The Research On Chaos Application On Image Encryption

In this information age, with the technology of the communication and internet, more and more messages are transmitted in the internet. The security of messages became more and more important that make the encryption theory and technology to be a primary domain of the information science and technology. Many governments have attached great importance to the reveal of messages, because it threatens the national defense and economy. Chaos widely exists in our natural world as a series of stochastic process in non-linear deterministic dynamical system. Because chaos is extremely sensitive to initial conditions of the chaotic system, and a large number of non-periodic, continuous broadband frequency spectrum, noise-like, yet deterministic and reproducible signals can be generated, it has natural concealment. What's more, chaotic signals can't be forecast for a long term, and it is extremely complicated, and easily realized, the application of chaos theory has been one of important issues and forefront project.This work mainly includes the design and realization of the chaotic cryptography, especially the cryptography algorithms of images that used chaotic sequences. The author scientifically introduced the development of the chaotic security communication and the principle of modern cryptography. This work pays emphasis on the application of chaotic sequences in cryptography and the theoretical analysis of their performances and proposed a novel chaos map. On this basis, the author chose two types chaotic map, and blends them together to propose an image encryption algorithm. At first, the work described the algorithm in detail, and then simulated the algorithm in the computer in order to analyze the performances (such as key spaces, sensitivity of the key and the statistical performances) of the algorithm. The results of the simulation showed that the algorithm based on mixed chaotic dynamic systems is greatly sensitive to the key and the algorithm has a large space of the key, a good encryption speed. Moreover, a better security performance of the statistical analysis is acquired.The paper finally has carried on the summary to the researchwork, and has made the forecast to the future research direction.