Fast selective encryption algorithms based on moments and chaos theory

In this work, we introduce a novel selective encryption scheme based on chaos theory and moments transforms, two moments families were considered namely Tchebichef and Hahn. The goal is to propose a fast and secure encryption scheme that can be deployed in real world scenarios. The proposed algorithms operate in the transform domains of Tchebichef and Hahn moments. We encrypt only the most significant coefficients of the moments transforms. First, we down sample the computed moments’ matrices coefficients, then we use two logistic maps for confusion and diffusion of the down-sampled Tchebichef’s and Hahn’s coefficients, the resulting matrix is the encrypted image. This approach improves drastically the time performance of the encryption algorithm while keeping a “good” security level. In order to prove the performance of our algorithms, we run different experiments and test the algorithms on different criteria: MSE, correlation coefficient, differential analysis, entropy and time performance. The presented results prove that the encryption algorithms proposed are secure and outperform state-of-the-art algorithms.