Patent 7356699 was granted and assigned to NEC Corporation on April, 2008 by the United States Patent and Trademark Office.
In the electronic watermark detection device, an electronic watermark detection unit receives input of a DCT coefficient and a picture start from a preprocessing unit to detect an electronic watermark inserted into image data and indicative of copyright information or the like, a detection result adjustment unit receives input of a picture start from the preprocessing unit and input of a detector result and a detector interruption from the electronic watermark detection unit to count the number of pictures, as well as generating and outputting a detection interruption according to the detection result, and an interruption processing unit receives input of a detection result and a detection interruption from the detection result adjustment unit to generate an interruption signal according to a system, as well as outputting the detection result.