Abstract:

With the advent of digital era, digital watermarking exerts more and more influences in the area of copyright protection, broadcast monitoring and content authentication etc. After more than 10 years development, digital watermarking has achieved great accomplishments in the aspects of theory, algorithm, application and so forth. However, most existing watermarking researches focus on single watermarking; research on multiple watermarking is relatively less. Multiple watermarking has special application situation and value, thus the research on multiple watermarking and its application are of great significance. This paper firstly studies the advantages and disadvantages of the typical multiple watermarking methods such as re-watermarking, segmented watermarking, composite watermarking and spread-transformation watermarking, and then analyses the problems of copyright protection in the process of digital works transaction, designs and implements a digital works transaction system based on the selected segmented watermarking. In this system, the watermark containing the information such as author identity and create time is embedded into the author's works, and then the works are delivered to the publisher, while the publisher's information is embedded into the works. Before the works are sold out, the watermark containing specific consumer’s information is embedded into the works. The experiment result verifies the effectiveness and robustness of the designed system. At last, this paper prospects the foreground of the multiple watermarking.

Key words: multiple watermarking, digital works transaction, robustness, effectiveness