基于混合域的自适应扩频肓鲁棒水印算法

Blind spread spectrum robust watermarking algorithm based on self-adaptation of mixed domains

针对当前数字水印技术中基于单一变换域所存在的问题,提出了一种基于DWT与DCT相结合的自适应扩频肓检数字水印算法。在载体图像被转入YIQ空间后,首先对Y分量小波分解,再对中低频子带做分块DCT变换,从而有效地降低单一变换所带来的负面影响。算法在对水印图像进行Hamming编码与混沌调制后,根据人眼视觉特性对各系数子块分别计算水印自适应强度因子实现了水印的自适应嵌入。将仿真结果与基于单一变换域的算法进行比较,结果表明了该算法具有更好的鲁棒性。

Aiming at the problems of digital watermarking based on single domain transformation,a blind spread spectrum robust water-marking algorithm based on DWT and DCT domains is presented.The Y component of color image is decomposed by DWT first,and then some medium and low frequency sub-bands are performed by DCT again so as to reduce the negative effects of transformation based on single domain.The factors of embedding intensity are computed by integrating multi-sensing factors of HVS.At last,the binary image is embedded adaptively after Hamming coded and chaos modulated.The simulation results prove the proposed algorithm has better robustness then those based on single domain.