Blind Watermarking Method Based On Wavelet Tree And Human Visual System

The fast development of Internet makes it convenient to access the multimedia data. But at the same time the Internet has brought a new challenge to the copyright protection. As an effective means for the protection of digital property rights, the technique of digital watermarking is an important part of the region of information hiding and attracts wide attention. Digital watermarking is a technique that embeds copyright information, such as figures, sequence numbers, words, image logos and so on, imperceptibly into multimedia data. It can be used for tracing the distribution and usage of multimedia data. The special application of digital watermarking technique requires that the embedded watermark should be not only transparent to human observers, but also robust enough so that it cannot be easily destroyed or removed after some digital image processing or attacks.The basic concept and theory of digital watermarking is first described in this paper. According to the different ways of information hiding, the existing algorithms of digital image watermarking are concluded and compared. Based on the shortcoming of the existing algorithms, we propose a blind watermarking method based on wavelet tree and human visual system (HVS). In the embedding scheme, the wavelet trees are extracted from the host image. Then the watermark is embedded into the wavelet trees based on human visual system. By the proposed method based on HVS, the image problem of changing much can be solved, so as to keep robust.We simulate the algorithm in the computer and test the performance of watermark embedding, watermark extraction and the detection, extraction and recovery of the embedded watermark after different kinds of attacks. Experimental results show that the algorithm is feasible and robust.