PipeWire support for Qubes Video Companion’s receiver

[DemiMarie]

How to file a helpful issue

The problem you're addressing (if any)

Qubes Video Companion currently relies on an out of tree kernel module (v4l2loopback). Furthermore, users must manually attach a camera when needed, and hotplugging a camera often fails.

This is the cause of #9639.

The solution you'd like

Use PipeWire instead of v4l2loopback. The PipeWire module can make a qrexec call when image data is requested, thus prompting the user.

The value to a user, and who that user might be

All users who rely on qubes-video-companion will be automatically prompted to allow video recording when needed. No out of tree kernel module will be required, so in-VM kernels will work. Users will not run into bugs like #9639.

Completion criteria checklist

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