Abstract This study designs a novel image encryption cryptosystem through the two-dimensional partial unwinding decomposition (2D-PUD). It consists of three stages. Firstly, a stream sequence (first part of the security key) is generated by pseudo-random number. Secondly, the plain image is decomposed into three parts by 2D-PUD: one 2D decomposition component, two 1D decomposition components, and the average intensity value of the image. Finally, the 2D decomposition component is shuffled by a generalized Arnold transform where the average intensity value is selected as second part of the security key. The diffusion scheme is subsequently applied to the scrambled image via exclusive OR operations with the randomized 1D decomposition components (third part of the security key) along rows and columns to obtain the cipher image. Due to the adaptive attribute of 2D-PUD, the generated 1D decomposition components are completely distinct for different images. In addition, we can also make them significantly different by tuning the decomposition times for the same image. Thus, the proposed algorithm is an image-content-adaptive encryption scenario that can effectively resist cryptographic attacks. Simulation results demonstrate that our proposed method has excellent encryption performance and can resist against various typical attacks, including brute force, statistical, entropy, and differential attacks.

中文翻译：

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具有部分展开分解的内容自适应图像加密

摘要 本研究通过二维部分展开分解（2D-PUD）设计了一种新颖的图像加密密码系统。它由三个阶段组成。首先，通过伪随机数生成流序列（安全密钥的第一部分）。其次，将普通图像通过 2D-PUD 分解为三个部分：一个 2D 分解分量，两个 1D 分解分量，以及图像的平均强度值。最后，二维分解组件通过广义阿诺德变换进行混洗，其中选择平均强度值作为安全密钥的第二部分。扩散方案随后通过与随机化的一维分解组件（安全密钥的第三部分）沿行和列的异或运算应用于加扰图像，以获得密码图像。由于 2D-PUD 的自适应属性，生成的 1D 分解分量对于不同的图像是完全不同的。此外，我们还可以通过调整同一图像的分解时间来使它们显着不同。因此，所提出的算法是一种图像内容自适应加密场景，可以有效抵抗密码攻击。仿真结果表明，我们提出的方法具有出色的加密性能，可以抵抗各种典型的攻击，包括蛮力攻击、统计攻击、熵攻击和差分攻击。所提出的算法是一种图像内容自适应加密场景，可以有效抵抗密码攻击。仿真结果表明，我们提出的方法具有出色的加密性能，可以抵抗各种典型的攻击，包括蛮力攻击、统计攻击、熵攻击和差分攻击。所提出的算法是一种图像内容自适应加密场景，可以有效抵抗密码攻击。仿真结果表明，我们提出的方法具有出色的加密性能，可以抵抗各种典型的攻击，包括蛮力攻击、统计攻击、熵攻击和差分攻击。