Image Encryption Algorithm Based On Chaos System

With the wide application of modern network information technology,the issue of information security has caused wide public concern.The same as texts,audios and videos,image data information has been becoming one of the mainly medium to obtain information in daily life.Thus,exploring the new encryption technology to achieve the security transmission of the image becomes a hot topic in the field of image encryption.Chaos attracts more and more researchers' attention and has been used in information confidential communications because of its great chaotic characteristics.In the field of chaotic cryptography,image encryption algorithm based on chaotic system is one of the most important algorithm.The performance of chaotic is proposed,which can improve the chaos characteristic of the whole chaotic system and design the image encryption algorithm with better encryption performance.For the study about the security of cryptography encryption,it is found that Logistic chaotic mapping has good chaotic characteristics,but the mapping itself still has low defects and simple structure.Based on this,we find that the piecewise Logistic map(PLM)and improved infinite chaotic map with iterative collapses(ICMIC),and then applies it to design image encryption algorithm.To this end,in this thesis the main research work includes the following research work:(1)The problems of the current classical chaotic mapping are analyzed,and the application of these chaotic maps is hidden in the security because of the simplicity of the phase space structure.Aiming at the above problem,an improved ICMIC chaotic map is proposed by combining ICMIC chaotic map.(2)According to the improved ICMIC chaotic map,this thesis proposes the image encryption algorithm based on the improved ICMIC chaos map,and then analyzes the encryption effect of it.(3)In order to overcome the disadvantage of Logistic map in security,this thesis proposes a spatiotemporal chaotic system based on PLM.That is to say,it makes the PLM as the local map of the CML to emerge the model of space-time chaos system based on PLM.Based on this,this paper proposes the color image encryption program based on chaos system.Performance analysis and simulation test results show that the proposed algorithm not only has high security but also can satisfy the requirement of transmitting image safely over the network.