Image encryption algorithm based on a new 2D polynomial chaotic map and dynamic S-box

Due to its amplification effect on the deviation of the initial value, chaotic systems have been closely integrated with image encryption in the past few years, which inspires the research of many image encryption algorithms. The S-box has become the core ingredient of various encryption scheme because of its nonlinearity, and is the foundation of the security performance. Hence, it is attractive to use chaotic maps to build high-performance and efficient S-boxes. In this study, a new 2D discrete hyperchaotic map is introduced, chosen for its holistic advantages over the conventional 2D hyperchaotic map. It serves as a vital element in a more robust encryption scheme. The proposed chaotic map is applied to the process of building the base S-box, and obtain 8 dynamic S-boxes on their combination. Through experimental analysis, it can be concluded that the S-box constructed has higher encryption advantage and has strong resistance to various security attacks. Then, the elements of the plain image are scrambled by selecting the independent S-box through modulo operation. Last step, using the built PRNG to generate cipher images. Analysis of experimental data indicates that the proposed image encryption scheme surpasses comparable chaotic image encryption schemes and is capable of withstanding common security threats.