目的 针对Arnold映射图像置乱效果差以及无法抵御选择明文攻击等问题，提出一种改进广义Arnold映射的图像加密算法，以提高密文图像的安全性。方法 该算法引入Kent映射产生控制参数，先对图像进行分块来削弱图像的相关性，对每块图像进行Arnold映射位置置乱，然后利用二维logistic映射生成混沌序列，经双曲正切变换处理后按照奇偶序列与置乱图像进行异或运算，得到最终密文图像。结果 该算法得到密图信息熵为7.9899，像素改变率为99.61%，统一平均变化程度为30.73%。结论 该算法简单易执行，能有效抵御各种统计攻击和明文攻击，具有密钥空间大、置乱效果好、鲁棒性较强等特点。

The work aims to propose an image encryption algorithm based on improved generalized Arnold mapping to improve the security of the encrypted image regarding the problem that the image scrambling effect of Arnold mapping is poor and the chosen plaintext attack cannot be resisted. The algorithm introduced Kent mapping to generate control parameters. First, the images were partitioned to reduce the image correlation. Each image’s Arnold mapping position was scrambled. Then the 2D logistic mapping was used to generate chaotic sequences. Through the hyperbolic tangent transformation processing, XOR was conducted according to the parity sequence and the scrambled images, and the final ciphertext image was obtained. The information entropy of the ciphertext image obtained through the algorithm was 7.9899, the pixel change rate was 99.61%, and the uniform average change degree was 30.73%. The algorithm is simple and easy to implement. It can effectively resist all kinds of statistical attacks and plaintext attacks. It is also characterized by large key space, good scrambling effect and strong robustness, etc.