Image Encryption Based On Chaos And Its DSP Implementation

With the rapid development of Internet technology and the rapid updating of Internet thinking, digital media information has become an important way and means of communication, data and multimedia content has been widely applied to every field of people’s. At the same time, the people are also getting the confidentiality requirements of information transfer is higher and higher, the demand is not limited to the specific political and military applications, but deep into the daily life of the people. The encryption algorithm used while traditional to encrypt multimedia digital information, but the large quantities of data encryption speed and safety has been difficult to meet the requirements of the people, so as to encourage and promote the safety and speed of encryption algorithm. It is also through the research on chaos, the vision of people have been greatly expanded, and it also active people’s thinking. In some sense, chaos transform the traditional science, promote the further development of other disciplines.The most characteristic of chaotic maps are completely in line with the basic requirements of cryptography, it has a huge advantage in the field of secure communication. Also, it has increasingly become the focus of study in the field of secure communication.This paper based on the characteristics of chaos, which combined with some characteristics and requirements of the traditional cryptography. Then it designs several chaos based on image encryption algorithm, and using the MATLAB software platform for the simulation and the performance comparison of the DSP hardware. At last, it use TI TMS320DM6437to implement the simulation results. The main work of this paper is to:(1) Based on the study of traditional cryptography and chaotic block cipher, a4D dimensional extensive cat map and a novel fast image encryption algorithm based on the map are proposed in this paper. By the research and comparison of two-dimensional cat mapping, four-dimensional cat mapping, two-dimensional Henon map and the Logistic mapping, this paper designed four kinds of image encryption algorithm based on chaotic map, pointed out the advantages and disadvantages of algorithms in the theoretical. (2) These4image encryption algorithms were simulated by MATLAB in this paper,It made the conclusions by combining with theoretical analysis of the simulation resuhs.In addition, after these four kinds of algorithm simulation, from the correlation between the pixels, the smoothness and uniformity of distribution histogram, the basic dynamic characteristics of chaotic map and encryption of the data this time four areas for a detailed comparison, the paper prove the reason for poor performance of image encryption on Logistic map, but also to verify the advantages of four-dimensional cat map for image encryption.(3) These four kinds of chaotic encryption algorithms were validated On the TMS320DM6437DSP hardware platform,for the relevant tests to verify the foregoing analysis.From a hardware point of view and verify the accuracy of the simulation results.