New encryption method of 2D image by use of the fractional Fourier transform

Recently, secure transmission of image information has been very significant especially with the development in the Internet. In general, encryption of image has widely been known as one of the effective methods to realize the secure transmission. In this study, we propose a new encryption method of 2D image by use of the fractional Fourier transform (FRT) which is the generalization of the conventional Fourier transform (FT). Specifically the FRT with different order of the FT is conducted to the grayscale distribution in each line of the original image. The validity of our proposed encryption method is shown by analyzing the cross-correlation properties between the original image and the encrypted image.