Research And Improvement Of Seal Domain Digital Watermarking Security System

Seal domain watermark security system combines PKI/CA platform with the seal domain watermark technology. The system expands the application fields of digital watermark and PKI technology from the digital domain to the analog domain to protect both digital documents and paper documents. Therefore, it has become a research hotspot for its practical utility. What's more, it would be widely used, if we could make the system completely portable.In this paper, we summarize the main weakness of the existing Seal domain watermark security system. We also find a perfect solution to solve the problem for the system. In the meantime, in order to popularize the Seal domain watermark security system, we raise a design scheme for Portable equipment, and implement the Portable Watermark Detector on FPGA. The valuable research fruits are as follows:1. After analyzing the existing Seal domain watermark security system, we find that it doesn't support various kinds of seals. According to the problems we have encountered, this paper presents the corresponding solution. Based on the knowledge of rectangular degree, circular degree and moment invariants, we design an algorithm of image classification for seal image. After a lot of experiments, the result proves that this algorithm can help us to solve the problem we have mentioned before.2. Based on our scheme, we implement the Portable Watermark Detector on FPGA. Meanwhile we used the C2H hardware accelerator in order to improve the performance of system. The result proves that the whole speed performance promotes a lot, and meets the real-time requirement.