Color image encryption using a Zigzag Transformation and sine–cosine maps

This research endeavor is dedicated to enhancing data confidentiality in internet transmissions by strategically employing Hash functions and harnessing the advantageous attributes of chaos. These attributes, characterized by inherent complexity, sensitivity to initial conditions, and resilience to attacks, are foundational elements in the realm of image encryption. The proposed encryption algorithm firmly adheres to the principles of confusion and diffusion, thereby constructing a secure framework. Within the permutation phase of the algorithm, a meticulously crafted scrambling technique takes center stage. This technique adeptly disperses adjacent pixels within an image across the red, green, and blue channels through both horizontal and vertical zigzag transformations. This intricate process significantly elevates the level of intricacy and unpredictability within the encryption procedure, bolstering security measures. To further fortify security, the substitution stage integrates two one-dimensional chaotic systems, specifically 1-DSP and 1-DCP. These systems serve as mechanisms to introduce subtle alterations to the original image, affecting all pixels within the encrypted image. The extent of these alterations hinges on the values of the three least significant bits (LSB) of each pixel. The incorporation of this dual chaotic system approach introduces an additional layer of complexity and security into the encryption methodology. The effectiveness of the proposed system is subjected to rigorous evaluation through a comprehensive security analysis. This analysis encompasses an array of performance metrics, including NPCR (Normalized Pixel Change Rate), UACI (Unified Average Changing Intensity), correlation coefficient, histogram analysis, and key sensitivity analysis. These metrics collectively serve to assess the viability and feasibility of the suggested approach, functioning as a litmus test for the system's resilience and efficiency. The results of this evaluation underscore the robust security and superior performance of the proposed image encryption method, positioning it favorably when compared to various advanced image encryption algorithms.