| As the main means of protecting image information security,image encryption has become a key issue in the field of information security in recent years.Double random phase encoding(DRPE),as one of the most representative technologies in the field of optical information security,has been widely used in the field of image encryption in recent years.This paper summarizes and analyzes the general framework of DRPEbased optical image encryption,and proposes a new encryption technology under the general framework.The details are as follows:(1)After reading a lot of literature,this article gives a general framework based on DRPE optical image encryption technology.The main elements of a general framework include preprocessing operations,random phase masks,and optical transformations.This paper introduces the representative preprocessing operations of the Arnold transform,singular value decomposition and compressed sensing,generating onedimensional and two-dimensional chaotic maps of chaotic random phase masks,and commonly used optical transformations.(2)Based on the general framework,the random phase mask is improved,and a method for generating a chaotic palmprint phase mask biokey from palmprint,chaotic random phase mask and amplitude truncated Fourier transform is proposed.The chaotic palmprint phase mask can replace the random phase mask.The uniqueness of the palmprint can improve the security of the encryption system.An optical image encryption technology based on biological key and singular value decomposition is proposed.During the encryption process,the image is subjected to singular value decomposition after optical encryption.Three parts are obtained by multiplying the two to generate a private key,and the other part is used for subsequent encryption.Effectively resists selected plaintext attacks.Numerical simulation results show the feasibility and security of the proposed encryption system.(3)Based on the general framework,vector decomposition is introduced in the preprocessing stage,and an optical color image encryption system based on vector decomposition and chaotic palmprint phase mask is proposed.In this method,the image is first encrypted by a vector decomposition operation.The two phase plates obtained by the vector decomposition are used for subsequent encryption and one is used as a private key for decryption.The introduction of vector decomposition makes the encryption system asymmetric and resistant to selective plaintext attacks.A large number of numerical simulation experiments verify the feasibility and security of the encryption method.(4)Introduce non-negative matrix factorization in the preprocessing stage,and propose an optical grayscale image encryption system based on non-negative matrix factorization and Gyrator transform.In this method,the image to be encrypted is first subjected to a non-negative matrix factorization operation to obtain a base matrix and a coefficient matrix.The coefficient matrix is subsequently encrypted,and the base matrix is used as a key.The advantage of this method is that the image is compressed after non-negative matrix factorization,which can save storage space and computing resources.Numerical simulation results show the feasibility and security of the proposed encryption system. |
