mirrors/pipewire
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/pipewire/pipewire.git synced 2025-12-14 08:56:37 -05:00
Code Issues Projects Releases Packages Wiki Activity Actions

doc: reword the Design page

Browse source
This commit is contained in:
Peter Hutterer 2021-07-29 14:43:40 +10:00
parent 6da0ee6cb5
commit c03fedbac2
1 changed files with 25 additions and 18 deletions
Download patch file Download diff file Expand all files Collapse all files

43
doc/pipewire-design.dox
View file

@ -1,35 +1,39 @@
/** \page page_design Design /** \page page_design Design
A short overview of PipeWire's design.
PipeWire is a media server that can run graphs of multimedia nodes. PipeWire is a media server that can run graphs of multimedia nodes.
Nodes can run inside the server or in separate processes. Nodes can run inside the server process or in separate processes,
communicating with the server.
Some of the requirements are: PipeWire was designed to
- must be efficient for raw video using fd passing and audio with - be efficient for raw video using fd passing and audio with
shared ringbuffers shared ringbuffers
- must be able to provide/consume/process media from any process - be able to provide/consume/process media from any process
- policy to restrict access to devices and streams - provide policy to restrict access to devices and streams
- extensible - be easily extensible
Although an initial goal, the design is not limited to raw video Although an initial goal, the design is not limited to raw video
only and should be able to handle compressed video and other only and should be able to handle compressed video and other
media as well. media as well.
PipeWire uses the SPA plugin API for the nodes in the graph. SPA is PipeWire uses the \ref page_spa "SPA plugin API" for the nodes in the graph.
a plugin API designed for low-latency and efficient processing of SPA is designed for low-latency and efficient processing of any multimedia
any multimedia format. format. SPA also provides a number of helper utilities that are not available
in the standard C library.
Some of the application we intend to build Some of the application we intend to build
- v4l2 device provider. Provide controlled access to v4l2 devices - v4l2 device provider: Provide controlled access to v4l2 devices
and share 1 device between multiple processes. and share one device between multiple processes.
- gnome-shell video provider. Gnome-shell provides a node that - gnome-shell video provider: GNOME Shell provides a node that
gives the contents of the frame buffer for screen sharing or gives the contents of the frame buffer for screen sharing or
screen recording. screen recording.
- audio server. Mix and playback multiple audio streams. The design - audio server: Mix and playback multiple audio streams. The design
is more like CRAS (Chromium audio server) than pulseaudio and with is more like CRAS (Chromium audio server) than PulseAudio and with
the added benefit that processing can be arranged in a graph. the added benefit that processing can be arranged in a graph.
- Pro audio graph processing like JACK. - Pro audio graph processing like JACK.
@ -40,9 +44,11 @@ Some of the application we intend to build
Protocol Protocol
-------- --------
The native protocol and object model is similar to wayland but with custom The native protocol and object model is similar to
[Wayland](https://wayland.freedesktop.org) but with custom
serialization/deserialization of messages. This is because the datastructures serialization/deserialization of messages. This is because the datastructures
in the messages are more complicated and not easily expressible in xml format. in the messages are more complicated and not easily expressible in XML.
See \ref page_module_protocol_native for details.
Extensibility Extensibility
@ -51,7 +57,8 @@ Extensibility
The functionality of the server is implemented and extended with modules and The functionality of the server is implemented and extended with modules and
extensions. Modules are server side bits of logic that hook into various extensions. Modules are server side bits of logic that hook into various
places to provide extra features. This mostly means controlling the processing places to provide extra features. This mostly means controlling the processing
graph in some way. graph in some way. See \ref page_pipewire_modules for a list of current
modules.
Extensions are the client side version of the modules. Most extensions provide Extensions are the client side version of the modules. Most extensions provide
both a client side and server side init function. New interfaces or new object both a client side and server side init function. New interfaces or new object
@ -65,7 +72,7 @@ Some of the extensions that can be written
- a module to check security of method calls - a module to check security of method calls
- a module to automatically create or link or relink nodes - a module to automatically create, link or relink nodes
- a module to suspend idle nodes - a module to suspend idle nodes