Research And Design Of Hidden Attractor Chaotic Image Encryption System Based On Random Shuffle Algorithm

At the beginning of the 21 st century,with the rapid progress of network technology,a large amount of information is trans mitted through the network,but due to the openness of the network,information security issues have become particularly important.How to ensure the security of the information transmitted on the network has become a hot issue,encrypting the information to be transmitted is the most common processing method in the field of information security today.Digital media is usually used as a carrier for transmitting information in the network because of its vivid and intuitive characteristics.Am ong them,it is particularly extensive to select digital images from digital media as carriers for transmitting information.However,because of the high degree of correlation between adjacent pixels of digital images,high redundancy,large data volume,two-dimensional distribution,etc.,traditional encryption schemes are often not suitable for encrypting digital images.In recent years,the theory of chaos has developed rapidly.Researchers have discovered that chaos is unpredictable,sensitive to initia l values and system parameters,pseudo-random,and ergodic.These characteristics make chaos very suitable for encrypted images.In the foll owing research,it was found that the application of chaos theory to image encryption not only has good security performance,but also improves the encryption speed,which solves the defects of traditional encryption schemes to encrypt digital images,and attracts a large number of scholars to study chaotic images encryption.The main research of this thesis is to encrypt the image by hidden attractor chaotic system.First,the background and significance of the research work are pointed out,and the domestic and foreign research status of chaos,hidden attractor chaos and chaotic image encryption are summarized;th en,the chaotic system,hidden attractor chaotic system,cryptography,chaotic image encryption and random shuffle algorithms are briefly introduced.Finally,two image encryption schemes are designed based on the hidden attractor ch aotic system.The brief introduction is as follows:(1)An image encryption scheme based on hidden attractor chaotic system and Fisher-Yates random shuffle algorithm is proposed.In this scheme,the hidden attractor chaotic system is used to generate the c haotic sequence required for chaotic image encryption,which overcomes the security defect of image encryption based on the self-excited attractor chaotic system.Fis her-Yates random shuffle algorithm is used to scramble the image,which can make the scram bled image have better randomness.The bidirectional cyclic XOR operation is applied to the diffusion process in image encryption,which can cause the information of each pixel in the image to be diffused to all pixels in the image.(2)An image encryption algorithm based on hidden attractor chaotic system and Knuth–Durstenfeld random shuffle algorithm is proposed.The dynamic characteristics of the hidden attractor chaotic system in this encryption scheme are more complicated.Under certain system parameters and initial values,the system has hyperchaotic dynamic behavior.The Knuth–Durstenfeld random shuffle algorithm is used for scrambling,which makes the algorithm get a better random scrambling effect in the case of lower time complexity and space complexity.DNA sequence manipulation is applied to the diffusion process of image encryption.In this thesis,the proposed encryption schemes are simulated and analyzed on the MATLAB simulation software.From the experimental results,the proposed encryption scheme has higher security and can resist common attacks.