基于彩色分量的数字图像水印

COLOR IMAGE WATERMARKING BASED ON COLOR CHANNELS

提出了一种基于彩色图像色差分量离散余弦变换 (DCT)域下的数字图像水印算法。该算法通过修改两色差分量的DCT系数 ,将水印信号埋植到图像中 ,而在水印信息检测时 ,不需要原始图像以及其他额外的数据。经实验测试 ,该算法可以抵抗诸如JPEG压缩、低通滤波、降采样、放大和缩小以及裁剪等大多数图像处理方法的攻击 。

Digital watermarking have been proposed as a method for discouraging illicit copying and distribution of copyrighted material. Now, there are many watermarking schemes for still color images, but a few of them exploit color channel properties to embed watermark. We present an approach for embedding digital watermarking information into color channels DCT-domains in the image. We observe that the correlation value between the color channels DCT coefficients is satisfied with some kind of statistical regular, by means of this statistical regular, we can modify the selected sets of DCT coefficients to make the correlation values show specific distribution, so that we can embed a binary string into the image. Specifically, the embedded watermarking is extracted without resorting to original image and any other data sets. Experimental results demonstrate that the watermark is robust to most of the image and signal processing techniques, and also our schemes are shown to provide very good results both in terms of image transparency and robustness.