Implementation Of Chaotic Image Encryption System Based On DSP

With the development of network and improvement of information-processing technology, large numbers of images are transmited through network. It is very important to guarantee the security of these informations. Image encryption is one of the most important means to keep secure. In the existing algorithms, chaotic system shows powerful superiority on image encryption. Compared with traditional software encryption, hardware encryption has advantages of fast, independent of PC and preferable security. This paper discusses the method of implementation of chaotic image encryption system based on DSP. And then, the paper specifies the design of algorithm, hardware and software of this system.Firstly, this paper presents theory of chaotic system, principle and method of chaotic encryption, and then analyses chaotic encryption techniques and some applications in the field of image encryption. After choosing Logistic map as the starting point of research, this paper analyses its encryption characteristic and points out its secure problem. The application of hyperchaos is one of research emphases of present encryption technology. Based on analysis of hyperhenon map, this paper proposes a new mixed encryption algorithm improved to attain good security. Emulational results indicate that this algorithm has outstanding advantages such as great secret key room, highly complexity signal and good random property, which is suitable for applying on the platform of hardware.Design of hardware is the focus section of this paper. Firstly, it discusses DSP technology and some applications. And then based on the structure and character of TMS320VC5416, this paper analyses the image encryption system in detail and gives the working principle of system. Structure of the hardware consists of four parts: DSP hardware circuit, interface circuit of USB, interface circuit of Flash and power circuit. This paper presents their ideas of design, structures of circuit and working principles.This paper also discusses the software design of chaotic encryption system in detail. Software design in this system is consist of DSP program, USB firmware, USB device drivers program and application program. This paper introduces the process of development, function of realization, flow chart of program of DSP program and USB firmware in details, and USB drivers and the programming methods of application in brief.