+++ /dev/null
----
-title: PipeWire / WirePlumber
----
-
-# PipeWire / WirePlumber
-
-## Overview
-
-AGL uses the PipeWire daemon service to provide audio playback and capture capabilities.
-PipeWire is accompanied by a secondary service, WirePlumber (also referred to as the
-*session manager*), which provides policy management, device discovery, configuration and more.
-
-Applications can connect to the PipeWire service through its UNIX socket, by using either the
-*libpipewire* or *libwireplumber* libraries as a front-end to that socket.
-
-Upstream documentation for these components can be found at the links below:
-
-- [PipeWire documentation](https://docs.pipewire.org/)
-
-- [WirePlumber documentation](https://pipewire.pages.freedesktop.org/wireplumber/)
-
-- [PipeWire Wiki](https://gitlab.freedesktop.org/pipewire/pipewire/-/wikis/home)
-
-## APIs
-
-### libpipewire
-
-The main entry point for applications to access the audio system is the API offered by
-*libpipewire*. The functionality offered by *libpipewire* is vast and it is beyond the
-scope of this document to describe it all.
-
-For playback and capture, applications should use *struct pw_stream* and its associated methods.
-See [PipeWire: Tutorial - Part 4: Playing a tone](https://docs.pipewire.org/page_tutorial4.html)
-for a starting point.
-
-### GStreamer (Recommended)
-
-For convenience, applications that use GStreamer can use the PipeWire GStreamer elements to
-plug the functionality offered by *struct pw_stream* directly in the GStreamer pipeline. These
-elements are called *pipewiresrc* and *pipewiresink*
-
-Example:
-
-```shell
-> gst-launch-1.0 audiotestsrc ! pipewiresink
-```
-
-Through these elements, it is possible to specify the application role by setting it in the
-*stream-properties* property of the element, as shown below:
-
-```shell
-> gst-launch-1.0 audiotestsrc ! pipewiresink stream-properties="p,media.role=Multimedia""
-```
-
-or, in the C API:
-
-```c
-gst_util_set_object_arg (sink, "stream-properties", "p,media.role=Multimedia");
-```
-
-Of course, it is also possible to use *alsasink* and *alsasrc* and route audio through the
-virtual ALSA device that is mentioned below. This is also the default behavior of *playbin*
-and similar auto-plugging elements, because the PipeWire GStreamer elements are not autoplugged
-(this may change in a future version).
-
-### ALSA
-
-PipeWire offers a virtual ALSA device (called *pipewire*) that redirects audio to PipeWire
-through an ALSA PCM plugin. This device is the default one, so unless you explicitly specify
-a device in your ALSA client application, audio will go through PipeWire instead.
-
-Example:
-
-```shell
-> aplay sound.wav # the default device is 'pipewire'
-> aplay -D pipewire sound.wav
-```
-
-In order to specify the application role while using the ALSA compatibility device, pass the role
-as a device parameter like this:
-
-```shell
-> aplay -D pipewire:ROLE=Navigation turnleft.wav
-```
-
-### Audiomixer service
-
-See the separate [agl-service-audiomixer](https://git.automotivelinux.org/apps/agl-service-audiomixer/about/) documentation.
-
-### libwireplumber
-
-The WirePlumber library provides API that wraps libpipewire and makes it easier to work with
-when you are writing control applications, such as a volume mixer. The audiomixer service is in
-fact implemented using *libwireplumber*.
-
-WirePlumber also provides support for lua-based scripting. Standalone scripts, executed with the
-*wpexec* tool, may be used as a means to rapidly make use of the API provided by *libwireplumber*
-
-## Tools
-
-* **wpctl**: allows inspecting the devices, choosing which source & sink are the default ones
- and allows volume/mute adjustments to be made on the command line. Try `wpctl status` and
- `wpctl help` to get started with it
-
-* **wpexec**: allows running wireplumber lua scripts standalone, which is useful to implement
- custom scripts to interact with PipeWire
-
-* **pw-cli**: this is the main tool for interacting with pipewire directly
-
-* **pw-dump**: dumps all the objects in the pipewire graph to a big JSON. The output of this
- tool is very useful to include in bug reports. It is also suitable for implementing scripts
- that parse information with jq
-
-* **pw-dot** is a useful debug tool that dumps the objects in a dot graph for easy visualization
-
-* **pw-cat / pw-play / pw-record**: This is a set of tools similar to aplay/arecord, for simple
- audio operations
-
-* **pw-top**: This is a performance measurement tool that shows realtime timing information
- about the audio pipeline. Before running this tool, you will need to uncomment the loading
- of "libpipewire-module-profiler" in /etc/pipewire/pipewire.conf and restart pipewire
-
-## Systemd Integration
-
-The PipeWire service, `pipewire.service`, is activated on demand, via systemd socket activation,
-by `pipewire.socket`. The WirePlumber service, `wireplumber.service`, is bound to the pipewire
-service and therefore started and stopped together with the PipeWire service.
-
-If you wish to manually stop or restart both services, you can do so by using *systemctl*,
-operating on the *.socket* unit:
-
-```shell
-> systemctl restart pipewire.socket
-> systemctl stop pipewire.socket
-```
-
-## Debugging
-
-The PipeWire daemon can be configured to be more verbose by editing
-**/etc/pipewire/pipewire.conf** and setting `log.level=n` (n=0-5) in section
-`context.properties`.
-
-Similarly, the WirePlumber daemon can be configured to be more verbose by editing
-**/etc/wireplumber/wireplumber.conf** and setting `log.level=n` (n=0-5) in section
-`context.properties`.
-
-All messages will be available in the systemd journal, inspectable with journalctl.
-
-For applications, at runtime, `PIPEWIRE_DEBUG` can be set to a value between 0 and 5,
-with 5 being the most verbose and 0 the least verbose.
-
-For applications that use *libwireplumber* the equivalent environment variable is
-`WIREPLUMBER_DEBUG`, which also takes values between 0 and 5.
-
-The default debug level for the daemons is 2, while for applications it's 0
-(with few exceptions).
-
-More information is also available on
-[WirePlumber's documentation on debug logging](https://pipewire.pages.freedesktop.org/wireplumber/daemon-logging.html)
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