gistfile1.txt

#!/bin/bash
ffmpeg -hide_banner -y -nostdin -f decklink -list_devices 1 -i dummy 2>&1 | head -n -1 | tail -n +2 | cut -c 31- | cut -c -1 | while read device; do
	ffmpeg -hide_banner -y -nostdin -f decklink -list_formats 1 -i $device 2>&1 | head -n -1 | tail -n +4 | cut -c 2- | cut -f1 -d'	' | while read mode; do
		for plug in sdi hdmi; do

			desc="$device@$mode on $plug"
			echo "-> /tmp/$desc.png"
			ffmpeg -v warning -hide_banner -y -nostdin -f decklink -video_input $plug -format_code $mode\
				-i "$device" \
				-ss 1 -vframes 1 \
				"/tmp/$desc.png"

		done
	done
done