تحليل و پياده سازي الگوريتم رمزنگاري تصوير مبتني بر مربع لاتين

The Analysis an‎d Implementation of Latin Square Image Encryption Algorithm

رياضي كاربردي و علوم كامپيوتر

Digital images are among the most common an‎d widely used multimedia data in the era of big data. With the rapid development of information an‎d communication technologies, the security of image data has gained increasing importance. Image encryption plays a critical role in protecting visual data against unauthorized access an‎d ensuring privacy. This thesis initially implements, analyzes, an‎d examines an image encryption algorithm based on the Latin square. The algorithm consists of two phases: permutation an‎d diffusion. In the permutation phase, row an‎d column permutations based on the Latin square rearrange the pixel positions, significantly reducing the strong correlation between neighboring pixels in the image. In the diffusion phase, the brightness level of each pixel is altered using the Latin square, resulting in a uniform histogram for the encrypted image an‎d enhanced algorithm security. In the second part, an image encryption algorithm based on fractal sorting matrices an‎d chaotic functions is implemented, analyzed, an‎d examined. In this algorithm, three chaotic sequences are first generated using an encryption key. During the permutation phase, a fractal sorting matrix is created using the first chaotic sequence to rearrange pixel positions in the image. Then, in the diffusion phase, the brightness levels of image pixels are modified using the second an‎d third chaotic sequences. Finally, the performance an‎d security of these two image encryption algorithms are eva‎luated through metrics such as key space analysis, key sensitivity, histogram analysis, correlation coefficient analysis, an‎d resistance to differential, cropping, an‎d noise attacks.

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