【摘要】 为提高图像盲水印抗几何攻击的能力,提出了一套基于图像特征的水印嵌入方案。首先利用具有几何不变性的Harris算子检测出图像特征点,然后在每块由特征点生成的Delaunay三角网上采用一种基于小波系数显著性差异调制量化方式进行水印的嵌入和检测。该嵌入水印算法的思想是通过比较每组小波系数的显著性差异值和所有组的平均显著性差异值的方法来量化每一组块的最大小波系数。实验结果表明,该方法不仅对压缩、滤波等常见攻击具有稳健性,同时对旋转、缩放、变形等几何攻击也具有较好的稳健性。更多还原

【Abstract】 To increase the ability of the watermarked image against the geometrical attacks in the blind watermarking applications,a digital image watermarking method based on image feature is proposed.First,feature points of image are extracted by geometry invariant Harris operator,then,on the Delaunay tessellation which is divided by this set of points,an efficient watermarking method based on significant difference of wavelet coefficient quantization is adopted to embed and detect the watermark.The idea of this watermarking method is that the local maximum wavelet coefficient in a block is quantized by comparing the significant difference value in a block with the average significant difference value in all blocks.The results of experiment show that the method is able to withstand a variety of attacks including JPEG compression,noise addition and common geometric attacks such as rotation,scaling and shift.更多还原