基于提升小波的多功能彩色数字图像双水印算法

摘要

基于彩色图像和提升小波的特性,提出一种新的多功能数字图像双水印算法.通过提取原始RGB图像的R、G、B三个色彩通道,在蓝色分量B的低频系数上嵌入版权水印；根据绿色分量G生成认证水印,嵌入在量化后的提升小波系数上.不需考虑两种水印嵌入的顺序.实验结果表明,版权水印鲁棒性较强、透明性较好,认证水印可以精确进行图像篡改检测和定位,实现多功能水印技术.%A new multifunctional double-watermarking algorithm of digital image is proposed based on the characteristics of colour image and lifting wavelet. Through extracting three colour channels of R, G, B from primitive RGB image, the new algorithm embeds copyright watermark in low frequency coefficient of blue component B; Then it generates authentication watermark according to green component G and embeds it in lifting wavelet coefficient. There is no need to consider the sequence of the embedment of two kinds of watermarks. Experimental results show that the copyright watermark has good robustness and imperceptibility, and the authentication watermark can realise tamper detection and location precisely as well, which achieves multifunctional watermark technique.