I have configured OBS in my Linux Mint and I am able to stream from my computer to Facebook Live, choosing different sources (a video, any of my monitors, any image file..). However, what I want to stream from is a remote mobile device, which should just send a video from its cam which I would like to process in OBS to set some watermarks and so on and emit from OBS to Facebook Live.
I have tried Zoom for the remote device to send the video, but it's more designed for a meeting, so it adds both remote and host captures in my video. What I would like to have is a raw streaming from remote in full screen in live. Just to make it clear, the person who uses the mobile device hasn't got any knowledge about video streaming - processing.
Note: by "video stream" I mean literally streaming a video, not just simply "screen sharing". So the software must be capable of that (e.g. Screen Stream does not suffice).