一种新颖的自适应水印算法

Adaptive digital watermarking algorithm

目前有很多基于离散小波变换(DWT)的水印算法,但结合分形编码技术的很少。提出并实现了一种新的自适应水印算法。该方法能利用人眼视觉特性和分形误差,自适应控制水印的嵌入位置,能有效地改善水印图像的视觉质量;同时,也提高了水印系统的安全性。在低分辨率图像中嵌入水印,该方法效果较佳。实验结果表明,使用该方法嵌入的水印具有较好的不可感知性和鲁棒性,同时保证了较低的正向错误率。

Currently, there are many DWT（Discrete Wavelet Transform） based watermarking algorithms, but few of them discuss the issue in association with fractal image coding in wavelet domain. A new algorithm proposed by us can adaptively select locality to insert digital watermark to get better quality for image with watermarking and enhance the security of watermarking system, according to the characteristics of HVS（Human Visual System） and fractal image coding error. This algorithm performs well especially in low-resolution picture. The experimental results show that the algorithm makes watermark better invisible and robust, and keeps lower positive error ratio as well.