Dynamic DNA cryptography-based image encryption scheme using multiple chaotic maps and SHA-256 hash function

Abstract

In today's world, a substantial number of digital images are conserved and transmitted through diverse online platforms on a daily basis. Preserving the confidentiality of images is a paramount issue in the current digital environment. To safeguard the privacy of digital images on internet platforms, a robust, effective, and reliable encryption technique is required. This paper proposes a robust and efficient image encryption scheme based on a dynamic DNA encoding and DNA operations associated with chaotic maps with simple structures and highly chaotic behavior, such as the Logistic map, the Henon map, and the Lorenz system, to provide substantial security for digital images. Furthermore, the SHA-256 hash technique and zigzag traversal are used in the algorithm to reinforce the system. This paper defines an improved DNA encoding scheme that can encode four bits at once instead of two bits. Besides, unique and randomized keys are generated for each encryption and decryption session. The proposed scheme exhibits several admirable characteristics, including low processing cost, high randomness, large key space, flexible parameter space, high sensitivity to both keys and plaintext, and fast execution speed. As a result, the proposed scheme effectively safeguards sensitive digital images from a broad range of cryptographic attacks. Numerous evaluation results have demonstrated that the proposed algorithm is more secure and efficient than state-of-the-art methods against a huge assortment of cryptographic attacks.