Research On Encryption Algorithm Based On Image Bit Plane

Image encryption refers to the effective encryption and hiding of the original image information,and the ability to restore the original image information from the encrypted image with almost no loss.In a digital gray image,its gray level can be decomposed into a set of binary numbers,so the image information can be decomposed by bit-plane decomposition technology.The bit-plane-based decomposition technology is currently widely used in the field of image processing,such as image enhancement,image compression,and image encryption.This dissertation uses the bitplane information of the digital image to realize the encryption of different levels of the image.The main contributions of this dissertation are summarized as follows:1.An image encryption algorithm based on bit-plane traversal and nonlinear Sbox.In the proposed encryption algorithm,a bit-plane decomposition algorithm is used to decompose the original image into a bit-plane image,and the bit-plane image is subjected to a bit-bit vector traversal scrambling operation,and then the scrambled bitplane image is converted into an S-box replacement process using bit-plane synthesis The coefficient matrix in.Then use the S-box constructed by the chaotic system and the nonlinear equation system to perform the replacement operation on the coefficient matrix,and finally use the diffusion matrix generated by the chaotic system to perform the bidirectional diffusion of the replacement matrix to realize the encryption of the image.The algorithm is associated with plaintext in the process of scrambling and replacement,which further improves the performance of the algorithm against differential attacks.2.Image encryption algorithm based on compressed sensing and multiple bit positions.In order to reduce the data volume of the original image in the process of bit position disorder,the sparse representation of the original image is compressed and sampled by the random measurement matrix generated by the chaotic system and nonlinear function to obtain the measured value image of the original image,and then the bit position of the measured value image is obtained.Plane matrix,and then use different cutting and recombination methods for bit plane matrix,and use bit position scrambling algorithm to do bit scrambling operation,which can better reduce the correlation between pixels in the image and within the image.Experimental simulation shows that the algorithm has a good encryption effect and can resist a variety of attacks.