chaotic image encryption method based on three-dimensional nonlinear system

 Due to the simple structure of one-dimensional chaotic mapping, there may be problems such as lack of security in applying to image encryption; so many researchers have proposed some high-dimensional chaotic mapping to apply to image encryption. However, high-dimensional chaotic mapping may be difficult to be applied in practice because of its complex structure and high cost. So this paper proposes an image encryption method with a relatively simple structure, low cost, and good encryption effect. The Proposed method combines a chaotic system with 3D nonlinear function iterative systems to encrypt images. First, a sequence is generated iteratively according to the given chaotic system, and then the sequence is used to call multiple three-dimensional nonlinear function systems in the group and perform operations in turn; then the iterative operations are performed according to the image size; finally, the chaotic sequence generated by the iteration and the grayscale image is subjected to an XOR operation. The phase diagram and bifurcation diagram determine the iterative sequence to have chaotic solid properties. The algorithm performs only a simple XOR operation, but the experimental results show the scheme is feasible.