基于交叉耦合映像格子的图像加密方案的设计

Design of Image Encryption Scheme Based on Cross Coupled Map Lattice

交叉耦合映像格子是一种用于描述时空系统混沌状态的模型,基于交叉耦合映像格子的混沌特性提出了一种新颖的图像加密方案,用Chebyshev映射提供交叉耦合映像格子的初值,并用所产生的时空混沌序列值对原图像进行迭代和置乱处理,经发送方发送,通信双方同步后,接收方通过解密方案得到相应的解密图像,实现了图像的保密通信.方案的密钥空间较大,因此具有较高的安全保密特性,同时对初值的高度敏感性提高了加密方案的抗攻击能力.仿真结果验证了方案的可行性,并且体现了应用在图像加密中的交叉耦合映像格子算法的有效性和优越性.

A novel image encryption scheme is proposed based on the chaotic feature of cross CML （coupled map lattice） which is a model for describing the chaotic states of spatiotemporal systems. The scheme uses Chebyshev mapping to provide the initial value of cross CML and utilizes the generated spatiotemporal chaos sequences to encrypt source image by the process of iteration and permutation. After the encryption image is sent from the sender, the receiver will receive the image decrypted by the decryption scheme once the communication is synchronized, which realizes the secure communication of the image. The scheme has the property of high security because its key space is large, and the high sensitivity to the initial value enhances the anti-attack ability of the encryption scheme. The simulation results show that the scheme is feasible and that the cross CML algorithm used in image encryption is effective and superior.