Design of a new four-dimensional chaotic system and its application to color image encryption

Abstract

In this paper, a new four-dimensional chaotic system is constructed. Then, the dynamics of the phase diagram, Lyapunov exponent, bifurcation, and complexity of the system are investigated, the simulation circuit of the system is designed and the trajectory simulation of the system is implemented using a Field Programmable Gate Array (FPGA). National Institute of Standards and Technology (NIST) tests have verified the randomness of the output of the chaotic sequence by the system. Finally, a new color image encryption algorithm is designed based on this system. In the proposed algorithm, the plaintext information is used to generate the initial value of the system through a hashing algorithm, and the plaintext information is applied to the algorithm, reflecting the idea of algorithmic adaption. The bit-plane decomposition row dislocation breaks the strong correlation between pixels, and finally, the DNA encoding is combined with the diffusion method to complete the complete encryption process. Multiple security analysis methods show that the scheme has a good encryption effect.