发明名称 |
Method of authenticating digital-watermark pictures |
摘要 |
An extraction process includes the steps of carrying out a geometric transformation on a picture being inspected to transform the size of the picture being inspected into a reduced scale of an original picture; creating a plurality of degraded original pictures with different types each obtained as a result of degradation of the original picture; creating a plurality of differential pictures by subtraction of the degraded original pictures with different types from the picture being inspected with a transformed size to cancel degradation components in the picture being inspected with a transformed size; and extracting the information corresponding to the authentication information.
|
申请公布号 |
US6418232(B1) |
申请公布日期 |
2002.07.09 |
申请号 |
US19990383199 |
申请日期 |
1999.08.26 |
申请人 |
HITACHI, LTD. |
发明人 |
NAKANO KAZUNORI;TAGUCHI JU&NACUTE,ICHI;YOSHIURA HIROSHI;ECHIZEN ISAO;KUROSU YUTAKA |
分类号 |
H04N1/387;G06T1/00;G06T3/00;G09C5/00;H04L9/32;(IPC1-7):G06K9/00 |
主分类号 |
H04N1/387 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|