A Survey and Analysis of the Image Encryption Methods

摘要

At the present time, the protection of multimedia data has become a very important process which can be achieved by encryption. Basically, so many different techniques have been used to protect private image data from those who illegally try to have access. An efficient cryptographic scheme is one that has a space of a large key that resists brute force search time, less execution time complexity/Highspeed and should be able to provide high confusion and diffusion for good security. In this paper, we survey an existing work which uses classic and modern techniques for image encryption, as the classic techniques used for text based on alphabets as basic elements while the modern techniques overcome this limitation by used mathematical algorithms for coding the information due to their digital system. A comparison has been conducted between several ciphers techniques (classic and modern) for images based on various parameters such as: Histogram, Correlation, Number of Pixels Change Rate (NPCR), Unified Average Changing Intensity (UACI), Peak Signal to Noise Ratio (PSNR), Entropy and Time complexity. An analysis of simulation result shows that chaotic encryption technique especially hyper-chaotic is the most efficient among the all.