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Linux Sound Pipewire

Introduction to Pipewire

OBS Integration (Pipewire Plugin)

OBS Pipewire Plugin

Pipewire Download and Documents

Pipewire

PipeWire

• Capture and playback of audio and video with minimal latency.
• Real-time multimedia processing on audio and video.
• Multiprocess architecture to let applications share multimedia content.
• Seamless support for PulseAudio, JACK, ALSA, and GStreamer applications.
• Sandboxed applications support. See Flatpak for more info.

PipeWire is used by bitwik-studio

Getting Pipewire

git clone https://gitlab.freedesktop.org/pipewire/pipewire.git

Pipewire Documents

More Pipewire Help

Using tools pw-cat can be used to play and record audio and midi. Use pw-cat -h to get some more help. There are some aliases like pw-play and pw-record to make things easier:

$ pw-play /home/wim/data/01.\ Firepower.wav

Running JACK applications Depending on how the system was configured, you can either run PipeWire and JACK side-by-side or have PipeWire take over the functionality of JACK completely. In dual mode, JACK apps will by default use the JACK server. To direct a JACK app to PipeWire, you can use the pw-jack script like this:

$ pw-jack <appname>

If you replaced JACK with PipeWire completely, pw-jack does not have any effect and can be omitted. JACK applications will automatically use the buffer-size chosen by the server. You can force a maximum buffer size (latency) by setting the PIPEWIRE_LATENCY environment variable like so:

PIPEWIRE_LATENCY=128/48000 jack_simple_client

Requests the jack_simple_client to run with a buffer of 128 or less samples.

Pipewire and Pulse Audio

Running PulseAudio applications PipeWire can run a PulseAudio compatible replacement server. You can’t use both servers at the same time. Usually your package manager will make the server conflict so that you can only install one or the other. PulseAudio applications still use the regular PulseAudio client libraries and you don’t need to do anything else than change the server implementation. A successful swap of the server can be verified by checking the output of

pactl info

It should include the string:

Server Name: PulseAudio (on PipeWire 0.3.x)

You can use pavucontrol to change profiles and ports, change volumes or redirect streams, just like with PulseAudio.

Inspecting the PipeWire state

To inspect and manipulate the PipeWire graph via GUI, you can use Helvum. Alternatively, you can use use one of the excellent JACK tools, such as Carla, catia, qjackctl, …

However, you will not be able to see all features like the video ports.

pw-mon
pw-dot
pw-top
pw-dump
pw-cli

pw-mon dumps and monitors the state of the PipeWire daemon. pw-dot can dump a graph of the pipeline, check out the help for how to do this. pw-top monitors the real-time status of the graph. This is handy to find out what clients are running and how much DSP resources they use. pw-dump dumps the state of the PipeWire daemon in JSON format. This can be used to find out the properties and parameters of the objects in the PipeWire daemon. There is a more complicated tool to inspect the state of the server with pw-cli. This tool can be used interactively or it can execute single commands like this to get the server information:

$ pw-cli info 0