Research On Image Blind Watermarking Algorithm Based On Hyperchaos

Network technology has changed modern people' lifestyle, people deliver information on the internet conventional. This convenience also brings possibility of digital copyright infringement when it provides people with convenient. The development of network will encounter bottlenecks without a safe enviorment. For this reason, it is necessary to creat an effective maintenance technology of the digital rights, and the digital watermarking technology has attracted people' attention. At present, this technology has played a large role in copyright protection.Digital image watermarking involves three important research directions. Firstly, how to improve the capacity of digital watermarking. Secondly, how to improve the security of watermark. Thirdly, how to improve the robustness of digital watermarking. This algorithm improve security with the method of initial value sensitivity of hyperchaos system, parameter uncertainty and pseudo random. Improving the capacity of the digital watermarking vith QR Code coding. Ensuring the robustness of the algorithm with frequency domain transform. Specifif research work are as follows:Firstly, thesis elaborate the research background, significance of digital watermarking technology and the development situation at home and abroad. Introducing the basic framework of the digital watermarking and performance evaluation, describing the digital image watermarking technology and the chaos theory detailedly. Providing basic theory basis for watermarking algorithm proposed later.Secondly, thesis provide a digital image encryption algorithm based on hyperchaos sequence, combining scrambling encryption and diffusion encryption. The security of watermark has improved after full use the characteristics of thehyperchaos.Thirdly, in order to increase the watermarking capacity, thesis provides a digital image watermarking algorithm based on QR Code coding. This algorithm can break the meaning of digital image watermarks out of simple binary image, and add mor complex information to the digital images.Fourthly, in order to improve the robustness of algorithm, thesis also propose an algorithm which based on Schur decomposition and wavelet transform, the algorithmusing the knowledge of matrix transformation theory and frequency transformation theory, adding the watermarking information to frequency domain which is the most difficult to be removed, through this method, the antiattacking is ensured.Last but no least, those above are all digital image blind watermarking algorithm, on the other word, the digital watermark can be extracted without original image. This algorithm has more practical significance.