Beyond Linux® From Scratch (systemd edition) - Version 7.10

Chapter 44. Multimedia Libraries and Drivers

PulseAudio-9.0

Introduction to PulseAudio

PulseAudio is a sound system for POSIX OSes, meaning that it is a proxy for sound applications. It allows you to do advanced operations on your sound data as it passes between your application and your hardware. Things like transferring the audio to a different machine, changing the sample format or channel count and mixing several sounds into one are easily achieved using a sound server.

This package is known to build and work properly using an LFS-7.10 platform.

Package Information

PulseAudio Dependencies

Required

JSON-C-0.12.1 and libsndfile-1.0.27

Recommended

alsa-lib-1.1.2, D-Bus-1.10.10, GLib-2.48.2, libcap-2.25 with PAM, OpenSSL-1.0.2h, Speex-1.2rc2 and Xorg Libraries

Optional

Avahi-0.6.32, BlueZ-5.41 (runtime), Check-0.10.0, GConf-3.2.6, GTK+-3.20.9, libsamplerate-0.1.8, SBC-1.3 (Bluetooth support), Valgrind-3.11.0, FFTW, JACK, libasyncns, LIRC, ORC, TDB, WebRTC AudioProcessing and XEN

User Notes: http://wiki.linuxfromscratch.org/blfs/wiki/pulseaudio

Installation of PulseAudio

[Note]

Note

The build procedure emits a lot of invalid warnings. If desired, remove them with: 

sed -i "/seems to be moved/s/^/#/" build-aux/ltmain.sh

Install PulseAudio by running the following commands: 

./configure --prefix=/usr        \
            --sysconfdir=/etc    \
            --localstatedir=/var \
            --disable-bluez4     \
            --disable-rpath      &&
make

To test the results, issue: make check.

Now, as the root user: 

make install

While still as the root user, remove the D-Bus configuration file for the system wide daemon to avoid creating unnecessary system users and groups: 

rm /etc/dbus-1/system.d/pulseaudio-system.conf

Command Explanations

--disable-bluez4: This switch disables support for BlueZ version 4 in favour of BlueZ version 5 since the latter also installs compatibility library for the earlier version.

--disable-rpath: This switch prevents linker from adding a hardcoded runtime path to the installed programs and libraries.

Configuring PulseAudio

Config Files

There are system wide configuration files: /etc/pulse/daemon.conf, /etc/pulse/client.conf, /etc/pulse/default.pa, and user configuration files with the same names in ~/.config/pulse. User configuration files take precedence over system wide ones.

Configuration Information

The default configuration files allow setting up a working installation. However, a reference to Console-Kit needs to be removed if it is not installed. For example, issue the following command as the root user: 

sed -i '/load-module module-console-kit/s/^/#/' /etc/pulse/default.pa

You may also have to configure the audio system. You can start pulseaudio in command line mode using pulseaudio -C and then list various information and change settings. See man pulse-cli-syntax.

Contents

Installed Programs: esdcompat, pacat, pacmd, pactl, padsp, pamon (symlink to pacat), paplay (symlink to pacat), parec (symlink to pacat), parecord (symlink to pacat), pasuspender, pax11publish, pulseaudio, and start-pulseaudio-x11
Installed Libraries: libpulse-mainloop-glib.so, libpulse-simple.so and libpulse.so
Installed Directories: /etc/pulse, /usr/include/pulse, /usr/lib/cmake/PulseAudio, /usr/lib/{pulseaudio,pulse-9.0}, /usr/libexec/pulse, and /usr/share/pulseaudio

Short Descriptions

esdcompat

is the PulseAudio ESD wrapper script.

pacat

plays back or records raw or encoded audio streams on a PulseAudio sound server.

pacmd

is a tool used to reconfigure a PulseAudio sound server during runtime.

pactl

is used to control a running PulseAudio sound server.

padsp

is the PulseAudio OSS Wrapper.

pamon

is a symbolic link to pacat.

paplay

is used to play audio files on a PulseAudio sound server.

parec

is a symbolic link to pacat.

parecord

is a symbolic link to pacat.

pasuspender

is a tool that can be used to tell a local PulseAudio sound server to temporarily suspend access to the audio devices, to allow other applications to access them directly.

pax11publish

is the PulseAudio X11 Credential Utility.

pulseaudio

is a networked low-latency sound server for Linux.

start-pulseaudio-x11

starts PulseAudio and registers it to the X11 session manager.

Last updated on 2016-08-27 13:19:14 -0700