针对光学多图像认证方法中,多路复用图像中的串扰噪声,以及不同认证级别下的信息安全问题,提出了一种基于超混沌振幅型掩模和Gyrator变换域下相位信息复用的光学多图像认证方法。利用分数阶超混沌Rabinovich系统构造超混沌随机振幅掩模;基于改进的Gerchberg-Saxton算法对原始图像进行低级或高级编码,利用超混沌掩模作为振幅约束,迭代获得目标图像,并将得到的N个目标图像编码成复合图像;再次通过Gerchberg-Saxton迭代将复合图像转化为两个便于传输的纯相位掩模。实验结果表明:在认证过程中,不同安全级别的用户拥有各自的认证密钥,低级认证过程中可以通过检索图像与原始图像的非线性相关峰值,判断认证图像的正确性,而高级认证过程中则可以获得与原始图像相似度较高的认证图像,峰值信噪比和相关系数分别可达25.2817 dB和0.9844。所提方法对遮挡攻击和噪声攻击具有良好的稳健性,为多幅图像在不同级别下的光学认证提供了新的思路。

This study proposes an optical multiimage authentication method for attenuating crosstalk noise in multiplexed images and addressing information security problems at different authentication levels based on hyper-chaotic amplitude masks and phase information multiplexing in the Gyrator transform domain. According to the proposed method, hyper-chaotic random amplitude masks are constructed first using a fractional hyper-chaotic Rabinovich system. Then, original images are encoded using a modified Gerchberg-Saxton algorithm for low- and high-level authentication. The hyper-chaotic masks are used as the amplitude constraint to iteratively obtain target images. The obtained N target images are then encoded into a composite image. Finally, the composite image is converted into two phase-only masks for transmission using the modified Gerchberg-Saxton algorithm. Results demonstrate that users can have their own authentication keys in the process of authentication at different security levels. In low-level authentication, the correctness of the authentication image can be determined by retrieving the nonlinear correlation peak between the authentication and original images. In high-level authentication, the authentication image can be obtained to be highly similar to the original image with the peak signal-to-noise ratio and correlation coefficient reaching 25.2817 dB and 0.9844, respectively. The proposed method is robust against occlusion and noise attacks and provides a new idea for optical authentication of multiple images at different levels.