| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To correctly detect watermark information with small calculation cost for extracting the watermark information by photographing a printed watermarked image, even if local nonlinear distortions are produced. <P>SOLUTION: The electronic watermark detector comprises an image reader for reading image data, an image shape approximating unit for approximating the shape of the image data to a polygon, an embedding position estimator for estimating the embedded position of the watermark information, based on the shape of the shape-approximate image, a detection filter generator for generating a detection filter, based on the shape of the shape-approximated image, and a watermark information detector for detecting the watermark information, based on the embedded position and the detection filter, thereby detecting the electronic watermark. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
