Install the tools:
sudo apt install qrencode zbar-tools
Create the source:
nano text_for_QR_code.txt
MECARD:N:Dr AN Other;TEL:+441234123456;EMAIL:AN Other <ANOther@other.org>;NOTE:Director;ADR:123 Other Street, London, A1N 2OT, United Kingdom;URL:https://other.org;
Generate the corresponding QR codes:
qrencode -t PNG -r text_for_QR_code.txt -l H -o QR.png
convert QR_2023.png QR_2023.jpg
qrencode -t ASCII -r text_for_QR_code.txt -l H -o QR_2023.txt
cat QR_2023.txt | sed 's/#/█/g' > QR_2023_utf8.txt
Useful links:
Notes primarily to myself, but perhaps also useful for someone else…