大多数数字水印方法在水印嵌入的时候都是对原始图像信息作了一定的修改，这样使鲁棒性和安全性受到限制。零水印不需要修改原始图像的任何信息，有更好的透明性。本文提出了一种基于整数小波提升方案和对数极坐标映射(LPM)的零水印算法。首先将水印图像进行置乱，对载体图像进行缩放归一化，然后进行对数极坐标映射(LPM)，再进行一级整数小波提升，利用分解后的低频子图和置乱后水印图像构造密图，提取时利用密图来提取水印，增强了水印的透明性和安全性。

In the most existing methods of digital watermarking, authors modify more or less the original image data for embedding watermarks，which limits the robustness and security. The transparency of watermarks can be improved by zerowatermarking since it need not modify the original image information. In this paper, a zerowatermarking algorithm based on integer wavelet and LPM is proposed. We get the secret image through the scrambled watermarks and low frequency sub images after LPM and lifting wavelet transformation. The watermarked image can be extracted from the secret image. This algorithm improves the transparency and security.