It makes full use of the multi-resolution of DWT and the energy compression of DCT and embeds grayscale image watermark in the even-uneven identity of DCT quanti-fying value by preprocessing.

• 它充分利用离散小波变换的多分辨率特性和离散余弦变换的能量压缩能力,将预处理后的灰度水印图像隐藏在原始图像DCT系数量化值的奇偶性中,在水印的提取过程中不需要原始图像的参与。