• v4l2loopback works in ubuntu 20.04 but the binary needs to be compiled:
  • get the headers for the kernel version you are using
  • from the package manager install v4l2loopback-source
  • cd /usr/src/v4l2loopback-0.12.3/
  • sudo make
• sudo modprobe v4l2loopback
• to create 2 devices modprobe v4l2loopback devices=2 (untested but in the docs)

• import v4l2
  • fix bug
• the magic sauce is virtualvideo. Trying to convert/write raw video seemed like a dead end:
  • import virtualvideo
  • in the example code: fvd.init_output(2, 1280, 720, fps=30) the first parameter (2) is the video #

• |pix_record| is the magic sauce. Send it codec 33 and open file /dev/video[NUMBER]
  • example

For code completion to work you need to downgrade openCV :(

• from the terminal inside Pycharm: pip install --force-reinstall --no-cache -U opencv-python==4.5.5.62