彩色照片中隐藏水印信息的分析与实现

针对利用数字水印技术进行证件真伪鉴别的应用背景,提出一种在证件的彩色照片中隐藏水印信息的方法,通过分析证件上的彩色照片在证件制作、使用以及鉴别过程中经受的三种主要攻击,提出在彩色图像的L*a*b*颜色空间的L*亮度分量中嵌入水印,将预测滤波器融于空域水印算法,自然鲁棒的水印模式用于对抗中轻度的几何失真以及局部的、小的非线性几何变形,并采用基于Hausdorff distance的方法校正大的几何失真的水印图像。实验结果表明本文水印算法对打印扫描攻击具有鲁棒性。

Analysis and realization of watermaking hiding in color picture

For the watermarking applied in certificate verification,a method that hiding information into pictures in certificate was proposed.Aiming at three main distortions during the process of certificate manufacture,use and verification,the prediction error filter used in L*component of color image's L*a*b*space.A kind of naturally robust watermark pattern is applied to resisting the local and small nonlinear distortion.The bigger geometric distortions are corrected by image registration based on Hausdorff distance.Experimental results show that the proposed method achieves robustness against printing and scanning.