The Analysis Of Correlation Detection Based On Digital Watermarking

With the development of network technology, digital medias have been widely used and spread through the Internet. When people get onto the Internet they can conveniently spread, acquire and exchange information. At the same time many serious problems about the intellectual property right and the protection of copyright have been exposed, and then the digital watermark emerged as the times required.For the sake of judging the digital data whether or not contains brand watermark, we need a detect process. In the watermark detection, the first step usually is watermark extraction, and the second step is watermark adjudgement. We choose acorrelation detection threshold noted as^ρthr, then calculate the correlation value ρof the extracted watermark and reference watermark. If ρ ≥ ρthr, we can assure that digital data we detected contains the reference watermark.By investigating systematically watermark as well as detection technology, we find out in papers that judging whether or not containing given watermark depend exclusively on extracting watermark, however extracting watermark is extremely difficult without embedding algorithm. Papers defined correlativevalue as :The great improvement of the algorithm presented in papers is without extraction watermark in detective procession. But the detection threshold in the...