基于图像边缘的自适应互补水印算法

Adaptive and complementary watermarking algorithm based on image edge

对图像数字水印的鲁棒性和不可见性进行了研究,提出了一种在图像边缘处嵌入数字水印的思想。利用Sobel算子新灰度值提取边缘特征点并自适应地确认水印嵌入强度。同时根据人类视觉系统的特性,在小波变换后的细节子带上嵌入互补性水印。实验结果表明,嵌入水印后的图像无明显质量下降,并且可以有效地抵抗压缩、滤波、噪声等各种攻击。证明了该基于图像边缘的自适应互补水印算法同时具有较好的鲁棒性和不可见性。

The invisibility and robustness of image watermarking are analyzed, a thinking of embedding digital watermarking in image edge is presented using new gray-scale of sobel operator to detecte feature points and confirm watermarking strength adaptively. Then according to characteristics of human visual system, embedded complementary watermarking into decomposed detail subbands of discrete wavelet transform. The experimental results displayed that the image embedded watermarking didn＇t drop in quality obviously, and could resist the compression, the filter, the noise effectively, and so on. So this adaptive and complementary watermarking algorithm based on image edge is proved to be good at both robustness and invisibility.