An image encryption scheme using dynamic S-boxes

Abstract

This paper proposes a chaos-based image encryption scheme using modified standard map. The scheme has two stages: the confusion stage in which pixel permutation and dynamic s-box substitution scrambles the image and modifies the pixel values; the diffusion stage, where diffusion is carried out in a random pattern. A chaotic key sequence is generated using the modified standard map. The scheme is designed to be dependent on this chaotic sequence. Analysis using entropy, histogram, correlation, NPCR and UACI values shows that the modified standard map together with dynamic s-box substitution makes the scheme strong and secure against statistical and differential attack.