This article proposed an improved 2D-logistic-adjusted-Sine map, which has better ergodicity, pseudo-randomness, unpredictability and wider chaotic range than many existing 2D-chaotic maps. Utilizing improved 2D-logistic-adjusted-Sine map generates chaotic sequences, where the initial values of the system are assigned based on SHA 512 hash function. Compared with traditional encryption scheme, the size of cipher image is different to plain image, because multiply can be applied between mismatched dimensional matrices through semi-tensor product, and therefore, attackers cannot obtain the size of plain image from encryption image. In order to lighten transmission and storage burden, we reduce the results of semi-tensor product by data process. Keys security, correlation coefficient, information entropy and ability of defending differential attack are analyzed to confirm the security of our encryption scheme. Experimental results confirm that the proposed algorithm can encrypt image effectively and securely.

本文提出了一种改进的2D-logistic-adjusted-Sine图，它比许多现有的2D-混沌图具有更好的遍历性、伪随机性、不可预测性和更宽的混沌范围。利用改进的 2D-logistic-adjusted-Sine 映射生成混沌序列，其中系统的初始值基于 SHA 512 哈希函数分配。与传统加密方案相比，密码图像的大小不同于明文，因为可以通过半张量积在不匹配的维矩阵之间进行乘法运算，因此攻击者无法从加密图像中获得明文的大小。为了减轻传输和存储负担，我们通过数据处理来减少半张量积的结果。密钥安全性、相关系数、分析信息熵和防御差分攻击的能力，以确认我们的加密方案的安全性。实验结果表明，该算法能够有效、安全地对图像进行加密。