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ffmpeg -f lavfi -i "mandelbrot" -filter_complex "noise=alls=60:allf=t+u" -codec:v rawvideo -pix_fmt rgb24 -f v4l2 /dev/video0
ffmpeg -f lavfi -i "mandelbrot" -filter_complex "noise=alls=60:allf=t+u" -codec:v rawvideo -pix_fmt rgb24 -f v4l2 /dev/video0
yes, you *can* just tell ffmpeg "give me an mandelbrot, forever"
yes, this command does work if you have v4l2loopback enabled on /dev/video0