摘要： 根据图像小波变换系数的特点，提出一种以灰度图像为水印的新算法。宿主图像经过p级小波分解，将低频LLp系数值与加权后的水印灰度值相加，对变化的LLp系数值和没有变化的高频系数进行小波逆变换得到水印图像。实验结果表明，该算法使水印具有良好的不可见性、鲁棒性和低复杂性。

关键词: 信息安全, 水印图像, 小波块, 小波变换

Abstract: This paper proposes a new gray digital image watermark algorithm based on performances of wavelet transform coefficients. Host image is decomposed into p levels with wavelet, then LLp coefficients is added by scaled gray levels of watermark, then it takes the new LLp coefficients of host image and the unchanged DWT coefficients through wavelet conversely transforming to form watermark image. Experimental results show the algorithm make watermark be good at sightlessness, robustness and low-complexity.

Key words: information security, watermark image, wavelet block, wavelet transform

中图分类号: 

• TN918.74