摘要
提出了一种基于双树复数小波变换的特征点数字水印算法。对图像做三级双树复数小波变换,用F rstner算子提取图像低频子带中的特征点,根据复数小波变换的系数特点,通过修改相应的高频系数来实现水印信息的调制嵌入,提取水印信息的同时能够近无损恢复原始载体图像。算法兼顾了水印的鲁棒性和不可见性,能够有效抵抗剪切、平移、旋转等几何攻击,对线性拉伸、低通滤波等攻击也具有一定的鲁棒性。
This paper presents an image feature points watermarking scheme based on Dual-Tree Complex Wavelet Transform.It firstly calculates three Complex Wavelet Transform of the origin image,then uses Frstner operator extracting the feature points in low-frequency sub-band.According to the characteristics of complex wavelet transform coefficients,it can implement the watermark modulation embedding by modifying the corresponding high-frequency coefficients.When the watermark is extracted,the original carrier image can be near-lossless recovered at the same time.This algorithm has both robustness and invisibility,can effectively resist cropping,translation,rotation and other geometric attacks,and also has some robustness to linear stretching and low-pass filtering attacks.
出处
《海洋测绘》
2011年第1期39-42,共4页
Hydrographic Surveying and Charting