Chaos-Based Image Encryption Using Circular Bitwise Rotation and XOR for Enhanced Confusion and Diffusion

This study introduces a proficient encryption technique for digital images, employing pseudo-random numbers generated through a chaotic nonlinear function. The chaotic Henon map based secret keystreams matrix are generated through a sequence of intricate mathematical calculations. The incorporation of these secret key values with inventive concepts is responsible for implementing the confusion and diffusion properties. The diagonal scan methodology is employed to transform the original image matrix into a partial cipher. A newly introduced method utilizes a keystream generated from the chaotic Henon map for bit level scrambling of the partial cipher image. Security in image permutation is bolstered by implementing scrambling both at the pixel and bit levels. Decryption is achieved by applying the converse of the encryption concept, yielding high-quality reconstruction results. The performance of the envisioned cryptosystem is assessed using a range of evaluation metrics. A comprehensive comparison of the developed approach against cutting-edge techniques highlights the superior security and dominance of the proposed system.