基于QDCT和HVS的双彩色图像水印算法

针对水印中信息容量、不可见性和鲁棒性相互制约的问题,文中提出了一种基于QDCT和HVS的双彩色图像水印算法。该算法首先将彩色载体图像和彩色水印图像进行QDCT;然后根据HVS的特性决定水印信息的嵌入位置与嵌入强度,并结合广义Arnold变换和冗余嵌入策略, 将水印QDCT系数嵌入到载体图像QDCT系数的实部和虚部。实验结果表明,通过该算法嵌入水印后的彩色图像在PSNR为35 dB时,在常见攻击下提取出的水印大部分NC值高于0.95,水印信息具有更好的不可见性与鲁棒性。

Dual Color Image Watermarking Algorithm Based on QDCT and HVS

Aiming at the mutually restricted problem of information capacity, invisibility and robustness in watermarking, a dual color image watermarking algorithm based on QDCT and HVS was proposed. With this algorithm, a colored carrier image and a colored watermarking image were subject to QDCT. The embedding location and strength of watermarking information were decided based on the characteristics of HVS. Based on the generalized Arnold transform and redundant embedding strategy, the QDCT coefficient of the watermarking image was embedded into the real part and imaginary part of the QDCT coefficient of the carrier image. The experiment result showed with this algorithm, most of NC values of the watermark extracted under common attacks were higher than 0.95 and the watermark information possessed better invisibility and robustness for the colored watermark-embedded image when PSNR was 35 dB.