基于分数阶傅里叶变换的光学加密影片

随着通信与网络的快速发展,能够包含大容量信息的影片得到了广泛应用。利用分数阶傅里叶变换的特点,提出了一种全光学加密解密影片的方法。将现有的影片加密密钥从二重变为了四重,显著增加了影片的安全性。通过改变振幅型正弦光栅的作用位置,将影片的加密解密次数由现有的每帧各一次减小为总共一次,优化了算法。仿真结果验证了该方法的有效性。

All-optical encrypted movie based on fractional Fourier transform

With fast developments of communications and internets, movies containing huge information are widely used. An optical encryption/decryption method based on fractional Fourier transform is proposed. The method increases number of the encryption keys for an all-optical encrypted movie from two to four. The security level of the all-optical encrypted movie is enhanced greatly. The interaction site of the amplitude sinusoidal grating is optmized. Encryption and decryption are needed once for a whole movie in the proposed method rather than for every frame of the movie in the previous methods. The implementation of the method is significantly simplified. The effectiveness of the method is verified with simulations.