This paper proposes a new chaotic system based on sine map, i.e., the coupled piecewise sine map (CPSM), which utilizes piecewise mechanism to obtain more uniform probability density distribution of state values, and enhances the complexity of chaotic system by coupling parameters between sub-systems. Then, from the view of resisting the chosen ciphertext attack, a ciphertext sensitive diffusion structure is presented. Based on the CPSM and the ciphertext sensitive diffusion structure, this paper proposes a new image encryption algorithm. Since the CPSM can generate chaotic sequences with good cryptographic properties and the diffusion structure has good diffusion performance in both the encryption process and the decryption process, the proposed encryption algorithm is extremely sensitive to the ciphertext tampering. Thus, it can effectively resist the chosen ciphertext attacks. Experimental results and security analysis also confirmed that the proposed algorithm has good security and can ensure the secure transmission of image in the Internet.

本文提出了一种新的基于正弦图的混沌系统，即耦合分段正弦图（CPSM），它利用分段机制获得更均匀的状态值概率密度分布，并通过子节点之间的耦合参数提高混沌系统的复杂度。 -系统。然后，从抵抗选择密文攻击的角度，提出了一种密文敏感扩散结构。基于CPSM和密文敏感扩散结构，本文提出了一种新的图像加密算法。由于CPSM可以生成具有良好密码特性的混沌序列，并且扩散结构在加密过程和解密过程中都具有良好的扩散性能，因此所提出的加密算法对密文篡改极为敏感。因此，它可以有效地抵抗选定的密文攻击。实验结果和安全分析也证实了该算法具有良好的安全性，可以保证图像在互联网上的安全传输。