Research And Application Of Digital Watermarking Technology Based On Relational Database

With the development of information technology, protection of copyright for relational database has been more and more important. As an important branch of information hiding technology, watermarking based on relational database can embed copyright information into the original database, without destroying the usability of database. Therefore, studying on the watermarking based on relational database has great significance in terms of both theory and application.On the basis of researching and improving the current watermarking algorithms of relational database, a new algorithm for relational database based on Blakley secret sharing scheme is proposed in this paper. By secret sharing, the watermarking information is distributed more far-flung, and only part content of watermarking is needed when recovering the watermarking. This algorithm can improve the robustness.The paper presents a database watermarking method by using image. In this method, three-bit group idea is introduced, which can imbed 3 bit in every element's value.In order to broaden the application fields, a new watermarking method for protecting non-numerical databases is designed in this paper. The proposed watermarking system allows the data owner to define a similarity function in order to reduce the distortion caused by watermark embedding and, at the same time, reduce the number of element modifications needed by the embedding process.Finally, this paper develops software of watermarking system, applies the algorithm carried out in this paper into watermark system and realizes the embedding and recovering of watermark information in relational database.