Distributed three-level QR codes based on visual cryptography scheme

Abstract

Owing to the large storage and fast machine recognition, QR codes have been widely utilized in many fields such as mobile payment, website navigation and user identity authentication. However, any QR code reader can access to the message contained in the QR code, the security becomes a major challenge to QR codes for privacy usage scenarios. Moreover, the management of QR codes for users are also inconvenient, since the human vision is hard to distinguish a QR code from the others. To solve the security and management problems, we propose the three-level QR codes for a group of participants. The first-level management information and the second-level public information are recognizable for the human vision and QR code reader device, respectively. The third-level privacy information is protected using visual cryptography scheme, and can be decoded using simple and non-cryptography computations. Furthermore, the shares can be stored or transferred in not only e-format but also print-format and photo-format, leading to the broad applicability. Experimental results and analysis demonstrate that the proposed scheme can encode three-level information into several distributed QR codes, and has more advantages compared with the previous schemes.