DCT与LSB相结合的彩色图像双水印算法研究

为了提高图像水印的嵌入信息量,提出一种LSB和DCT相结合的彩色图像双重水印算法。即将载体图像分解为R、G、B三个色彩分量,分别在R分量和G分量上嵌入水印,对第一重水印图像进行置乱加密,将其嵌入到经8×8分块DCT变换后的R分量中;G分量上的水印则采用空间域的最低有效位方法,先对原始水印进行扩展,再将其嵌入到G分量的各个点像素值的最低有效位。实验表明该算法能有效提高水印的嵌入量,满足数字水印不可见性和鲁棒性的平衡。

A dual watermark algorithm based on DCT and LSB

In order to increase the information embedded in a vector image,a color image watermarking algorithm based on DCT and LSB is proposed.First,the vector image is decomposed into R,G,B,three color components.R and G components are embedded watermark.For the first image watermark scrambling encryption,it will be embedded into the 8 x 8 partitioned optimal of R component after transformation.With the watermark lowest effective method in spatial domain,the watermark on G component will be embedded to G pixel values of the lowest effectie.Experiments show that,this algorithm is effective to improve the embedding quantity,it have good robustness to such attacks as noise and compression.