ea28343166
Avoid doing conversions in the nodes between Midi formats, just assume the imput is what we expect and output what we naturally produce. For ALSA this means we produce and consume Midi1 or Midi2 depending on the configurtation. All of the other modules (ffado, RTP, netjack and VBAN) really only produce and consume MIDI1. Set the default MIDI format to MIDI1 in ALSA. Whith this change, almost everything now produces and consumes MIDI1 again (previously the buffer format was forced to MIDI2). The problem is that MIDI2 to and from MIDI1 conversion has problems in some cases in PipeWire and ALSA and breaks compatibility with some hardware. The idea is to let elements produce their prefered format and that the control mixer also negotiates and converts to the node prefered format. There is then a mix of MIDI2 and MIDI1 on ports but with the control port adapting, this should not be a problem. There is one remaining problem to make this work, the port format is taken from the node port and not the mixer port, which would then expose the prefered format on the port and force negotiation to it with the peer instead of in the mixer. See #5183 |
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| .gitlab | ||
| doc | ||
| include/valgrind | ||
| pipewire-alsa | ||
| pipewire-jack | ||
| pipewire-v4l2 | ||
| po | ||
| spa | ||
| src | ||
| subprojects | ||
| test | ||
| .codespell-ignore | ||
| .editorconfig | ||
| .gitattributes | ||
| .gitignore | ||
| .gitlab-ci.yml | ||
| autogen.sh | ||
| CODE_OF_CONDUCT.md | ||
| COPYING | ||
| INSTALL.md | ||
| LICENSE | ||
| Makefile.in | ||
| meson.build | ||
| meson_options.txt | ||
| NEWS | ||
| pw-uninstalled.sh | ||
| README.md | ||
| template.test.in | ||
PipeWire
PipeWire is a server and user space API to deal with multimedia pipelines. This includes:
- Making available sources of video (such as from a capture devices or application provided streams) and multiplexing this with clients.
- Accessing sources of video for consumption.
- Generating graphs for audio and video processing.
Nodes in the graph can be implemented as separate processes, communicating with sockets and exchanging multimedia content using fd passing.
Building and installation
The preferred way to install PipeWire is to install it with your distribution package system. This ensures PipeWire is integrated into the rest of your system for the best experience.
If you want to build and install PipeWire yourself, refer to install for instructions.
Usage
The most important purpose of PipeWire is to run your favorite apps.
Some applications use the native PipeWire API, such as most compositors (gnome-shell, wayland, ...) to implement screen sharing. These apps will just work automatically.
Most audio applications can use either ALSA, JACK or PulseAudio as a backend. PipeWire provides support for all 3 backends. Depending on how your distribution has configured things this should just work automatically or with the provided scripts shown below.
PipeWire can use environment variables to control the behaviour of applications:
PIPEWIRE_DEBUG=<level>to increase the debug level (or use one ofXEWIDTfor none, error, warnings, info, debug, or trace, respectively).PIPEWIRE_LOG=<filename>to redirect log to filenamePIPEWIRE_LOG_SYSTEMD=falseto disable logging to systemd journalPIPEWIRE_LATENCY=<num/denom>to configure latency as a fraction. 10/1000 configures a 10ms latency. Usually this is expressed as a fraction of the samplerate, like 256/48000, which uses 256 samples at a samplerate of 48KHz for a latency of 5.33ms. This function does not attempt to configure the samplerate.PIPEWIRE_RATE=<num/denom>to configure a rate for the graph.PIPEWIRE_QUANTUM=<num/denom>to configure latency as a fraction and a samplerate. This function will force the graph samplerate todenomand force the specifiednumas the buffer size.PIPEWIRE_NODE=<id>to request a link to the specified node. The id can be a node.name or object.serial of the target node.
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.
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.
Running ALSA applications
If the PipeWire alsa module is installed, it can be seen with
$ aplay -L
ALSA applications can then use the pipewire: device to use PipeWire
as the audio system.
Running GStreamer applications
PipeWire includes 2 GStreamer elements called pipewiresrc and
pipewiresink. They can be used in pipelines such as this:
$ gst-launch-1.0 pipewiresrc ! videoconvert ! autovideosink
Or to play a beeping sound:
$ gst-launch-1.0 audiotestsrc ! pipewiresink
PipeWire provides a device monitor as well so that
$ gst-device-monitor-1.0
shows the PipeWire devices and applications like cheese will automatically use the PipeWire video source when possible.
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 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
Documentation
Find tutorials and design documentation here.
The (incomplete) autogenerated API docs are here.
The Wiki can be found here
Contributing
PipeWire is Free Software and is developed in the open. It is mostly licensed under the MIT license. Check LICENSE for more details about the exceptions.
Contributors are encouraged to submit merge requests or file bugs on gitlab.
Join us on IRC at #pipewire on OFTC.
We adhere to the Contributor Covenant for our code of conduct.
Getting help
You can ask for help on the IRC channel (see above). You can also ask questions by raising a gitlab issue.