Research On Digital Watermarking Of Contourlet Domain

Digital watermarking technique is widely researched,which is a new method for information security and copyright protection. On the one hand, although many methods are proposed, most of them still can't resist geometrical attacks. So the researches on digital watermarking technology that are resistant against geometrical distortions are becoming more important. On the other hand, Contourlet transform is a new development of wavelet transform and its characteristic is better than wavelet. So the researches on digital watermarking technology based on Contourlet transform are becoming a new direction. This paper takes color images, original video, fingerprint images and gray images as examples respectively and five new digital watermarking methods based on Contourlet transform are introduced.Firstly, a color image blind watermarking method based on the formula of ten digits in the Contourlet transform domain is proposed. The original binary watermark image is encrypted through chaos scrambling technique, and then repeatedly embedded into the Contourlet transform low frequency sub-band of RGB color components. According to the formula of ten digits, the coefficients of low frequency sub-band are modified. The experimental results show that the algorithm is simple and effectly and it is very robustness.Secondly, a robust copyright protection scheme for digital videos is proposed which combines Krawtchouk moment with Contourlet transform. The features of the video sequence are extracted by Krawtchouk moment and Contourlet transform. Then the message is registered at the fair third party in order to gain the timestamp. Finally, we can use the timestamp to prove who the real owner is. The experimental results show that the scheme makes no difference of visual quality. Simultaneously it can well resist geometrical attacks and some other attacks, such as losing frames and median filter.Thirdly, a new scheme of network dual authentication is proposed. In light of the combination of the technologies of digital watermarking and fingerprint reginition, and taking advantage of the invisibility of digital watermarking and the uniqueness of fingerprint recoginition, this model blends two physical authentication factors: the user's information and the user's fingerprint features, in order to realize the dual authentication of users'identification. The experimental result shows that, this scheme greatly improves the reliability and security of network authentication.Next, an immune digital watermarking algorithm based on Contourlet transform is introduced. The experimental result shows that this immume watermarking algorithm is immune against ordinary watermarking attacks and it can recovery the carrier image from itself. And it can protect the copyright of digital works more directly and effectively.Finally, a multipurpose watermarking scheme based on wavelet moment and HVS is proposed. The experimental result shows that this algorithm is robustness and frangibility at the same time.