A chaotic permutation and diffusion based image encryption algorithm for secure communications

In this digital era, a huge amount of digital data is being generated, transmitted, and stored over the network. Images are widely searched, shared and uploaded which make them more vulnerable to the attackers. Therefore, image encryption has become the most widespread form of secure image communication. In recent past, a range of chaotic encryption schemes have been proposed for image encryption which suffers from low key space and high computational overhead. In this paper, the authors have proposed a secure image encryption technique based on 2D Baker's map. In the proposed scheme a plain image is permuted first, based on a sequence of pseudo random number generated by 2D Baker's map followed by diffusion process based on XORing. The strength of the proposed scheme is analyzed using the most well-known security test measures like NPCR, MSE, PSNR, UACI, correlation coefficient, Entropy etc. and the results demonstrate that the proposed scheme is resistive to various types of known attacks. The scheme runs on comparatively low computational overhead. Further, the results are compared with existing schemes.