基于矢量分解和相位截取Gyrator变换的图像加密

为了提高光学图像加密系统的安全性,采用了矢量分解和相位截取Gyrator变换进行图像加密。原始图像和随机相位函数叠加后做Gyrator变换,矢量分解将Gyrator变换域信息分解为一个随机相位函数和一个复函数。随机相位函数和复函数分别做不同变换角度的Gyrator变换后截取相位得到一个公钥和加密图像,截取振幅得到两个非对称相位密钥。进行了理论分析和数值验证,同时,设计了解密光学装置。结果表示:两个非对称相位密钥做为私钥,三个Gyrator变换角度做为额外密钥,这对增强系统的安全性是有帮助的。

Image encryption based on vector decomposition and phase-truncated gyrator transform

To improve the security of optical image encryption system, a novel optical encryption is proposed based on vector decomposition and phase-truncated gyrator transform. The original image multiplied with the ran-dom phase function is gyrator transformed and the information in the gyrator domain is decomposed into a random phase function and a complex function. The random phase function and the complex function are performed by the phase-truncated gyrator transform with different transform angles. Then, the two gyrator spectra are, respectively, amplitude truncated to generate two asymmetric phase keys and phase truncated to obtain a public key and the en-crypted image. Theory is analyzed and numerical simulations are presented and the optical decryption scheme is de-signed. It is indicated that two phase keys are used as private keys and the three gyrator transform angels are also served as keys, which is helpful to enhancing the security of the proposed encryption system.