# sudo modprobe v4l2loopback video_nr=4,5 max_buffers=2 exclusive_caps=1,1
card_label="Webcam","VirtualCam
# gphoto2 --set-config /main/actions/autofocus=1
# gphoto2 --stdout --capture-movie | gst-launch-1.0 fdsrc ! decodebin3 name=dec ! queue ! videoconvert ! v4l2sink device=/dev/video4