Research On Robust Algorithms Of Digital Image Watermarking

As the sharply developing of the Internet technology, thecommunication of information especially the communication of digitalinformation reaches a height which we can never reach. It not only bringsconvenient communication, but also takes a baptism to the copyright ofthe digital products: who owns the copyright, and whether the productshave been tampered with or not. This problem has attracted widelyattention to the pursuers: How can we not only take full advantage of theconvenience of intemet, also protect the copyright and the content of thedigital products? The Digital Watermarking technology can resolve thisproblem very well. It can advance the development of the copyrightprotection technology world widely and has good potential applicationvalues, so it has been studied widely.In this dissertation, robust digital watermarking algorithms, basingon transform domain of the digital image, are studied. They are detailedas follow:(1) The author analyzes the background of the digital watermarkingin details; explains the theory, the practical meaning of the digitalwatermarking, the conception, and the characteristics etc.(2) The author introduces the essential theory of the digitalwatermarking technology, including the general model of thewatermarking, how to design the watermarking signal. At the same time,the author analyzes some normal digital watermarking algorithms andanalyzes the importance of the robust of the watermarking.(3) The author studies the application of the Ergodic Matrix in therobust watermarking algorithm. At first, the author introduces themathematics theory of the Ergodic Matrix, and analyzes its applicationduring the pretreatment of the image scrambling. Then a novel robustimage watermarking algorithm, based on Ergodic matrix and DWT, isproposed. At last the writer analyzes and demonstrates the robustness ofthe algorithm thoroughly with the experimental result.(4) This paper also researches the Singular Value Decomposition(SVD) of the matrix and its application in digital watermarking. The author introduces the matrix's SVD firstly, and then he proposes a digitalwatermarking algorithm which bases on the improved SVD. At last, thewriter analyzes the robust of the watermarking system which bases on thealgorithm by the experimental result.Finally, the author summarizes the work has been done in the paperas well as highlights some further research directions.