A Novel Plaintext-Related Image Encryption Scheme Based on Chaotic System and Pixel Permutation

To improve the abilities of image encryption systems to resist plaintext attacks and differential attacks, a novel plaintext-related image encryption scheme based on Josephus traversing and pixel permutation is proposed. In this scheme, the step sizes of the Josephus traversing are associated with the pixel values, and the Josephus traversing method is improved, increasing the dependence of the cipher image on the plaintext image, further enhancing the plaintext sensitivity of the algorithm, and reducing the number of iterations of the index sequence generated by the chaotic system. By segmenting the image and combining a chaotic system, bit XOR and crossover operations between the modules are performed to achieve the effects of confusion and diffusion, and the randomness of the cipher image is improved. Finally, the confusing and spreading characteristics of the algorithm are further enhanced by cipher feedback. The experimental results and security analysis show that the proposed algorithm is sensitive to keys and can effectively resist attacks such as statistical attacks, selective-plaintext attacks and exhaustive attacks. The algorithm has high potential for real-time and secure image applications.