A Digital Watermarking Algorithm for Color Images Through Fisher Discriminant Analysis
Yao Zhi · Mini-micro Systems · 2004
A improved digital watermarking algorithm,which hides the watermarking signals in the blue component of color images, is presented in this paper.A watermarking signal derives by concatenating a q bit binary sequences and a m bit binary watermarking sequences.In the extract watermarking method, a set of n dimension patterns containing training patterns and simulating patterns is collected from adjacent positions around each embedded pixel of the watermarked image.After Fisher discriminant analyzing, the dimension of all patterns reduce to one and a threshold is gained by training patterns.Therefore we can almost exactly classify the watermarking signals {0,1} from the watermarked images by comparing the simulating patterns with without original image.The experimental results show the robustness of the digital watermarks by this algorithm.