An object of the present invention is to provide an electronic watermark embedding apparatus, an electronic watermark embedding method, a record medium having an electronic watermark capable of securely detecting the watermark in the case of performing the noise reduction process or data compression...http://www.google.com.au/patents/US20040022412?utm_source=gb-gplus-sharePatent US20040022412 - Electronic watermark embedding apparatus, electronic watermark embedding method, record medium having electronic watermark and manufacturing method of record medium
