Color Image Encryption Algorithm Based on High Dimensional Combination Chaotic System and DNA Coding

In order to solve the problem of limited key space and simple chaotic behavior of a single chaotic system, a high dimensional combined chaotic system model based on cosine transform is proposed. By combining one dimensional chaotic systems with weights, the output results are coupled by cosine transform, and then the corresponding high dimensional combined chaotic system is obtained. A color image encryption algorithm based on high-dimensional combined chaotic system and DNA encoding is designed according to the proposed high-dimensional combined chaotic system. The algorithm first uses the sequence value generated by the high-dimensional combined chaotic system to scramble the plaintext image at the bit and pixel levels. Secondly, DNA encoding technology is used to perform dynamic DNA operation on the scrambled image. Finally, the nonlinear component S-box is used to replace pixel values, which further improves the security of the algorithm. The simulation results show that the combined chaotic system has larger key space and better chaotic behavior, and the color image encryption algorithm based on high dimensional combined chaotic system and DNA can resist various common attack methods and has better security.