Adaptive 2-Dimension Image Watermarking Algorithm
自适应二维数字水印系统

The digital media, including text, image, graphics, audio and video etc., has become a main way for information communication along with the popularization of Internet and the development of multimedia techniques. People can get almost information through the Internet. But this gives rise to serious problems including wide spread copyright violation, illegal copying, easy forging etc. How to provide copyright protection has drawn extensive attention in recent years. As a main method for copyright protection, the techniques of watermarking, have been widely studied and applied. In this paper, we proposes an adaptive 2 dimension image watermarking algorithm in space domain with gray image's watermark. In order to embed the image's watermark, we split the image's watermark into blocks and transform them into DCT domain. Then quantize their DCT coefficients and adjust them. Finally, take out the parts of DCT coefficients from each block to constitute the watermark. By using the human visual system, we split the original image into blocks and classify them. According to the classification, the watermark components with different strength are embedded into cover image. The experimental results show our algorithm has very excellent effect. Finally, we make a discussion on some open problems and point out possible directions for further research.