This study proposes a novel image encryption algorithm based on a two-dimensional discrete chaotic system that integrates cellular automata (CA) with a tent map. The algorithm addresses security vulnerabilities in digital image transmission and storage across open networks or cloud environments. It employs a three-phase encryption process: coordinate permutation, spatial permutation, and diffusion. Sequential application of Arnold’s coordinate scrambling, maze traversal-based spatial rearrangement, and a CA-driven diffusion mechanism enhances robustness against noise, differential attacks, and partial cropping. A Dynamic CA–Tent Map (DCA–TM) hybrid chaotic system is designed to overcome periodicity and limited key space issues inherent in conventional chaotic encryption. The permutation stage is refined into coordinate and spatial phases to achieve comprehensive pixel randomization. During diffusion, CA rules are selected dynamically based on the iteration counts of the initial parameters, yielding an adaptive encryption system with a variable key space. Performance evaluations—including Lyapunov exponent tests, bifurcation analysis, information entropy measurement, and pixel correlation assessment—confirm the strong chaotic behavior and high security of the proposed scheme.
Huang et al. (Thu,) studied this question.