input.pulseaudio usage in Linux with auto_null.monitor -> icecast stream.

[Oliver-Mardle]

How do I use the input.pulseaudio feature?

I keep getting either Error 2 or Error 5 and a large printout stating "this value has no method pulseaudio".
I'm trying to use the dummy output auto_null.monitor - I can record from this in FFMPEG okay.

Below is my test file:

pulseDevice = "auto_null.monitor"
radio = input.pulseaudio(id="Tunnel", device=pulseDevice, clock_safe=false)

output.icecast(%ffmpeg(format="mp3", %audio(codec="libmp3lame", b="320k")),
  host = "localhost", port = 8000,
  password = "example", mount = "test",
  radio, fallible = true)

[vitoyucepi]

Hi @Oliver-Mardle,

To properly identify the root cause of the problem, I need to ask you a couple of questions:

1. What operating system and version are you using?
2. What version of liquidsoap are you using?
3. How did you install liquidsoap?
4. Can you upload the result of the liquidsoap --build-config command?

[Oliver-Mardle]

Hi @vitoyucepi

The OS is Ubuntu.
Liquidsoap version is 2.2.4-1.
I believe it was installed using apt install.
Here's the build config - it looks as if pulseaudio is saying no... which is odd, as its definitely installed:

liquidsoap --build-config

 * Liquidsoap version  : 2.2.4-1

 * Compilation options
   - Release build       : true
   - Git SHA             : (none)
   - OCaml version       : 4.14.1
   - OS type             : Unix
   - Libs versions       : angstrom=0.15.0 asetmap=0.8.1 astring=0.8.5 base64=3.5.1 bigarray=[distributed with Ocaml] bigarray-compat=1.1.0 bigstringaf=0.9.1 bytes=[distributed with OCaml 4.02 or above] camlp-streams camomile.lib=2.0 cohttp=5.3.0 cohttp-lwt=5.3.0 cohttp-lwt-unix=5.3.0 conduit=6.2.0 conduit-lwt=6.2.0 conduit-lwt-unix=6.2.0 cry=1.0.3 ctypes=0.21.1 ctypes-foreign=0.21.1 ctypes.stubs=0.21.1 curl=0.9.2 domain-name=0.4.0 dtools=0.4.5 dune-build-info=3.11.1 dune-private-libs.dune-section=3.11.1 dune-site=3.11.1 dune-site.private=3.11.1 duppy=0.9.3 ffmpeg-av=1.1.10 ffmpeg-avcodec=1.1.10 ffmpeg-avdevice=1.1.10 ffmpeg-avfilter=1.1.10 ffmpeg-avutil=1.1.10 ffmpeg-swresample=1.1.10 ffmpeg-swscale=1.1.10 fileutils=0.6.4 fmt=0.9.0 gen=1.1 inotify=2.0-62-g5e58536 integers ipaddr=5.5.0 ipaddr-sexp=5.5.0 ipaddr.unix=5.5.0 jemalloc liquidsoap-lang=2.2.4-1 liquidsoap-lang.console=2.2.4-1 liquidsoap_builtins=f0fdb0e-dirty liquidsoap_core=f0fdb0e-dirty liquidsoap_ffmpeg=f0fdb0e-dirty liquidsoap_jemalloc=f0fdb0e-dirty liquidsoap_mem_usage=f0fdb0e-dirty liquidsoap_memtrace=f0fdb0e-dirty liquidsoap_optionals=f0fdb0e-dirty liquidsoap_oss=f0fdb0e-dirty liquidsoap_posix_time=f0fdb0e-dirty liquidsoap_prometheus=f0fdb0e-dirty liquidsoap_runtime=f0fdb0e-dirty liquidsoap_srt=f0fdb0e-dirty liquidsoap_ssl=f0fdb0e-dirty liquidsoap_stereotool=f0fdb0e-dirty liquidsoap_xmlplaylist=f0fdb0e-dirty liquidsoap_yaml=f0fdb0e-dirty logs=0.7.0 logs.fmt=0.7.0 logs.lwt=0.7.0 lwt=5.7.0 lwt.unix=5.7.0 macaddr=5.5.0 magic-mime=1.3.1 mem_usage=0.1.0 memtrace=0.2.3 menhirLib=20230608 metadata=0.3.0 mm=0.8.5 mm.audio=0.8.5 mm.base=0.8.5 mm.image=0.8.5 mm.midi=0.8.5 mm.video=0.8.5 ocplib-endian ocplib-endian.bigstring parsexp=v0.16.0 pcre=7.5.0 posix-base=5a7f328 posix-socket=5a7f328 posix-socket.constants=5a7f328 posix-socket.stubs=5a7f328 posix-socket.types=5a7f328 posix-time2=5a7f328 posix-time2.constants=5a7f328 posix-time2.stubs=5a7f328 posix-time2.types=5a7f328 posix-types=5a7f328 posix-types.constants=5a7f328 ppx_sexp_conv.runtime-lib=v0.16.0 prometheus=1.2 prometheus-app=1.2 re=1.11.0 sedlex=3.2 seq=[distributed with OCaml 4.07 or above] sexplib=v0.16.0 sexplib0=v0.16.0 srt=0.3.0 srt.constants=0.3.0 srt.stubs=0.3.0 srt.stubs.locked=0.3.0 srt.types=0.3.0 ssl=0.7.0 stdlib-shims=0.3.0 stereotool=f0fdb0e-dirty str=[distributed with Ocaml] stringext=1.6.0 threads=[distributed with Ocaml] threads.posix=[internal] unix=[distributed with Ocaml] unix-errno=52c6ecb unix-errno.errno_bindings=52c6ecb unix-errno.errno_types=52c6ecb unix-errno.errno_types_detected=52c6ecb unix-errno.unix=52c6ecb uri=4.4.0 uri-sexp=4.4.0 uri.services=4.4.0 xmlm=1.4.0 xmlplaylist=0.1.5 yaml=3.2.0 yaml.bindings=3.2.0 yaml.bindings.types=3.2.0 yaml.c=3.2.0 yaml.ffi=3.2.0 yaml.types=3.2.0
   - architecture        : arm64
   - host                : aarch64-unknown-linux-gnu
   - target              : aarch64-unknown-linux-gnu
   - system              : linux
   - ocamlopt_cflags     : -O2 -fno-strict-aliasing -fwrapv -pthread -fPIC
   - native_c_compiler   : gcc -O2 -fno-strict-aliasing -fwrapv -pthread -fPIC -D_FILE_OFFSET_BITS=64
   - native_c_libraries  : -lm

 * Configured paths
   - mode              : posix
   - standard library  : /usr/share/liquidsoap/libs
   - scripted binaries : /usr/share/liquidsoap/bin
   - rundir            : /var/run/liquidsoap
   - logdir            : /var/log/liquidsoap
   - camomile files    : /usr/share/liquidsoap/camomile

 * Supported input formats
   - MP3               : no (requires mad)
   - AAC               : no (requires faad)
   - Ffmpeg            : yes
   - Flac (native)     : no (requires flac)
   - Flac (ogg)        : no (requires ogg)
   - Opus              : no (requires opus)
   - Speex             : no (requires speex)
   - Theora            : no (requires theora)
   - Vorbis            : no (requires vorbis)

 * Supported output formats
   - FDK-AAC           : no (requires fdkaac)
   - Ffmpeg            : yes
   - MP3               : no (requires lame)
   - MP3 (fixed-point) : no (requires shine)
   - Flac (native)     : no (requires flac)
   - Flac (ogg)        : no (requires ogg)
   - Opus              : no (requires opus)
   - Speex             : no (requires speex)
   - Theora            : no (requires theora)
   - Vorbis            : no (requires vorbis)

 * Tags
   - Taglib (ID3 tags) : no (requires taglib)
   - Vorbis            : no (requires vorbis)

 * Input / output
   - ALSA              : no (requires alsa)
   - AO                : no (requires ao)
   - FFmpeg            : yes
   - GStreamer         : no (requires gstreamer)
   - JACK              : no (requires bjack)
   - OSS               : yes
   - Portaudio         : no (requires portaudio)
   - Pulseaudio        : no (requires pulseaudio)
   - SRT               : yes

 * Audio manipulation
   - FFmpeg            : yes
   - LADSPA            : no (requires ladspa)
   - Lilv              : no (requires lilv)
   - Samplerate        : no (requires samplerate)
   - SoundTouch        : no (requires soundtouch)
   - StereoTool        : yes

 * Video manipulation
   - camlimages        : no (requires camlimages)
   - FFmpeg            : yes
   - frei0r            : no (requires frei0r)
   - ImageLib          : no (requires imagelib)
   - SDL               : no (requires tsdl-image & tsdl-ttf)

 * MIDI manipulation
   - DSSI              : no (requires dssi)

 * Visualization
   - GD                : no (requires gd)
   - Graphics          : no (requires graphics)
   - SDL               : no (requires tsdl-image & tsdl-ttf)

 * Additional libraries
   - FFmpeg filters    : yes
   - FFmpeg devices    : yes
   - inotify           : yes
   - irc               : no (requires irc-client-unix)
   - jemalloc          : yes
   - lastfm            : no (requires lastfm)
   - lo                : no (requires lo)
   - memtrace          : yes
   - mem_usage         : yes
   - osc               : no (requires osc-unix)
   - ssl               : yes
   - tls               : no (requires tls-liquidsoap)
   - posix-time2       : yes
   - windows service   : no (requires winsvc)
   - YAML support      : yes
   - XML playlists     : yes

 * Monitoring
   - Prometheus        : yes

[vitoyucepi]

Looks like it was built from opam. It doesn't resemble any of the common builds for ubuntu.
I need some more info.

1. To get the OS release, run cat /etc/lsb-release.
2. To check if it was installed by apt run apt-cache policy liquidsoap.

[Oliver-Mardle]

Thanks @vitoyucepi

DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=22.04
DISTRIB_CODENAME=jammy
DISTRIB_DESCRIPTION="Ubuntu 22.04.4 LTS"

apt-cache policy liquidsoap
liquidsoap:
  Installed: (none)
  Candidate: 2.0.2-1build2
  Version table:
     2.0.2-1build2 500
        500 http://eu-west-1.ec2.ports.ubuntu.com/ubuntu-ports jammy/universe arm64 Packages
        100 /var/lib/dpkg/status

[vitoyucepi]

Well, I've turned this issue into an installation discussion, so I can explain to you how to install and configure liquidsoap from opam.

If you haven't done this yourself, it's probably best to ask the person who did it for you. I can walk you through it, but it may take a while.

1. I need to check the opam state.
   Run opam switch list to see the opam virtual environments.
   Run opam list to see the opam package list.
2. You are running on a remote server, aren't you? How do you plan to use pulseaudio? It's mainly used as a local sound server and not widely used to transfer sound from one computer to another.

[Oliver-Mardle]

I got it reinstalled in the end...! But now were facing another issue. running that same script, liquidsoap now loads for a short while, prints out "Killed" then closes.

Pulseaudio is streaming via a tunnel to the EC2 instance - that bit is all working, so its presenting a remote sound card as a source in the EC2 - that will then be pushed into a local Icecast server using Liquid soap - if all goes to plan.

[vitoyucepi]

prints out "Killed" then closes.

Looks like the work of an out-of-memory killer, I have no other reasonable explanation.

1. What are the hardware specifications of your EC2 instance?
2. Could you check the logs?
   I'm pretty sure that journalctl -r will show something valuable.
3. Memory usage can also depend on the OCaml version. 5.x.x can use up to three times more memory than 4.x.x. If you haven't changed anything since the last liquidsoap --build-config you should be fine.

[Oliver-Mardle]

Great - thank you very much!

Yup, As soon as I ran the script, memory usage shot up and the program crashed. Changed a few versions around and its all resolved now.

Many thanks again!