Liquidsoap

From XPUB & Lens-Based wiki
Website http://liquidsoap.info/
License GPL
OS GNU/Linux, OS X, Windows
Media Streaming media
Format OGG, MP3
Interface Custom programming language
Wikipedia http://en.wikipedia.org/wiki/Draft:Liquidsoap
Thumbnail
Liquidsoap-logo.png


Sound processing

liquidsoap can be used to process / filter sound either in a streaming pipeline, or used "offline" to directly produce an audio output (file).

See https://www.liquidsoap.info/doc-1.4.2/reference.html#source-sound-processing


Links / Projects / Radio streams that use liquidsoap

  • Data Radio. Here a script created a day and night playlist, with a "fallback" to allow a live stream to interrupt.

playlist

playlist source

mode (of type string, which defaults to "randomize"): Play the files in the playlist either in the order (“normal” mode), or shuffle the playlist each time it is loaded, and play it in this order for a whole round (“randomize” mode), or pick a random file in the playlist each time (“random” mode).

say_metadata

say_metadata filter

outputs

Basic outputs of interest:

examples

liquidsoap 'out(noise())'
liquidsoap 'out(playlist("playlist.pls"))'
liquidsoap 'output.prefered(mksafe(playlist("playlist.pls")))'
liquidsoap 'output.file(%mp3,"output.mp3",mksafe(playlist("playlist.pls")))'

with playlist.pls:

brown.ogg

Observations:

  • WAV files don't seem to work, but ogg + mp3 seem OK! (or was this the stereo problem)
  • explicit output modules (like output.file) seem to require the use of mksafe (out doesn't need this).

Doesn't work with mono source material -- default seems to be stereo...

  [decoder:3] Unable to decode "./speech0001.mp3" as {audio=2;video=0;midi=0}!
  2020/05/11 17:42:04 [decoder.mad:3] File "./speech0003.mp3" has an incompatible number of channels.


How would you output a mono audio stream?