https://twitter.com/Benjojo12/status/1380527716894711813

combine.sh

# Glues 4 files into one

ffmpeg -i 1xtra.wav.mp4 -i radio1.wav.mp4 -i radio2.wav.mp4 -i radio4.wav.mp4 -filter_complex "
		nullsrc=size=640x480 [base];
		[0:v] setpts=PTS-STARTPTS, scale=320x240 [upperleft];
		[1:v] setpts=PTS-STARTPTS, scale=320x240 [upperright];
		[2:v] setpts=PTS-STARTPTS, scale=320x240 [lowerleft];
		[3:v] setpts=PTS-STARTPTS, scale=320x240 [lowerright];
		[base][upperleft] overlay=shortest=1 [tmp1];
		[tmp1][upperright] overlay=shortest=1:x=320 [tmp2];
		[tmp2][lowerleft] overlay=shortest=1:y=240 [tmp3];
		[tmp3][lowerright] overlay=shortest=1:x=320:y=240;
		[0:a] amix=inputs=4:duration=first:dropout_transition=4
	" -c:v libx264 -pix_fmt yuv420p radio-opt-out.mp4

vis.sh

#! /bin/sh
#Makes single file vis


Title=$(echo $1 | awk -F '.' '{print $1}')

ffmpeg -y -i "$1" -filter_complex "
[0:a]showvolume,scale=852:-1,pad=852:480:(ow-iw)/2:(oh-ih)/2[v]" -map '[v]' -map '0:a' \
-pix_fmt yuv420p -f nut - | ffmpeg -f nut -i - -vf drawtext="fontfile=/path/to/font.ttf: \
text='$Title': fontcolor=white: fontsize=24: box=1: boxcolor=black@0.5: \
boxborderw=5: x=(w-text_w)/2: y=(h-text_h)/2" "$1.mp4"