基于分数阶Fourier变换的数字图像加密算法研究

Research on digital image encryption algorithm based on fractional Fourier transform

基于分数阶Fourier变换和混沌,提出了一种数字图像加密方法。具体算法为:先对图像进行混沌置乱,再进行X方向的离散分数阶Fourier变换;然后在分数阶Fourier域内作混沌置乱,再进行Y方向的离散分数阶Fourier变换;最后将加密图像的实部与虚部映射到RGB,形成可传输的彩色加密图像。实验结果表明,该加密算法具有很好的安全性,在信息安全领域有较好的应用前景和研究价值。

This paper proposed a new approach of digital image encryption based on the fractional Fourier transform and chaos.The algorithm could be summarized as follows.Firstly,scrambled the image in time domain with chaos,and then combined it and the discrete fractional Fourier transform in X direction.Secondly,scrambled the image obtained in the fractional Fourier domain with chaos,and then combined it and the discrete fractional Fourier transform in Y direction.Finally,mapped the real and image part of the encrypted image to the RGB,forming a color image for transmission.The experiment results show that the algorithm performs considerable security,which has well research value and application foreground in the information security field.