There is a new API coming with Windows 11. Finally we will get well defined way to register virtual cameras (perhaps for applications built against Windows Media Foundation API, not DirectShow): MFCreateVirtualCamera.
Creates a virtual camera object which can be used by the caller to register, unregister, or remove the virtual camera from the system.
Frame server reference is a good sign and suggests that an application might be able to register its own implementation, then system wide service would act as a proxy and expose the implementation to video capture applciations built to work with cameras.
MFVirtualCameraType_SoftwareCameraSource “The virtual camera is a software camera source.”
There already is a sample on GitHub for this API: Windows-Camera/Samples/VirtualCamera at master ยท microsoft/Windows-Camera (github.com)
See also:
Some other interesting things are also coming, e.g. “virtual audio device that supports audio loopback based on a process ID instead of the device interface path of a physical audio device” (AUDIOCLIENT_ACTIVATION_TYPE_PROCESS_LOOPBACK and friends). We will be able to re-capture individual process audio, whcih is a cool new one, but keep patience: new stuff is scheduled for Windows 10 Build 20348.