一种基于小波变换和最优量化的数字水印技术

A watermark embedding scheme based on wavelet transforming and optimal quantifying

提出了一种基于小波变换和最优量化的数字水印嵌入算法。该算法首先对图像进行小波变换,然后对变换系数进行最优量化处理,再嵌入水印信息。水印的提取过程不必借助于原始图像。实验表明,对加入水印的图像进行图像退化处理后,仍然能方便、可靠地检测出嵌入的水印信息。在低频区域嵌入低强度的水印信息,可以同时保证嵌入水印信息的鲁棒性和不可见性。

A watermark embedding scheme in the still image is proposed. It is based on wavelet transforming and optimal quantifying. First, the image is divided into subimages of different resolution level with wavelet transform. Then the wavelet transform coefficients are quantified by optimal quantifier. Finally the watermark is embedded. The original image is not required in the procedure of extracting the watermark. The experimental results show that it is easy and reliable to extract the watermark from degenerated image. Embedding weak watermark in low frequency region can guarantee the robust and invisible of watermark information at the same time.