Image Encryption Algorithm Based On Latin Square Matrix And DNA Sequence Operation

The Internet of Things,cloud computing,big data,etc.,have penetrated into all areas of urban life,and also brought a whole host of new opportunities and challenges to upgrade China's economy which acts as the “engine” nowadays.Information security is the foundation of these new technologies.The digital images are transmitted and stored via various networks and devices due to the advantages of images,such as intuitive,vivid,informative,etc.It takes conveniences to our life.However,the security issue of image information has been exposed increasingly.The chaotic system has excellent characteristics,such as,extreme sensitivity to initial values and parameters,nature of mixing,rapidly attenuate autocorrelation,long-term unpredictability,pseudo-randomness,etc.So it is suitable for chaotic system to achieve digital image encryption.What is more,the DNA-based computation is utilized in the fields of information security,mathematics,medicine and electronics,etc.Because of that the DNA-based computation has high parallelism,massive storage capacity and lower energy consumption.The paper elaborates the basic knowledge of digital image encryption and the relevant theories of chaotic system and DNA computing firstly.And then,the chaotic system,Latin square matrix and NDA coding are proposed to design the digital image encryption algorithm,results from digital simulation and the analysis of algorithm performance are obtained.The main steps are as follows:1.Based on relevant methods of DNA coding,chaotic system and orthogonal Latin square circulant matrix,an image encryption algorithm based on orthogonal Latin square matrix and DNA sequence operation is designed.In this algorithm,the images are divided into three components by the RGB color mode.A random sequence is generated from the LSS-CML chaotic system.Firstly,encoding the three components mentioned above by DNA coding.And then scramble the encoded matrix by orthogonal Latin square circulant matrix;Secondly,running calculations with the coding rules.And then scramble the matrix by the sequence that generated from chaotic system;At last,after DNA decoding,the final ciphertext image is obtained by performing XOR operations and other algorithm.The innovations of this algorithm are as follows:(1)The algorithm adopts the LSS-CML chaotic system,compared with the one-way coupled map lattice(OCML)chaotic system,it has better randomness;(2)The algorithm uses orthogonal Latin square matrix and DNA coding to scramble and diffuse the matrix,weakening the strong correlation between the pixels of the matrix,and enhancing the sensitivity of the ciphertext.2.Since a Latin square matrix can be constructed by a circulant matrix,an improved color image encryption algorithm based on orthogonal Latin square circulant matrix is designed.During the key generation phase,two hexadecimal sequences are referred.One of which generates an orthogonal Latin square circulant matrix,the other acts as initial values and parameters.During the encryption,chaotic systems are processed to scramble any two components in a pair to generate three matrixes by bitwise XORs;and then the matrixes are merged into four blocks for row and column transformations;the value of the Latin square circulant matrix is set as coordinate index when it has been scrambled,they will performed XOR with chaotic system sequence;finally,the XOR algorithm is performed again to spread the Latin square matrix and chaotic key stream.The innovations of the algorithm are as follows:(1)Using Hash function to generate keys,which enhances the randomness of the key sequences;(2)The three components are combined into a matrix,and row and column placement is scrambled on the matrix after the blocking;(3)The Latin square(circulant)matrix is used to perform two diffusion operations on the scrambled image mentioned above,which increases the degree of diffusion of the ciphertext.After analyses of information entropy,histogram,correlation,lossless and other aspects from experiments,the algorithm has the advantage of being able to resist attacks from unknown operations.Finally,research summary and some expectations for the future development trend of image encryption is made.