https://github.com/hzeller/rpi-rgb-led-matrix/tree/master/utils#video-viewer
yt-dlp "https://www.youtube.com/watch?v=s9X0_Vb-4zc" -f 'bestvideo[height<=360]' --external-dow
nloader ffmpeg --external-downloader-args "-ss 00:00:00 -to 00:01:00" -o "%(title)s_method2.%(ext)s"
sudo ./video-viewer --led-gpio-mapping=adafruit-hat --led-rows=64 --led-cols=64 --led-chain=4 --led-slowdown-gpio=2 ~/Downloads/bright-abstract-animation-360p.webm -F -f
-f
loop forever-F
fullscreen-V<n>
slows down video to n led cycles per frame