关键词: Arnold置乱, 图像加密, 全息图, 脆弱性

Abstract:

In order to increase the security performance，a novel encrypt algorithm is proposed.Traditional Arnold transform is investigated，and its period is analyzed and found to be related with the size of image.A novel pixel scrambling algorithm is advanced to unify the histogram and augment the key space.Several random numbers generator methods，namely twister method，shift-register generator，modified subtract with borrow generator，chaotic generator，are compared.The twister method is found to be best since the corresponding period and key space is the largest.The hologram is calculated to be the final encrypt image.Experiments show the validness and efficiency of the proposed algorithm，and the strong frangibility to cropping attack，noise attack，and JPEG attack.

Key words: Arnold scrambling, image encryption, hologram, frangibility