New Chaotic Permutation Methods for Image Encryption

International audienceSince two decades, and in order to reach higher performance, more and more studies look to combine the conventional encryption methods and the complex behaviour of chaotic signals. To quantify the expected improvement induced by such a mix, this paper aims to compare the performance of two well known chaotic maps, namely, Logistic and piecewise linear chaotic map with their performance when they are perturbed by a new technique. These four chaotic maps are then used to control three bit permutation methods: Grp, Cross and Socek, known to have good inherent cryptographic properties. When applied to images, the common measures like NPCR, UACI, intra and inter-components correlation coefficients, histogram and distribution of two adjacent pixels lead to two main results. First, Socek permutation method remains better than Grp and Cross whatever the used chaotic map. Second, the proposed chaotic permutation methods controlled by the perturbed maps present higher performance and is more secure and suitable for chaotic image encryption scheme