A Method Of Embedding Watermark Into Color Component Based On Texture Division

Watermarking is a new information hiding technology. Its principle is embedding the copyright authorization information into the under-protection media like image, audio or video.Watermarking technology makes up for the digital signature, so that it has become the foreland of multimedia information hiding field and been well researched as well as been widely applied.The major research works and innovatory points in this thesis are as follows:Investigate the basic principles and characteristic of digital watermarking technique, introduce the research backgrounds, basic principles, application areas, and recent development and the future of the digital watermarking technology.Analyze the algorithm of Mallat and the concept, characteristic of wavelet transform which includes the continuous wavelet transform and the discrete wavelet transform, point out the advantages of using wavelet transform in digital watermarking and mufti-resolution analysis.A new meaningful digital watermarking algorithm for images is presented, which is based on texture segmentation and human visiual system .Taking the characteristics of the image itself, divide the image based on the texture. Then control the embedding strength according to the complication level of the different texture areas. Embed using higher strength coefficient in the high texture area. In this way, we meet both the robustness and the invisibility; second, taking the partial feature into account to choose the embedding color component. We don't choose the color for the whole image but for each image block which we get from previous division. We try our best to embed the watermark into green color component which has a better resistance to compression; Making use of masking peculiarity of human visual system, the watermark image is adaptively embeded into the blocked lowest approximation components of the image on DWT embedding technology, while most of other DWT (Digital wave translation) methods embed watermark into the middle or high frequency components. And before embedding, the watermark picture is processed, which is to enhance the robustness of the watermark. Experimental results show that the proposed algorithm keeps the quality of the image well and is robust enough to JPEG compression, noise, filtering, image scaling, image enhancement etc.