Research On Chaos Arithmetic For Image Safety Transmission

According to the rapid development of computer technique and the prompt increasing of communication technique,making computer network technique more and more perfect and taking incorporate process of whole world in advance.Many people pay attention on the safety of image information which is still taking important role in safety of network information.But,because of traditional image encryption method are not suitable to characteristic of image information, so more and more special image encryption methods has been proposed,Chaos image encryption is the best encryption method by its many outstanding characteristic.Even one-dimensional chaotic sequences has small secret key space and low security,but we can use its excellence characteristic,such as stochastic chaotic sequence,sensitive to initial conditions, fast cryptic key generating,highly sensitive to cryptic key. In this paper,we suggest two type chaos image encryption method base on the good point of chaotic sequence.This paper briefly introduces the current status of image encryption method,and introduces definition and concept of chaos theory together with Cryptography.Then mainly introduces two chaos image encryption schemes for image safety transmission.For the first encryption schemes,we suggest one compound chaos image encryption method with time-varying multilevel initial parameters to get the capability of "one time one secret".This algorithm combines Subsection-linearity mapping,Chebyshev mapping with Logistic mapping in order to disturbing values of each image point and the array of original images based on chaotic second-scrambling way. In order to solve the finite precision effects issue of digital chaotic sequence,we suggest the second encryption method which use one chaotic sequence disturbing parameters of another chaos mapping.The simulation results show that the algorithm has good encryption effects,large key space, fast encryption speed, and high security.