The Research Of Digital Image Encryption Technology Based On Chaos System

With the development of science and technology,people pay more and more attention to the security of personal user information.As one of the important carriers of information,images bear the daily information interaction of people.Although there are a large number of encryption technologies,in view of the characteristics of digital images.traditional encryption technologies are no longer suitable for image encryption.Initial value sensitivity,ergodicity,and pseudo-randomness of the chaotic system are closely corresponding to the keys,diffusion,and scrambling in cryptography.Therefore,applying chaos theory to digital image encryption has been one of the most concerned and most promising image encryption technologies.This paper studies the digital image encryption technology based on chaotic system.The details are as follows:(1)The research status of chaotic image encryption technology is expounded.The basics of cryptography and chaos theory are introduced.The basic principles and methods of digital image encryption are introduced.The principles and steps to be followed in designing chaotic image encryption algorithms are summarized.(2)For the current image encryption algorithms based on chaotic systems and DNA encoding operations,DNA encoding and calculation methods are single,and the structure of chaotic systems is simple,a combination of multiple chaotic systems and DNA encoding operation image encryption algorithm is proposed.The algorithm makes a random matrix through Skew Tent map,then performs 8 x 8 block processing on the random matrix and the image R,G,B component matrix,then performs DNA encoding,then performs DNA operations on the two matrix blocks,and then performs DNA decoding operation,and finally merge block and image components to complete image encryption.The above encoding,decoding and DNA calculation methods are randomly determined by the Chen hyper-chaotic system.Simulation experiments demonstrate that the algorithm has high security and robustness.(3)Based on compressive sensing and double chaotic system,an image compression encryption algorithm that can realize both compression and encryption operations is proposed.Logistic map and Skew Tent map are used to construct a double chaotic system to improve the randomness of the chaotic sequence.The generated chaotic sequence is used to construct a measurement matrix and random matrix.Then each block is compressed and encrypted through the compressed sensing measurement projection,in order to increase the confusion of ciphertext images,random pixel projection,in order to increase the confusion of ciphertext images,random pixel exchange algorithm is used to further exchange and scramble pixels between adjacent image blocks.Simulation experiments demonstrate that the algorithm has high security and good compression performance.