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PipeWire video devices

PipeWire Video Input and PipeWire Video Output connect textures to Linux PipeWire streams. They require a build with PipeWire video I/O enabled, a running PipeWire server and compatible producers or consumers. These are video devices, distinct from choosing PipeWire as score’s audio driver.

Receive video

Add PipeWire Video Input. PipeWire Node lists live sources; choose (default source) for automatic connection, a specific source, or (unconnected: link it yourself) for manual patching in a PipeWire routing tool.

Width, Height, Frame Rate and Pixel Format are negotiation preferences, not a demand that the producer change its stream. Any leaves the pixel-format choice open. The device advertises compatible alternatives and uses the format and dimensions actually agreed with the source. Selecting a live source can update the proposed settings from its advertised capabilities.

Assign the device to a texture inlet, then route the process’s texture output to a window or other destination. This does not request desktop-capture permission: for a Wayland screen picker, use Window Capture, described on the Camera device page.

Publish video

Add PipeWire Video Output, choose Width, Height, Rate and Pixel Format, then assign the device as the destination of a texture outlet. Target lists live consumers, automatic connection, and the unconnected option for manual linking. The PipeWire node field supplies the path/target information used by this device.

Output format choices are the renderable subset, not all formats accepted on input. The normal path renders a texture, reads it back and publishes shared-memory buffers. Higher precision choices require a compatible consumer; selecting a float format alone does not establish an HDR display chain.

DMA-BUF and fallback

Zero-copy DMA-BUF negotiates shared GPU buffers where possible:

  • On input, it is enabled by default and shared memory remains offered. The producer chooses a compatible transport. Turn it off to isolate modifier or GPU-import problems.
  • On output, it is optional. The current accelerated output is restricted to RGBA. Vulkan needs exportable DMA-BUF images and the relevant DRM-modifier/external-memory capabilities; OpenGL needs an EGL/GBM path. Other formats or unavailable export paths use CPU readback instead.
  • DMA-BUF depends on both ends, their GPUs and supported modifiers. It is not guaranteed for every Linux session, cross-GPU route or pixel format. The accelerated output can still perform a GPU copy; “zero-copy” here does not mean no GPU work.
  • If a negotiated DMA-BUF buffer cannot acquire a backing image, frames may be dropped with a diagnostic. Disable DMA-BUF and reconnect to use shared memory; not every late allocation failure can be repaired transparently.

The saved input path has the form pipewire://node-name?width=1280&height=720&fps=30&format=rgba; dmabuf=off disables GPU-buffer negotiation. Output paths use a node/target name with options such as ?format=rgba&dmabuf=on. Prefer the dialog controls rather than constructing paths manually.

See GStreamer for pipelines and audio/video together, Window for display output, and Video formats and color for precision and color considerations.