The Research On Image Encryption Algorithm Based On Chaotic MAP And DNA Coding

With the rapid development of Internet technology,a large number of image information are used and spread in daily life,such as military operations,e-commerce,scene monitoring,and telemedicine.Image have many own characteristics,such as the data is two dimensional,high redundancy of pixels and big data,etc..Therefore,it has become a crucial issue that how to ensure the security of image information and encryption efficiency.Chaotic map s have the characteristics of ergodicity,pseudo-randomness,high sensitivity to initial conditions and the cost of is low.It is widely used in the field of image encryption.Due to the large amount of data in the image,how to keep the security and the efficiency of encryption algorithm becomes a critical research issue.Therefore,we will study the image encryption algorithm based on chaotic maps.In this thesis,we first study the image encryption algorithm based on chaotic maps.Recently,Wang et al.proposed an image encryption algorithm based on Chebyshev map called IEACM.Their algorithm combines scrambling encryption and diffusion encryption.However,we find that the algorithm can not resist the chosen plaintext attacks and point out the security weaknesses.We demonstrate the effectiveness of our attack method throughout theoretical analysis and simulation experiment.Then,we proposed an improvement based on their algorithm called IEACMI.The experimental results show that our improvement can resist the proposed chosen plaintext attack.Meanwhile,the efficiency of our improvement is better than Wang et al.'s algorithm.With the development of DNA technologies,many researchers apply the DNA sequences to the image encryption.Therefore,combining the chaotic maps with the DNA coding into image encryption is received much attentions.It provides a higher security level than chaotic map based or DNA coding based image encryption algorithm.Thus,we then study the image encryption algorithm based on hyper-chaotic map and DNA coding and propose a concrete algorithm called IEHDC.In our algorithm,the encryption procedures are consisted of scrambling the positions of the pixel values,encoding the pixel value with DNA sequences,and diffusing the DNA sequences with the pseudo-random sequences generated by a hyper-chaotic map.Finally,decoding the results of the encrypted DNA sequences to be a cipher image.In the experimental comparisons,we compare our IEHDC algorithm with IEACMI and recent proposed algorithms in terms of key space,key sensitivity,correlation analysis,and differential attacks.It sufficiently demonstrate that our IEHDC algorithm has a higher security level and is secure against known attacks as well as providing efficiency and security.