Initial-boosted dynamics in a memristive Chialvo map and its application for image encryption with hardware implementation

Abstract

Generally speaking, the discrete map possesses a low dimension and complex dynamics that can trigger hyperchaos to apply in image encryption. In this paper, we lead a memristor possessing cosine mem-conductance into the one-dimensional (1D) Chialvo map by sinusoidal-modulation-input method, thereby a two-dimensional (2D) memristive Chialvo (m-Chialvo) map is constructed. The fixed points stability and the forming mechanism for initial-boosted behavior are theoretically deduced. Numerical simulations show that the 2D m-Chialvo map can trigger initial-boosted hyperchaotic attractors, which hold the availability for image encryption. Besides, an FPGA-based digital platform is implemented to offer the verification of the initial-boosted hyperchaotic attractors. Furthermore, an STM32-based image encryption algorithm with hardware implementation is designed by deploying the coexisting hyperchaotic sequences, and the encrypted images can pass various performance tests. This verifies the feasibility of the hyperchaotic sequences for the algorithm in STM32-based image encryption with hardware implementation.