Research On Digital Watermarking Technique Of Wavelet Domain

Today’s society is moving into a high-speed information age.The rapid development ofscience and technology, the fast progress of society, and especially the popularity of theInternet have accelerated the speed of information process. The popularity of the Internet topeople’s lives has brought great convenience, but also provides convenience for somelawbreakers to commit. In recent years, the network violations occur frequently, and researchscholars of the information security aspects introduce digital watermarking technology.This paper first disscusses the background and significance of the digital watermarkingtechnology, development Status at home and abroad and applications, then digital watermarkingthe basis of theoretical knowledge to do a specific description, including digital watermarkingtechnology systems theoretical framework, the classification of digital watermarkingtechnology, features attack testing methods, performance evaluation criteria, as well asclassical digital watermarking algorithms.Secondly, the concept of wavelet transform, continuous wavelet transform(CWT)anddiscrete wavelet transform(DWT), two-dimensional image of the wavelet transform andwavelet transform applied to digital watermarking technology is briefly introduced in thepaper.Then paper briefs the singular value decomposition (SVD)and its characteristics.analysisand improves the method based on SVD watermark embedding,and it is used in the DWTdomain and discrete wavelet transform-discrete cosine transform(DWT-DCT)hybrid domaindigital watermarking algorithm. After tested by simulation experiments, the results shows thatthe improved embedding method can not only ensure the security of the watermar,Then the human visual system, the characteristics and the just noticeable difference (JND)threshold model based on human visual system is described in the next part of thepaper.Combination of theoretical analysis and experimental testing. Amends the JNDthreshold model proposed by Lewis as appropriate with theoretical analysis,experimentaltesting and discussing. And the modified threshold model application is used on the digitalwatermarking algorithm based on the wavele domain of the human visual system. The resultsshows that the the JND gate limit the improvement of the model is correct and feasible aftertesting with simulation experiments.A method based on wavelet domain image of the human visual system sub-blocks of thewatermark embedded is presented at last,and it is applied to the dual watermarking algorithm based on wavelet domain of the human visual system. Embeddes the confirmed watermark inthe high-frequency sub-band by using method on SVD for image authentication watermark,meanwhile embeddes authentication watermark by using the watermark embedding that paperpresents,the JND threshold and sub-block property embedded in the same sub-bandtransform scale. After testing with simulation experiments, The results shows that thewatermarking algorithm not only good counterbalances of invisibility and robustness,but alsotakes into account the safety and image quality impact of the watermark.