An Approach for Securing QR code using Cryptography and Visual Cryptography

Quick Response code (QR code) is a 2-D matrix barcode which stores data in four different encoding modes (numeric, alphanumeric, kanji, binary). They are widely used nowadays and can be seen almost everywhere whether it is on cosmetics products, general stores, billboards and so on. It has become an important part of day to day activities. As an information sharing medium, it has become so user friendly and mobile-friendly that with just one scan through smart phones you get the information stored in it. The main intent of this work is to secure QR code from unauthorized access by allowing only those who have authorization to access it by using cryptography (by encrypting and decrypting the QR code using a key value). And further security was enhanced by applying ‘k’ out of ‘n’ visual cryptography scheme on the QR code. It creates ‘n’ no. of share of the QR code out of which ‘k’ no. of shares is required to restore it. This work will briefly explain how cryptography and visual cryptography were used to secure the QR code. The experimental results showed that there was no data loss during this process. Also, if at the time of decryption wrong key is entered then the QR code will not be generated. And also it is required to input minimum k number of generated shares of the QR code for the successful retrieval of QR code. Quality of the reconstructed QR code was also measured using PSNR and SSIM which showed that reconstructed QR code was of good quality as well as original QR code and reconstructed QR code were identical.