一种新的非对称数字水印算法

基于离散Hartley变换提出了一种数字水印新算法．参考水印的能量在离散Hartley变换域中被重新分布，从而产生不同的嵌入水印，这些水印和参考水印均有相同的相关性．该算法可以利用一个参考水印检测不同的嵌入水印，但嵌入水印之间却不能互相认证．通过比较互相关系数值和选定的判决门限，来确定水印是否存在．此外，该算法针对实数数据处理，这与复数运算处理相比提高了计算效率．

Asymmetric digital watermarking algorithm based on DHT

An Asymmetric digital watermarking algorithm is proposed,based on the discrete Hartley transform(DHT).The energy of the reference watermark is redistributed in the DHT domain to get embedding watermarks.They have the same correlation with the reference one.The embedding watermarks can be detected by the reference one,but not by one another.To decide whether the watermark is present or not,the detector compares the correlation coefficient with the decision threshold.In addition,the proposed algorithm deals with real numbers,which increases the computing efficiency compared with those dealing with complex numbers.