Research On Vector Quantization-Based Watermarking Algorithm

The rapid development of computer science and the popularity of network have brought both opportunities and challenges to the multimedia industry. A great number of multimedia products can be accessible from the Internet and CD-ROM, and the creation, duplication and distribution processes are extremely fast and convenient. Unlike analog media, digital multimedia products can be easily copied without decreasing their fidelities. As a result, the multimedia products may be illegally copied or maliciously tampered in the distribution process, which can infringe the copyrights and decrease the reliabilities of the original products. Thus, the issues of multimedia copyright protection and content authentication have attracted great attentions in recent years. The digital watermarking technique is proposed to offer a new solution to the copyright protection and content authentication problems. The digital watermarking technology can accomplish copyright protection and content authentication by embedding secret information in the original product.The multimedia data contain a great deal of redundant information, and thus must be compressed before transmission and storage. Vector quantization (VQ) is a popular lossy compression scheme widely used in multimedia data compressions. In order to implement copyright protection and content authentication of the VQ compressed data, the research work of this thesis focuses on the VQ based watermarking algorithm. The main research work and contributions of this thesis are as follows:The thesis first makes a systematical review of the related key techniques, including the basic concepts and principles of the digital watermarking and vector quantization techniques. Moreover, this thesis also summarizes the research statuses of the compressed domain watermarking and VQ based watermarking algorithms. Some of the typical algorithms are detailedly introduced and deeply analyzed in this thesis. These algorithms are the foundations of the research work in this thesis, and they also provide the basic thoughts for the research work.Based on the characteristic of motion vector, this thesis proposes a motion...