Multi-layered covert QR codes for increased capacity and security

摘要

Quick Response (QR) codes, used in marketing, warehouse management, product tracking, and other applications, are usually only comprised of visible black and white modules. The goal of this research is the creation of covert, color QR codes for increased data capacity, and security. This goal was met by layering QR codes, each of a unique color, printing the covert versions of the color QR codes, upconverting the covert codes into visible codes and unlayering them to take advantage of the various color channels present. It was shown that color layering of the QR codes effectively increased the data capacity by three times that of a traditional QR code, while the covert nature of the code provides added security. Finally, it was also demonstrated that a layered QR code with six base colors (using color intensity variations) could further increase QR code data capacity.