Digital Watermarking And Algorithm Research

This paper simply introduces the emergence and development of digital watermarking, related software products and status quo of researches both at home and abroad. Three prevalent watermark architectures are respectively discussed about their radical structures, generic problems, key techniques and classical algorithms. The author does some necessary analysis, compares advantages and disadvantages of classical algorithms and presents respective fields of application. With the fact that different watermarking architectures apply to different fields, we propose characteristics and general attack of robust watermark to copyright protection and fragile watermark to integrality. Furthermore, solutions are suggested.With still image and readable watermark being research subjects, the paper presents a wavelet-energy based tactic by wavelet. Simulations prove that algorithms which are based on wavelet-energy can embed not only robust watermark, fragile watermark, but also some multiple multitype watermarks. In processing of multiwatermark, every watermark is adjustable and independent of each other. When extracting watermark, we don't need original watermarks, but original image.