IIRC, OBS makes it virtual webcam usable to other applications. I haven't gone through their sources though so I currently don't know how they do it.

I added the following two lines of code and it worked:

QHBoxLayout *camera_layout = new QHBoxLayout(this); mCamera = new QCamera(); mCameraViewfinder = new QCameraViewfinder(); camera_layout->addWidget(mCameraViewfinder); mCamera->setViewfinder(mCameraViewfinder); mCamera->start();

And it worked

You're welcome !

If you would like to use the latest version of gstreamer, you'll likely have to re-build the QtMultimedia backend.

Hi and welcome to devnet,

You should be able to achieve that by QCamera + QCameraViewFinder. QCameraViewFinder should show you the current content of the camera.