Research Of Color Image Digital Watermarking Based On Color Clustering Segmentation And Transform Domain

In recent years, many digital products are illegally copying and tampering.Digital watermarking technology has solved such problems effectively. In the aspect of copyright protection of digital products, it has a very good effect. In view of this,this paper made some research on digital watermarking technique.Firstly, the paper introduces some basic theories related to digital watermarking,the main problems such as the concept, and classification of digital watermarking.Then the paper introduces the relevant theories of digital watermarking based on DCT.Secondly, this paper introduces three technology of image segmentation, RGB,CMYK and L??. Because of the embedded color watermark in color image, the watermark has great influence on the original image. There is also a drawback in terms of digital watermarking imperceptible. One innovative method is raised in this paper. This method is that the right areas are chosen to embed the watermark after separating the image. In the aspect of image segmentation, the color clustering segmentation method based on space L?? is applied, because of the miscellaneous kinds of color in image. After choosing appropriate divided image, the choice of the area where the watermark is embed can be made according to the contrast of color in divided areas and watermark image. To be convenient, A great rectangular area has been chosen as the area where the watermark embed among the above specific area.Finally, this paper proposes a digital-watermark algorithm which is base on segment DCT. This watermark algorithm respectively presents two methods and make experiments on these. One method is that embedding watermarks in parts of areas in a whole image. Another one is to directly embed watermark in a whole image. Then,comparing these two methods to determine the advantages and disadvantages in watermark algorithm. The experimental results showed that the watermark algorithm which is declared in this paper has obvious superiority in imperceptible area. What’s more, we take tests on the robust of segment-DCT-based watermark algorithm. The results show that this watermark algorithm has strong robust for common attacks.