Image encryption algorithm based on pseudorandom sequences generated by hyperchaotic systems

This paper proposed an efficient image encryption algorithm in which hyperchaotic systems are used to generate the pseudorandom sequences. The algorithm was composed of two stages, i.e., permutation and diffusion. First, the sorted hyperchaotic sub-sequences were used in the permutation stage. It can substantially reduce the correlation between adjacent pixels. Then, in the stage of diffusion, double diffusion functions were utilized with a novel generation of the keystream. The proposed method can resist known-plaintext and chosen-plaintext attacks due to the keystream depends on the processed image. Experiment results and security analysis not only show that the scheme can achieve good encryption result, but also that the encryption and decryption are performed in a fast manner.