发明名称 |
Method of extracting digital watermark information and method of judging but value of digital watermark information |
摘要 |
A digital watermark information is extracted from geometrically deformed image without using a calibrating digital watermark. Pixel data at positions predetermined in an X-Y coordinate used when embedding the watermark is extracted from image data in which the digital watermark has been embedded for given pixel data and compared with a reference value to determine whether the watermark has been embedded in the pixel data concerned or not. This processing is repeated until it is confirmed that the information is embedded in the pixel data concerned, while applying geometric deformation to the image data.
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申请公布号 |
US6456727(B1) |
申请公布日期 |
2002.09.24 |
申请号 |
US20000523523 |
申请日期 |
2000.03.10 |
申请人 |
HITACHI, LTD. |
发明人 |
ECHIZEN ISAO;YOSHIURA HIROSHI;KUROSU YUTAKA;ANZAI KOUSUKE |
分类号 |
G06T1/00;(IPC1-7):G06K9/00 |
主分类号 |
G06T1/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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