ffmpeg \
-f x11grab \
-y \
-framerate 20 \
-s "$(xdpyinfo | grep dimensions | awk '{ print $2 }' )" \
-i :0.0 \
-c:v libx264 \
-preset superfast \
-crf 21 \
"$(date +'%Y-%m-%d_%H-%M-%S').mp4"