基于二维DCT的双图像数字水印算法

数字水印技术为因特网上数字图像的版权侵犯、非法复制、泄密和完整性等问题提供了一种有效的解决途径。本文提出了一种基于二维DCT的双图像数字水印算法，该算法通过二维DCT变换将灰度图像植入色彩图像中，并通过滤波过程能将灰度图像抽取出来。实验证明，该算法的效果良好，稳健性强，植入的水印对剪裁、旋转、翻转、比例缩放和JPEG有损压缩都具有较强的免疫力。

A BI-IMAGE WATERMARKING METHOD BASED ON 2D-DCT

Digital watermarking techniques provide an effective means for overcoming serious problems of digital images on the Internet, including copyright violation, illegal copying and distribution, secret disclosing, integrity, etc. In this paper, the authors develop a bi-image watermarking method based on 2D-DCT, which embeds a grayscale image into a color image by using discrete cosine transform. The experimental results show that the proposed scheme works really well, the embedded watermark is effectively robust against various image processing operations such as cropping, rotation, flipping, scaling, JPEG lossy compression, etc.