In this paper, single and multiple S-box encryption issues are discussed and a new algorithm is then proposed to solve those issues. As the single S-box encryption completely fails to encrypt the plain image because a single S-box replaces the pixels of the same region with a unique symbol. To break this type of correlation in the image, chaos has been extensively used. The multiple S-boxes techniques are becoming more popular over the last decade to overcome the drawbacks of single S-box encryption. However, replacing single S-box with multiple S-boxes is somehow good for the encryption of those images which contain more number gray levels i.e 256 gray levels, but it cannot properly conceal the pixels of an image having less number of gray levels i.e binary or plain white images which contain only one gray level. To solve these issues, a dynamic substitution based encryption algorithm (DSA) is proposed, which is specially designed for the highly correlated images. Security analysis and evaluation show that the proposed algorithm can accomplish to conceal the highly correlated data.

中文翻译：

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基于动态替换的高相关数据加密算法

在本文中，讨论了单个和多个 S 盒加密问题，然后提出了一种新算法来解决这些问题。由于单个 S-box 加密完全无法加密纯图像，因为单个 S-box 用唯一符号替换了同一区域的像素。为了打破图像中的这种相关性，混沌已被广泛使用。在过去的十年中，多 S 盒技术变得越来越流行，以克服单 S 盒加密的缺点。然而，用多个 S-box 替换单个 S-box 在某种程度上对那些包含更多灰度级（即 256 个灰度级）的图像的加密有好处，但它不能正确隐藏灰度级数较少的图像的像素，即二进制或仅包含一个灰度级的纯白色图像。为了解决这些问题，提出了一种基于动态替代的加密算法（DSA），该算法专门针对高度相关的图像而设计。安全性分析和评估表明，该算法可以实现对高度相关数据的隐藏。