| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that it is difficult to detect a watermark from an image, to which a complicated attack such as re-compression coding is applied, or to appropriately embed a watermark into such an image. <P>SOLUTION: Disclosed is an electronic watermark system utilizing a degraded source image, wherein the source image is used to simulate image processing caused by an attack, thereby eliminating unwanted error in electronic watermark detection. Namely, on the basis of an original method for detecting an electronic watermark only from a single check target image without any source image, unknown image processing contents are known by analogy while utilizing a source image and a degraded image is created. A differential between the degraded image and the check target image is created and an electronic watermark image is emphasized so as to be utilized for electronic watermark detection. Furthermore, the concept is also applied also in embedding and a strength of embedding in a portion, where noise is generated, is controlled, so that the electronic watermark can be embedded at a suitable position with a suitable strength. <P>COPYRIGHT: (C)2010,JPO&INPIT |
