A Novel Color Image Encryption Scheme Based on Fractional-order Chaotic System

This paper proposes a color image encryption scheme based on fractional-order chaos. The characteristics of the fractional-order chaotic system are first explored and its dynamic behaviors are analyzed, then it is combined with Discrete Wavelet Transform (DWT) and DNA coding techniques to design a high-performance encryption scheme. The image encryption scheme divides the input image into its four frequency bands using DWT. DNA encryption is only applied to the low frequency, reducing encryption time. Random sequences generated by chaotic systems are used in processes including DNA sub-band encryption, global scrambling, diffusion, and block rotation. Finally, the simulation results demonstrate that the scheme has the excellent security and confidentiality to resist common cryptographic attacks. The proposed scheme is deemed a promising approach for protecting the privacy of digital images.