#!/bin/bash
ffmpeg \
-f x11grab -framerate 30 -video_size 1920x1080 -i :0 `# this is screen` \
-f v4l2 -framerate 30 -video_size 640x480 -i /dev/video0 `# this is camera` \
-f alsa -i default `# this is audio` \
-filter_complex "[0][1]overlay=main_w-overlay_w-2:main_h-overlay_h-2[v]" -map [v] -map 2 `# this is for placing camera in bottom right corner. IDK how it works` \
video.mp4 # ouput file