Arnold Image Scrambling

Arnold image scrambling MATLAB code -------------------------------------------------------------------- Function: Arnold Image Scrambling Transformation: x = (x + y) mod N, y = (x + 2y) mod N Transformation periods (N, M): (128, 96), (256, 192), (512, 384) Parameters: - dPSNR: PSNR after scrambling (controls scrambling intensity) - outImg: Output image after scrambling - inImg: Input image - iTimes: Number of scrambling iterations Version: 1.01.20070409 -------------------------------------------------------------------- Arnold image scrambling is a pixel permutation algorithm that rearranges image pixel positions through mathematical transformations. The core algorithm implements Arnold transformation using two mathematical formulas for coordinate scrambling. The transformation period can be customized, with common configurations being (128, 96), (256, 192), and (512, 384). Beyond period adjustment, scrambling intensity can be controlled through post-scrambling PSNR values. The scrambled image is saved as output, and the scrambling operation can be repeated multiple times through specified iteration counts. This implementation uses modular arithmetic to ensure coordinates wrap around image boundaries properly. Key implementation details: - The algorithm processes pixel coordinates through iterative Arnold transformations - Modular arithmetic (mod N) ensures coordinates remain within image dimensions - Multiple iterations enhance scrambling effect through compounded transformations - PSNR calculation provides quantitative measure of scrambling intensity - The code handles different image sizes through configurable period parameters