Color Image Watermarking Based On Wavelet Transform

With the rapid development of multimedia technology and especially growing of Internet, we can get digital information conveniently and quickly. At the same time, the question of digital media copyright protection and authentication is becoming more and more important, thus digital multimedia copyright and security have become one of hotspot questions. Digital image watermarking is a kind of new technology for copyright protection, and is also one of effective methods to protect author's profit. In fact this technique utilizes image process methods to hide some information. The key of digital watermark to copyright protection is the imperceptibility and robustness for embedded information.In this dissertation, Firstly, some relative concepts, basic speciality, application range and developing status are introduced on watermarking technology, then, explains basic principle to fulfill it. Secondly, some algorithms which watermark signal are embedded are explained by citing some classical algorithms on spatial domain and frequency domain, and then these algorithm's characteristics are analyzed respectively. Finally, several color digital image watermark algorithms are introduced in detail, and a watermarking algorithm is proposed about color image. Experiment testifies that the algorithm has better robust to some common attacks.