The Watermarking Technology Research Of Raster Digital Maps Resisting Cropping Attacks

With the rapid development of computer technologies and network technologies, it, On the one hand, promotes the spread of digital words. On the other hand, it brings the copyright protection to troubles. As a special kind of digital works, Digital maps products are suffering from troubles by pirate. Digital watermarking technologies draw exports' attention because it is the most effective method for the protection of intellectual property rights.Having described and summarized the basic theory of digital watermarking technology, the thesis mainly studies the robustness watermarking technique of raster digital maps for intellectual property rights. After analyzing the research backgrounds and current development of the raster digital maps, the thesis emphatically researches and analyzes the communication model of the digital maps watermarking technique. As to those defects, a new watermarking model, which makes use of the side information, was introduced in the protection of digital maps. Then the thesis proposes a raster digital maps watermarking scheme based on Quantization Index Modulation technique, which can improve the defeats of resent watermarking algorithms for digital maps, and enhance the robustness and the imperceptibility of the digital watermarking system. Recently, there is no any watermarking scheme to resist cropping attacks in digital maps research. As to this research state, using the idea of embedding watermarking information in non-overlapped location of the spatial of the image for reference and introducing the technology methods in image search field, the thesis proposes a new digital maps watermarking scheme based on invariant moment methods extracting and matching with coordinate analysis to resist cropping attacks. The experiment results show that the digital watermarking scheme has a good performance on resisting cropping attacks. Last, the watermarking schemes achieve the expected effect.