Color image hierarchical encryption based on fractional Fourier transform and wavelet decomposition
Xingbin Liu · Journal of Nanchang University · 2012
A color image hierarchical encryption scheme based on fractional Fourier transform and wavelet decomposition is presented.The color image hierarchical encryption is realized by encrypting image data matrix and color index table respectively.The color index table is scrambled by using Logistic algorithm at first to obtain the first-level encrypted image.Afterwards,the image data matrix is dealt with single level wavelet decomposition and then the low-frequency component is encoded by double random phase encoding in fractional Fourier transform domain to obtain the second-level encrypted image.The final encrypted image is obtained by combining the scrambled color index table and the encrypted image data matrix.The scheme features high security and efficiency and simulation results verify the security and the validity of the proposed encryption algorithm.