sintonia/python_apps/pypo/liquidsoap/library/utils.liq

730 lines
22 KiB
Plaintext
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

# Turn a source into an infaillible source.
# by adding blank when the source is not available.
# @param s the source to turn infaillible
# @category Source / Track Processing
def mksafe(~id="mksafe",s)
fallback(id=id,track_sensitive=false,[s,blank(id="safe_blank")])
end
# Alias for the <code>l[k]</code> notation.
# @category List
# @param a Key to look for
# @param l List of pairs (key,value)
def list.assoc(a,l)
l[a]
end
# list.mem_assoc(key,l) returns true if l contains a pair
# (key,value)
# @category List
# @param a Key to look for
# @param l List of pairs (key,value)
def list.mem_assoc(a,l)
def f(cur, el) =
if not cur then
fst(el) == a
else
cur
end
end
list.fold(f, false, l)
end
# Remove a pair from an associative list
# @category List
# @param a Key of pair to be removed
# @param l List of pairs (key,value)
def list.remove_assoc(a,l)
list.remove((a,list.assoc(a,l)),l)
end
# Rewrite metadata on the fly using a list of (target,rules).
# @category Source / Track Processing
# @param l \
# List of (target,value) rewriting rules.
# @param ~insert_missing \
# Treat track beginnings without metadata as having empty ones. \
# The operational order is: \
# create empty if needed, map and strip if enabled.
# @param ~update \
# Only update metadata. \
# If false, only returned values will be set as metadata.
# @param ~strip \
# Completly remove empty metadata. \
# Operates on both empty values and empty metadata chunk.
def rewrite_metadata(l,~insert_missing=true,
~update=true,~strip=false,
s)
# We don't need to return all values, since
# map_metadata only update returned values.
# So, we simply apply all rewrite rules !
def map(m)
def apply(x)
label = fst(x)
value = snd(x)
(label,value % m)
end
list.map(apply,l)
end
map_metadata(map,insert_missing=insert_missing,
update=update,strip=strip,s)
end
# Add a skip function to a source
# when it does not have one
# by default
# @category Interaction
# @param s The source to attach the command to.
def add_skip_command(s) =
# A command to skip
def skip(_) =
source.skip(s)
"Done!"
end
# Register the command:
server.register(namespace="#{source.id(s)}",
usage="skip",
description="Skip the current song.",
"skip",skip)
end
# Removes all metadata coming from a source
# @category Source / Track Processing
def drop_metadata(s)
map_metadata(fun(_)->[],update=false,strip=true,insert_missing=false,s)
end
# Merge all tracks from a source, provided that it does not fail
# @category Source / Track Processing
def merge_tracks(s)
sequence(merge=true,[s])
end
# Default inputs and outpus
#
# They are called "prefered" but it's not a user preference,
# just a view of what's generally preferable among the available
# modules.
# It is important that input and output preferences are in the
# same order: the chosen I/O should work in the same clock, we don't
# want an ALSA input and OSS output. The only exception is AO:
# it is the default output after dummy, so the input will be a dummy
# when AO is used for output.
output.prefered=output.dummy
%ifdef output.ao
output.prefered=output.ao
%endif
%ifdef output.alsa
output.prefered=output.alsa
%endif
%ifdef output.oss
output.prefered=output.oss
%endif
%ifdef output.portaudio
output.prefered = output.portaudio
%endif
%ifdef output.pulseaudio
output.prefered=output.pulseaudio
%endif
# Output to local audio card using the first available driver in
# pulseaudio, portaudio, oss, alsa, ao, dummy.
# @category Source / Output
def output.prefered(~id="",~fallible=false,
~on_start={()},~on_stop={()},~start=true,s)
output.prefered(id=id,fallible=fallible,
start=start,on_start=on_start,on_stop=on_stop,
s)
end
def in(~id="",~start=true,~on_start={()},~on_stop={()},~fallible=false)
blank(id=id)
end
%ifdef input.alsa
in = input.alsa
%endif
%ifdef input.oss
in = input.oss
%endif
%ifdef input.portaudio
in = input.portaudio
%endif
%ifdef input.pulseaudio
in = input.pulseaudio
%endif
# Create a source from the first available input driver in
# pulseaudio, portaudio, oss, alsa, blank.
# @category Source / Input
def in(~id="",~start=true,~on_start={()},~on_stop={()},~fallible=false)
in(id=id,start=start,on_start=on_start,on_stop=on_stop,fallible=fallible)
end
# Output a stream using the 'output.prefered' operator. The input source does
# not need to be infallible, blank will just be played during failures.
# @param s the source to output
# @category Source / Output
def out(s)
output.prefered(mksafe(s))
end
# Special track insensitive fallback that always skips current song before switching.
# @category Source / Track Processing
# @param ~input The input source
# @param f The fallback source
def fallback.skip(~input,f)
def transition(a,b) =
source.skip(a)
# This eats the last remaining frame from a
sequence([a,b])
end
fallback(track_sensitive=false,transitions=[transition,transition],[input,f])
end
# Compress and normalize, producing a more uniform and "full" sound.
# @category Source / Sound Processing
# @param s The input source.
def nrj(s)
compress(threshold=-15.,ratio=3.,gain=3.,normalize(s))
end
# Multiband-compression.
# @category Source / Sound Processing
# @param s The input source.
def sky(s)
# 3-band crossover
low = filter.iir.eq.low(frequency = 168.)
mh = filter.iir.eq.high(frequency = 100.)
mid = filter.iir.eq.low(frequency = 1800.)
high = filter.iir.eq.high(frequency = 1366.)
# Add back
add(normalize = false,
[ compress(attack = 100., release = 200., threshold = -20.,
ratio = 6., gain = 6.7, knee = 0.3,
low(s)),
compress(attack = 100., release = 200., threshold = -20.,
ratio = 6., gain = 6.7, knee = 0.3,
mid(mh(s))),
compress(attack = 100., release = 200., threshold = -20.,
ratio = 6., gain = 6.7, knee = 0.3,
high(s))
])
end
# Simple crossfade.
# @category Source / Track Processing
# @param ~start_next Duration in seconds of the crossed end of track.
# @param ~fade_in Duration of the fade in for next track.
# @param ~fade_out Duration of the fade out for previous track.
# @param ~conservative Always prepare for a premature end-of-track.
# @param s The source to use.
def crossfade(~id="",~conservative=true,
~start_next=5.,~fade_in=3.,~fade_out=3.,
s)
s = fade.in(duration=fade_in,s)
s = fade.out(duration=fade_out,s)
fader = fun (a,b) -> add(normalize=false,[b,a])
cross(id=id,conservative=conservative,duration=start_next,fader,s)
end
# Append speech-synthesized tracks reading the metadata.
# @category Source / Track Processing
# @param ~pattern Pattern to use
# @param s The source to use
def say_metadata
p = 'say:$(if $(artist),"It was $(artist)$(if $(title),\", $(title)\").")'
fun (s,~pattern=p) ->
append(s,fun (m) -> request.queue(queue=[request.create(pattern % m)],
interactive=false))
end
%ifdef soundtouch
# Increases the pitch, making voices sound like on helium.
# @category Source / Sound Processing
# @param s The input source.
def helium(s)
soundtouch(pitch=1.5,s)
end
%endif
# Return true if process exited with 0 code. Command should return quickly.
# @category System
# @param command Command to test
def test_process(command)
lines =
get_process_lines("(" ^ command ^ " >/dev/null 2>&1 && echo 0) || echo 1")
if list.length(lines) == 0 then
false
else
"0" == list.hd(lines)
end
end
# Split an url of the form foo?arg=bar&arg2=bar2
# into ("foo",[("arg","bar"),("arg2","bar2")]).
# @category String
# @param uri Url to split
def url.split(uri) =
ret = string.extract(pattern="([^\?]*)\?(.*)",uri)
args = ret["2"]
if args != "" then
l = string.split(separator="&",args)
def f(x) =
ret = string.split(separator="=",x)
(url.decode(list.nth(ret,0)),
url.decode(list.nth(ret,1)))
end
l = list.map(f,l)
(ret["1"],l)
else
(uri,[])
end
end
# Register a server/telnet command to update a source's metadata. Returns
# a new source, which will receive the updated metadata. The command has
# the following format: insert key1="val1",key2="val2",...
# @category Source / Track Processing
# @param ~id Force the value of the source ID.
def server.insert_metadata(~id="",s) =
x = insert_metadata(id=id,s)
insert = fst(x)
s = snd(x)
def insert(s) =
l = string.split(separator='([^=]+\s*=\s*"(\\"|[^"])*")\s*,\s*',s)
def f(l,x) =
sub = fun (s) -> string.replace(pattern='\\"',fun (_) -> '"',s)
if x != "" then
ret = string.extract(pattern='([^=]+)\s*=\s*"((?:\\"|[^"])*)"',x)
if ret["1"] != "" then
list.append(l,[(ret["1"],
sub(ret["2"]))])
else
l
end
else
l
end
end
meta = list.fold(f,[],l)
if meta != [] then
insert(meta)
"Done"
else
"Syntax error or no metadata given. \
Use key1=\"val1\",key2=\"val2\",.."
end
end
id = source.id(s)
server.register(namespace="#{id}",
description="Insert a metadata chunk.",
usage="insert key1=\"val1\",key2=\"val2\",..",
"insert",insert)
s
end
# Register a command that outputs the RMS of the returned source.
# @category Source / Visualization
# @param ~id Force the value of the source ID.
def server.rms(~id="",s) =
x = rms(id=id,s)
rms = fst(x)
s = snd(x)
id = source.id(s)
def rms(_) =
rms = rms()
"#{rms}"
end
server.register(namespace="#{id}",
description="Return the current RMS of the source.",
usage="rms",
"rms",rms)
s
end
# Read some value from standard input (console).
# @category System
# @param ~hide Hide typed characters (for passwords).
def read(~hide=false)
if hide then
system("stty -echo")
end
s = list.hd(get_process_lines("read BLA && echo $BLA"))
if hide then
system("stty echo")
end
print("")
s
end
# Dummy implementation of file.mime
# @category System
def file.mime_default(_)
""
end
%ifdef file.mime
# Alias of file.mime (because it is available)
# @category System
def file.mime_default(file)
file.mime(file)
end
%endif
# Generic mime test. First try to use file.mime if it exist.
# Otherwise try to get the value using the file binary.
# Returns "" (empty string) if no value can be find.
# @category System
# @param file The file to test
def get_mime(file) =
def file_method(file) =
if test_process("which file") then
list.hd(get_process_lines("file -b --mime-type \
#{quote(file)}"))
else
""
end
end
# First try mime method
ret = file.mime_default(file)
if ret != "" then
ret
else
# Now try file method
file_method(file)
end
end
# Remove low frequencies often produced by microphones.
# @category Source / Sound Processing
# @param s The input source.
def mic_filter(s)
filter(freq=200.,q=1.,mode="high",s)
end
# Creates a source that fails to produce anything.
# @category Source / Input
def fail(~id="")
fallback(id=id,[])
end
# Creates a source that plays only one track of the input source.
# @category Source / Track Processing
# @param s The input source.
def once(s)
sequence([s,fail()])
end
# Crossfade between tracks, taking the respective volume levels into account in
# the choice of the transition.
# @category Source / Track Processing
# @param ~start_next Crossing duration, if any.
# @param ~fade_in Fade-in duration, if any.
# @param ~fade_out Fade-out duration, if any.
# @param ~width Width of the volume analysis window.
# @param ~conservative Always prepare for a premature end-of-track.
# @param ~default Transition used when no rule applies \
# (default: sequence).
# @param ~high Value, in dB, for loud sound level.
# @param ~medium Value, in dB, for medium sound level.
# @param ~margin Margin to detect sources that have too different \
# sound level for crossing.
# @param s The input source.
def smart_crossfade (~start_next=5.,~fade_in=3.,~fade_out=3.,
~default=(fun (a,b) -> sequence([a, b])),
~high=-15., ~medium=-32., ~margin=4.,
~width=2.,~conservative=true,s)
fade.out = fade.out(type="sin",duration=fade_out)
fade.in = fade.in(type="sin",duration=fade_in)
add = fun (a,b) -> add(normalize=false,[b, a])
log = log(label="smart_crossfade")
def transition(a,b,ma,mb,sa,sb)
list.iter(fun(x)-> log(level=4,"Before: #{x}"),ma)
list.iter(fun(x)-> log(level=4,"After : #{x}"),mb)
if
# If A and B are not too loud and close, fully cross-fade them.
a <= medium and b <= medium and abs(a - b) <= margin
then
log("Old <= medium, new <= medium and |old-new| <= margin.")
log("Old and new source are not too loud and close.")
log("Transition: crossed, fade-in, fade-out.")
add(fade.out(sa),fade.in(sb))
elsif
# If B is significantly louder than A, only fade-out A.
# We don't want to fade almost silent things, ask for >medium.
b >= a + margin and a >= medium and b <= high
then
log("new >= old + margin, old >= medium and new <= high.")
log("New source is significantly louder than old one.")
log("Transition: crossed, fade-out.")
add(fade.out(sa),sb)
elsif
# Opposite as the previous one.
a >= b + margin and b >= medium and a <= high
then
log("old >= new + margin, new >= medium and old <= high")
log("Old source is significantly louder than new one.")
log("Transition: crossed, fade-in.")
add(sa,fade.in(sb))
elsif
# Do not fade if it's already very low.
b >= a + margin and a <= medium and b <= high
then
log("new >= old + margin, old <= medium and new <= high.")
log("Do not fade if it's already very low.")
log("Transition: crossed, no fade.")
add(sa,sb)
# What to do with a loud end and a quiet beginning ?
# A good idea is to use a jingle to separate the two tracks,
# but that's another story.
else
# Otherwise, A and B are just too loud to overlap nicely,
# or the difference between them is too large and overlapping would
# completely mask one of them.
log("No transition: using default.")
default(sa, sb)
end
end
smart_cross(width=width, duration=start_next, conservative=conservative,
transition,s)
end
# Custom playlist source written using the script language.
# Will read directory or playlist, play all files and stop.
# Returns a pair @(reload,source)@ where @reload@ is a function
# of type @(?uri:string)->unit@ used to reload the source and @source@
# is the actual source. The reload function can optionally be called
# with a new playlist URI. Otherwise, it reloads the previous URI.
# @category Source / Input
# @param ~id Force the value of the source ID.
# @param ~random Randomize playlist content
# @param ~on_done Function to execute when the playlist is finished
# @param uri Playlist URI
def playlist.reloadable(~id="",~random=false,~on_done={()},uri)
# A reference to the playlist
playlist = ref []
# A reference to the uri
playlist_uri = ref uri
# A reference to know if the source
# has been stopped
has_stopped = ref false
# The next function
def next () =
file =
if list.length(!playlist) > 0 then
ret = list.hd(!playlist)
playlist := list.tl(!playlist)
ret
else
# Playlist finished
if not !has_stopped then
on_done ()
end
has_stopped := true
""
end
request.create(file)
end
# Instanciate the source
source = request.dynamic(id=id,next)
# Get its id.
id = source.id(source)
# The load function
def load_playlist () =
files =
if test_process("test -d #{quote(!playlist_uri)}") then
log(label=id,"playlist is a directory.")
get_process_lines("find #{quote(!playlist_uri)} -type f | sort")
else
playlist = request.create.raw(!playlist_uri)
result =
if request.resolve(playlist) then
playlist = request.filename(playlist)
files = playlist.parse(playlist)
def file_request(el) =
meta = fst(el)
file = snd(el)
s = list.fold(fun (cur, el) ->
"#{cur},#{fst(el)}=#{string.escape(snd(el))}", "", meta)
if s == "" then
file
else
"annotate:#{s}:#{file}"
end
end
list.map(file_request,files)
else
log(label=id,"Couldn't read playlist: request resolution failed.")
[]
end
request.destroy(playlist)
result
end
if random then
playlist := list.sort(fun (x,y) -> int_of_float(random.float()), files)
else
playlist := files
end
end
# The reload function
def reload(~uri="") =
if uri != "" then
playlist_uri := uri
end
log(label=id,"Reloading playlist with URI #{!playlist_uri}")
has_stopped := false
load_playlist()
end
# Load the playlist
load_playlist()
# Return
(reload,source)
end
# Custom playlist source written using the script language.
# Will read directory or playlist, play all files and stop
# @category Source / Input
# @param ~id Force the value of the source ID.
# @param ~random Randomize playlist content
# @param ~on_done Function to execute when the playlist is finished
# @param uri Playlist URI
def playlist.once(~id="",~random=false,~on_done={()},uri)
snd(playlist.reloadable(id=id,random=random,on_done=on_done,uri))
end
# Mixes two streams, with faded transitions between the state when only the
# normal stream is available and when the special stream gets added on top of
# it.
# @category Source / Track Processing
# @param ~delay Delay before starting the special source.
# @param ~p Portion of amplitude of the normal source in the mix.
# @param ~normal The normal source, which could be called the carrier too.
# @param ~special The special source.
def smooth_add(~delay=0.5,~p=0.2,~normal,~special)
d = delay
fade.final = fade.final(duration=d*2.)
fade.initial = fade.initial(duration=d*2.)
q = 1. - p
c = amplify
fallback(track_sensitive=false,
[special,normal],
transitions=[
fun(normal,special)->
add(normalize=false,
[c(p,normal),
c(q,fade.final(type="sin",normal)),
sequence([blank(duration=d),c(q,special)])]),
fun(special,normal)->
add(normalize=false,
[c(p,normal),
c(q,fade.initial(type="sin",normal))])
])
end
# Restrict a source to play only when a predicate is true.
# @category Source / Track Processing
# @param pred The predicate, typically a time interval such as \
# <code>{10h-10h30}</code>.
def at(pred,s)
switch([(pred,s)])
end
# Execute a given action when a predicate is true.
# This will be run in background.
# @category System
# @param ~freq Frequency for checking the predicate, in seconds.
# @param ~pred Predicate indicating when to execute the function, \
# typically a time interval such as <code>{10h-10h30}</code>.
# @param f Function to execute when the predicate is true.
def exec_at(~freq=1.,~pred,f)
def check()
if pred() then
f()
end
freq
end
add_timeout(freq,check)
end
# Register the replaygain protocol.
# @category Liquidsoap
def replaygain_protocol(arg,delay)
# The extraction program
extract_replaygain = "#{configure.libdir}/extract-replaygain"
x = get_process_lines("#{extract_replaygain} #{quote(arg)}")
if list.hd(x) != "" then
["annotate:replay_gain=\"#{list.hd(x)}\":#{arg}"]
else
[arg]
end
end
add_protocol("replay_gain", replaygain_protocol)
# Enable replay gain metadata resolver. This resolver will
# process any file decoded by liquidsoap and add a replay_gain
# metadata when this value could be computed. For a finer-grained
# replay gain processing, use the replay_gain protocol.
# @category Liquidsoap
# @param ~extract_replaygain The extraction program
def enable_replaygain_metadata(
~extract_replaygain="#{configure.libdir}/extract-replaygain")
def replaygain_metadata(file)
x = get_process_lines("#{extract_replaygain} \
#{quote(file)}")
if list.hd(x) != "" then
[("replay_gain",list.hd(x))]
else
[]
end
end
add_metadata_resolver("replay_gain", replaygain_metadata)
end
# Assign a new clock to the given source (and to other time-dependent
# sources) and return the source. It is a conveniency wrapper around
# clock.assign_new(), allowing more concise scripts in some cases.
# @category Liquidsoap
# @param ~sync Do not synchronize the clock on regular wallclock time, \
# but try to run as fast as possible (CPU burning mode).
def clock(~sync=true,~id="",s)
clock.assign_new(sync=sync,id=id,[s])
s
end
# Create a log of clock times for all the clocks initially present.
# The log is in a simple format which you can directly use with gnuplot.
# @category Liquidsoap
# @param ~interval Polling interval.
# @param ~delay Delay before setting up the clock logger. This should \
# be used to ensure that the logger starts only after \
# the clocks are created.
# @param unlabeled Path of the log file.
def log_clocks(~delay=0.,~interval=1.,logfile)
# Get the current clocks
clocks = list.map(fst,get_clock_status())
# Column headers
system("echo \# #{string.concat(separator=' ',clocks)} > #{(logfile:string)}")
def report()
status = get_clock_status()
status = list.map(fun (x) -> (fst(x),string_of(snd(x))), status)
status = list.map(fun (c) -> status[c], clocks)
system("echo #{string.concat(separator=' ',status)} >> #{logfile}")
interval
end
if delay<=0. then
add_timeout(interval,report)
else
add_timeout(delay,{add_timeout(interval,report) (-1.)})
end
end