摘要
本文提出了一种脊波域的水印嵌入和盲检测算法.脊波变换(ridgelet transform,RT)具有方向敏感性和各向异性的特点,它可获得具有直线特征的图像的稀疏表示.对这类图像进行多尺度脊波变换后,其中最重要的脊波系数代表了图像能量最集中方向的特征,即沿着图像的边缘方向的特征.对一般含有曲线边缘或纹理的图像,可将图像分成小块,将曲线近似作直线处理.然后,对每个小块进行多尺度脊波变换,选择出脊波系数能量大于某个阈值的方向,并在该方向的中频脊波带嵌入水印.实验证明,水印使用该嵌入方法具有很强的鲁棒性和透明性.
A digital image watermark embedding and extracting algorithm is presented based on the mulfiscale ddgelet transform （RT） which can efficiently represent image with linear singularities. The RT transform also has directional sensitivity so that among the transformed coefficients the most significant ones represent the most energetic directions of straight edges in an image. To get straight edges the digital image with curvilinear edges or texture is partitioned into small pieces. Then the pieces are treated by RT and the most energetic directions of pieces whose energy are greater than some threshold are selected. And eventually the watermarks are embedded in the the middle fidgelet subband of the selected directions. Different noises with different SNR are added to the watermarked image in the experiments and the results prove robustness and transparency.
出处
《电子学报》
EI
CAS
CSCD
北大核心
2007年第9期1804-1808,共5页
Acta Electronica Sinica
关键词
图像处理
数字水印
脊波变换
信息检测
image processing
digital watermarking
ridgelet transform
signal extraction
