Color image encryption scheme based on 5D fractional-order complex chaotic system and eight-base DNA cubes

Abstract

With the rapid development of information technology, the secure transmission of color images has become an urgent problem. In order to overcome this problem, this paper proposes a high-security color image encryption algorithm. First, a five-dimensional fractional-order complex chaotic system is designed, and its dynamics are comprehensively analyzed from the perspectives of Lyapunov exponent spectrum, bifurcation diagram, and phase diagram. The results prove that the system has good chaotic characteristics. Second, a dynamic Arnold scrambling algorithm is designed, which dynamically generates scrambling parameters by calculating the pixel values of each channel of an image. Then, combined the eight-base DNA coding scheme with a three-dimensional cube structure, a space rotation-based scrambling method and a diffusion method integrating DNA mutation and crossover operations were designed under chaotic sequence control, thereby enhancing the nonlinearity and security of the encryption system. Finally, simulation experiments and security analysis indicate that the proposed color image encryption scheme provides high security and strong key sensitivity. It effectively scrambles pixel distributions, demonstrating robustness against statistical, noise, and cropping attacks, while maintaining efficient computational performance. These results demonstrate its effectiveness for secure digital image transmission.