A new technique for designing 8 × 8 substitution box for image encryption applications

Abstract

To create confusion in ciphertexts, encryption processes depends upon nonlinear mappings. This nonlinear mapping can be achieved by a process known as substitution. In a secure encryption algorithm, substitution plays a key role during confusion stage of encryption algorithms. In this work, we present a novel chaos-based substitution box that can be utilized in the encryption processes for securing digital images from eavesdroppers. The proposed substitution box is also compared with other conventional substitution boxes presented in literature. Various statistical measures such as contrast, correlation, energy and homogeneity analysis prove the superiority of the proposed substitution box.