Digital Watermarking Based On Wavelet Analyse

With the rapid development of multimedia and network technique, it becomes more and more convenient for people to gain digital products. But how can the authorships protect their copyright and economic benefits? Are these digital products safe and credible? In order to deal with these problems, a new technique entitled Digital Watermarking which could effectively protect the copyright and maintain the security of digital products was proposed internationally in recent several years.Digital Watermarking is a bran-new information security technique which can realize the functions of information hiding, memory and copyright protection by embedding the sightless information into digital media. At present, Digital Watermarking has become an effective and recognized method for multimedia copyright authentication and integrity protection.This dissertation did a comprehensive research about Digital Watermarking.Firstly, the basic theory and status both at home and abroad including character, classification, application, framework, attack and typical algorithms of Digital Watermarking was introduced.Secondly, the basic knowledge of wavelet transformation including the background of wavelet analyzing, consecutive wavelet transformation, discrete wavelet transformation, multi-differentiating analyzing and Mallat algorithm was briefly introduced.Thirdly, a Digital Watermarking Algorithm based on wavelet region was introduced. This dissertation also did the embedding, distilling and cutting of a watermark through this method.Fourthly, an algorithm about orientation of falsification of digital images was introduced. This part embedded the watermark signals which were created by the image itself into the wavelet region, also the Arnold transformation was imported to increase its robust. The results of simulation indicate that this algorithm has the functions of falsification testing and orientation. The detail process is : Firstly, do three-stage wavelet transformation to the image, distill and dispose the low spectrum component of the third stage as watermark information, At the same time, The embedded watermark is shuffled and we get the key. Finally, distill the signals of the third-stage low spectrum component from the falsified watermarked image through the way of creating watermark, and we extract the watermark. directly do subtraction with the signals distilled from the third stage low spectrum, then the falsification orientation is fulfilled.Lastly, summarized the whole work and showed the prospect of watermarking technique.