Abstract: A new image encryption method based on rotation transformation and chaos theory was proposed, which used chaos function to generate random phase mask (chaotic random phase mask). In the proposed technique, the image was encrypted using gyrator transform and two chaotic random phase masks. In the proposed method, the image was encrypted by using rotation transform and two chaotic random phase masks, and the chaotic random phase mask was generated by using three chaotic functions: Logistic map, Tent map and Kaplan⁃Yorke map. The computer simulations were presented to verify the validity of the proposed technique. By calculating the mean square deviation, the robustness of the blind decryption algorithm based on the seed value of rotation angle and chaotic random phase was evaluated, and the optical implementation scheme of encryption and decryption technology was given.

Key words: Image encryption/decryption, Gyrator transform, Logistic map, Tent map, Kaplan?Yorke map, Mean square error

摘要： 提出了一种利用旋转变换和混沌理论进行图像加密的新方法。使用旋转变换和两个混沌随机相位掩膜对图像进行加密，利用Logistic映射、帐篷映射和Kaplan⁃Yorke映射三种混沌函数产生混沌随机相位掩膜。通过计算均方差，基于旋转角和混沌随机相位的种子值的盲解密算法的鲁棒性进行了评估，并给出了加密和解密技术的光学实现方案。结果表明，利用所提方法进行图像加密的有效性。

关键词: 图像加密/解密, 旋转变换, Logistic映射, 帐篷映射, Kaplan?Yorke映射, 均方差