Image encryption algorithm based on exponential compound chaotic system

Aiming at the problems of existing image encryption algorithms based on chaotic systems, such as weak resistance to differential attacks and unstable performance of chaotic systems, an image encryption algorithm based on exponential composite chaotic systems was proposed.The algorithm first inserted random values into the R, G and B components of the image, and iteratively outputted chaotic vectors from the improved exponential compound chaotic system to form a scrambling matrix, scrambling the pixels of the plaintext image.Then the chaotic matrix output by the chaotic system iteratively and the plaintext pixel matrix were used to realize the diffusion by modular operation.Finally, the ciphertext image was obtained by matrix transformation of encryption matrix of three components of R, G and B, which was controlled by the secret key and chaotic sequence.The results show that the algorithm has a large key space, and ciphertext information entropy, number of pixel change rate (NPCR) and uniform average change intensity (UACI) are all close to ideal values.It has strong resistance to differential attacks and high security performance. © 2021, Editorial Board of Journal of Huazhong University of Science and Technology. All right reserved.