Research And Application Of Fragile Digital Watermarking Algorithm On Copyright Protection

With the rapid development of computer, network and communication technology, the problems of the security protection of information become more and more pressing. Based on the technology of computer and network, the sharing of multimedia information provides a convenient way for using and spreading digital products. Therefore, the characteristics that the digital products are easily copied and tampered make security protection problems of digital products up to urgent level. The digital watermarking technology as a new one of information hiding technology, it utilizes the redundant date and random in the digital products, and embeds imperceptible but distinguishable secret message-watermarks into the media in order to protect the intelligent property or the integrity of the working. Nowadays, digital watermarking technology has received extensive concern, and has became the international research focus in the academic circle.The thesis pays more attention and research on one kind of digital watermarking technology—fragile digital watermarking, which will be mainly used to integrity authentication of digital images. It utilizes the solutions combined by digital signature algorithm and fragile digital watermarking, and it will play an effective role in the promotion and application of the digital watermarking technique. Firstly, we have done some analyze and experiments on existing solutions, and evaluated their strong points and weakness. Secondly, we provide an improved solution and its prototype to make it more suitable for the actual project. Finally, we have concisely introduced a kind of short digital signature algorithm—QUARTZ and CFS, and we predict the short signature algorithm will become the principal technology to combine with fragile digital watermarking algorithm.