source

Fade the end of tracks. Metadata 'liq_fade_out' can be used to set the duration for a specific track (float in seconds).

source (unlabeled)

float duration 3.

string id ""

Force the value of the source ID

fallback

(?id:string, ?track_sensitive:bool, ?before:float, ?transitions:[(source, source) -> source], [source]) -> source

At the beginning of each track, select the first ready child.

[source] (unlabeled)

Select the first ready source in this list.

float before 0.

EXPERIMENTAL: for track_sensitive switches, trigger transitions before the end of track.

string id ""

Force the value of the source ID

bool track_sensitive true

Re-select only on end of tracks

[(source, source) -> source] transitions [ ]

Transition functions, padded with (fun (x,y) -> y) functions.

filter

(?id:string, ~freq:int, ~q:float, ~mode:string, source) -> source

Perform several kinds of filtering on the signal

source (unlabeled)

int freq

string id ""

Force the value of the source ID

string mode

low|high|band|notch

float q

get_process_lines

(string) -> [string]

Perform a shell call and return the list of its output lines.

get_process_output

(string) -> string

Perform a shell call and return its output.

input.http

(?id:string, ?autostart:bool, string) -> source

Forwards the given ogg/vorbis http stream. The relay can be paused/resumed using the start/stop telnet commands.

string (unlabeled)

URL of an http ogg stream (default port is 8000).

bool autostart true

Initially start relaying or not.

string id ""

Force the value of the source ID

input.http.mp3

(?id:string, string, ?autostart:bool, ?samplefreq:int) -> source

Forwards the given MP3 http stream. The relay can be paused/resumed using the start/stop telnet commands.

string (unlabeled)

URL of an http mp3 stream (default port is 8000).

bool autostart true

Initially start relaying or not.

string id ""

Force the value of the source ID

int samplefreq 44100

Samplefreq of the input stream.

mix

(?id:string, [source]) -> source

Mixing table controllable via the telnet interface.

[source] (unlabeled)

string id ""

Force the value of the source ID

on_blank

(?id:string, (() -> unit), ?threshold:float, ?length:float, source) -> source

Calls a given handler when detecting a blank

source (unlabeled)

() -> unit (unlabeled)

string id ""

Force the value of the source ID

float length 20.

Maximum silence length allowed.

float threshold 100.

Intensity threshold under which the stream is considered to be blank.

on_metadata

(?id:string, (([(string*string)]) -> unit), source) -> source

Call a given handler on metadata packets.

source (unlabeled)

([(string*string)]) -> unit (unlabeled)

Function called on every metadata packet in the stream. It should be fast because it is ran in the main thread.

string id ""

Force the value of the source ID

or

(bool, bool) -> bool

Return the disjunction of its arguments

output.ao

(?id:string, ?start:bool, ?driver:string, ?options:[(string*string)], source) -> source

Output stream to local sound card using libao.

source (unlabeled)

string driver ""

libao driver to use

string id ""

Force the value of the source ID

[(string*string)] options [ ]

List of parameters, depends on driver

bool start true

Start output on operator initialization.

output.dummy

(?id:string, source) -> source

Dummy output for debugging purposes.

source (unlabeled)

string id ""

Force the value of the source ID

output.icecast

(?id:string, ?start:bool, ?host:string, ?port:int, ?user:string, ?password:string, ?genre:string, ?url:string, ?description:string, ?public:bool, ?multicast_ip:string, ?mount:string, ?name:string, ?bitrate:int, ?quality:float, ?freq:int, ?stereo:bool, source) -> source

Send a Vorbis stream to an icecast-compatible server.

source (unlabeled)

int bitrate -1

string description "OCaml Radio!"

int freq 44100

string genre "Misc"

string host "localhost"

string id ""

Force the value of the source ID

string mount "Use [name].ogg"

string multicast_ip "no_multicast"

string name "Use [mount]"

string password "hackme"

int port 8000

bool public true

float quality 0.5

bool start true

Start output threads on operator initialization.

bool stereo true

string url "http://savonet.sf.net"

string user "source"

output.ogg

(?id:string, ?start:bool, ?quality:float, ?bitrate:int, ?freq:int, ?stereo:bool, string, source) -> source

Output the source's stream as an OGG file.

source (unlabeled)

string (unlabeled)

Filename where to output the OGG stream.

int bitrate -1

int freq 44100

string id ""

Force the value of the source ID

float quality 0.5

bool start true

Start output threads on operator initialization.

bool stereo true

output.wav

(?id:string, ?start:bool, string, source) -> source

Output the source's stream to a WAV file.

source (unlabeled)

string (unlabeled)

string id ""

Force the value of the source ID

bool start true

pipe

(?id:string, string, source) -> source

Filter data through an external process. The process should read raw CD format on stdin and write the same on stdout. The command should output one frame for every input frame, and flush its output. Otherwise, liquidsoap will block.

source (unlabeled)

string (unlabeled)

string id ""

Force the value of the source ID

playlist

(?id:string, ?length:float, ?default_duration:float, ?timeout:float, ?mode:string, ?reload:int, ?reload_mode:string, string) -> source

Loop on a playlist of URIs.

string (unlabeled)

URI where to find the playlist

float default_duration 30.

When unknown, assume this duration (in sec.) for files.

string id ""

Force the value of the source ID

float length 60.

How much audio (in sec.) should be downloaded in advance.

string mode "randomize"

normal|random|randomize

int reload 0

Amount of time (in seconds or rounds) before which the playlist is reloaded; 0 means never.

string reload_mode "seconds"

rounds|seconds: unit of the 'reload' parameter

float timeout 20.

Timeout (in sec.) for a single download.

playlist.safe

(?id:string, ?mode:string, ?reload:int, ?reload_mode:string, string) -> source

Loop on a playlist of local files, and never fail. In order to do so, it has to check every file at the loading, so the streamer startup may take a few seconds. To avoid this, use a standard playlist, and put only a few local files in a default safe_playlist in order to ensure the liveness of the streamer.

string (unlabeled)

URI where to find the playlist

string id ""

Force the value of the source ID

string mode "randomize"

normal|random|randomize

int reload 0

Amount of time (in seconds or rounds) before which the playlist is reloaded; 0 means never.

string reload_mode "seconds"

rounds|seconds: unit of the 'reload' parameter

prepend

(?id:string, ?merge:bool, source, (([(string*string)]) -> source)) -> source

Prepend an extra track before every track. Set the metadata 'liq_prepend' to 'false' to inhibit prepending on one track.

([(string*string)]) -> source (unlabeled)

Given the metadata, build the source producing the track to prepend. This source is allowed to fail (produce nothing) if no relevant track is to be appended. However, success must be immediate.

source (unlabeled)

string id ""

Force the value of the source ID

bool merge false

Merge the track with its appended track.

quote

(string) -> string

Escape shell metacharacters.

random

(?id:string, ?track_sensitive:bool, ?before:float, ?transitions:[(source, source) -> source], ?weights:[int], ?strict:bool, [source]) -> source

At the beginning of every track, select a random ready child.

[source] (unlabeled)

float before 0.

EXPERIMENTAL: for track_sensitive switches, trigger transitions before the end of track.

string id ""

Force the value of the source ID

bool strict false

Do not use random but cycle over the uniform distribution.

bool track_sensitive true

Re-select only on end of tracks

[(source, source) -> source] transitions [ ]

Transition functions, padded with (fun (x,y) -> y) functions.

[int] weights [ ]

Weights of the children in the choice.

request

(?indicators:[string], string) -> request

Create a request.

request.dynamic

(?id:string, (() -> request), ?length:float, ?default_duration:float, ?timeout:float) -> source

Play request dynamically created by a given function.

() -> request (unlabeled)

A function generating requests: an initial URI (possibly fake) together with an initial list of alternative indicators

float default_duration 30.

When unknown, assume this duration (in sec.) for files.

string id ""

Force the value of the source ID

float length 60.

How much audio (in sec.) should be downloaded in advance.

float timeout 20.

Timeout (in sec.) for a single download.

request.equeue

(?id:string, ?length:float, ?default_duration:float, ?timeout:float) -> source

Receive URIs from users, and play them. Insertion and deletion possible at any position.

float default_duration 30.

When unknown, assume this duration (in sec.) for files.

string id ""

Force the value of the source ID

float length 60.

How much audio (in sec.) should be downloaded in advance.

float timeout 20.

Timeout (in sec.) for a single download.

request.queue

(?id:string, ?length:float, ?default_duration:float, ?timeout:float) -> source

Receive URIs from users, and play them.

float default_duration 30.

When unknown, assume this duration (in sec.) for files.

string id ""

Force the value of the source ID

float length 60.

How much audio (in sec.) should be downloaded in advance.

float timeout 20.

Timeout (in sec.) for a single download.

rewrite_metadata

(?id:string, [(string*string)], source) -> source

Rewrite metadata on the fly.

source (unlabeled)

[(string*string)] (unlabeled)

List of (target,value) rewriting rules.

string id ""

Force the value of the source ID

sequence

(?id:string, ?merge:bool, [source]) -> source

Play only one track of every successive source, except for the last one which is played as much as available.

[source] (unlabeled)

string id ""

Force the value of the source ID

bool merge false

sine

(?id:string, ?duration:float, int) -> source

Plays a boring sine...

int (unlabeled)

Frequency of the sine

float duration 0.

string id ""

Force the value of the source ID

single

(?id:string, string, ?length:float, ?default_duration:float, ?timeout:float) -> source

Loop on a request. It never fails if the request is static, meaning that it can be fetched once. Typically, http, ftp, say requests are static, and time is not.

string (unlabeled)

URI where to find the file

float default_duration 30.

When unknown, assume this duration (in sec.) for files.

string id ""

Force the value of the source ID

float length 60.

How much audio (in sec.) should be downloaded in advance.

float timeout 20.

Timeout (in sec.) for a single download.

skip_blank

(?id:string, ?threshold:float, ?length:float, source) -> source

Skip track when detecting a blank

source (unlabeled)

string id ""

Force the value of the source ID

float length 20.

Maximum silence length allowed.

float threshold 100.

Intensity threshold under which the stream is considered to be blank.

store_metadata

(?id:string, ?size:int, source) -> source

Keep track of the last N metadata packets in the stream, and make the history available via a server command.

source (unlabeled)

string id ""

Force the value of the source ID

int size 10

Size of the history

strip_blank

(?id:string, ?threshold:float, ?length:float, source) -> source

Strip blanks

source (unlabeled)

string id ""

Force the value of the source ID

float length 20.

Maximum silence length allowed.

float threshold 100.

Intensity threshold under which the stream is considered to be blank.

switch

(?id:string, ?track_sensitive:bool, ?before:float, ?transitions:[(source, source) -> source], ?strict:bool, ?single:[bool], [((() -> bool)*source)]) -> source

At the beginning of a track, select the first source Si such than the temporal predicate Ii is true.

[((() -> bool)*source)] (unlabeled)

Sources Si with the interval Ii when they should be played.

float before 0.

EXPERIMENTAL: for track_sensitive switches, trigger transitions before the end of track.

string id ""

Force the value of the source ID

[bool] single [ ]

Forbid the selection of a branch for two tracks in a row. The empty list stands for [false,...,false].

bool strict false

Unset the operator's ready flag as soon as there is no valid interval, possibly interrupting ongoing tracks.

bool track_sensitive true

Re-select only on end of tracks

[(source, source) -> source] transitions [ ]

Transition functions, padded with (fun (x,y) -> y) functions.

system

(string) -> unit

Shell command call.

time_in_mod

(int, int, int) -> bool

INTERNAL: time_in_mod(a,b,c) checks that the unix time T satisfies a <= T mod c < b