Table of Contents

Google's authenticator

Google Authenticator is based on and implements the Time-based One-Time Password (TOTP) algorithm specified in RFC 6238. 6-digit code.

read image from file

zbarimg -q Screenshot.png 
QR-Code:otpauth://totp/Google%3Auser%40example.com?secret=base32secret&issuer=Google

generate QR from command line

qrencode -t ANSI256UTF8 'otpauth://totp/Google%3Auser%40example.com?secret=base32secret&issuer=Google'