QR Code Digital Watermarking Algorithm Based on Two-Dimensional Logistic Chaotic Map

QR (Quick Response) codes, originally designed to facilitate tracking parts in automobile manufacturers, have been increasingly widely used in various fields, and gradually become an indispensable tool in people’s lives. However, with the development of network and multimedia technology, the pure QR code cannot effectively resist the two-dimensional code forgery and tampering attacks. Aiming at this shortcoming of QR code, this paper introduces digital watermarking technology into the protection of QR code image and proposes a digital watermark anti-counterfeiting algorithm based on QR code binary image. According to the characteristics of the QR code binary image, the algorithm combines the MD5 (Message-digest Algorithm 5) encryption algorithm and the two-dimensional logistic chaotic mapping algorithm to embed the watermark, which improves the security of the QR code based on the correct identification. Experimental results show that the watermarking algorithm has strong concealment, robustness, and large watermark capacity.