Title:
DIGITAL WATERMARK EMBEDDING METHOD AND DIGITAL WATERMARK DECODING METHOD AND DEVICE
Document Type and Number:
Japanese Patent JP3942759
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a digital watermark embedding and decoding technique which has sufficient resistance with respect to various kinds of attacks at the time of embedding and decoding a digital watermark by using orthogonal transformation.
SOLUTION: Plural blocks are segmented from an original image and are subjected to orthogonal transformation for each block, corresponding coefficients between the adjacent blocks are compared, and the size relation of the both coefficients is changed according to bit information to be embedded. Also, bit information to be embedded is constituted as a basic pattern prepared by a concentration pattern method, and this is repeatedly embedded in the image data. Thus, resistance strength can be improved by repeatedly embedding the patterned bit information.
More Like This:
| JPH09275502 | FACSIMILE EQUIPMENT |
| JP2005039686 | ELECTRONIC WATERMARK EMBEDDING SYSTEM/ELECTRONIC WATERMARK VERIFICATION SYSTEM |
| JP4406589 | Network printing system |
Inventors:
Koshio Matsui
Application Number:
JP1567499A
Publication Date:
July 11, 2007
Filing Date:
January 25, 1999
Export Citation:
Assignee:
Kowa Co., Ltd.
International Classes:
G09C5/00; G06F21/10; H04N1/387; G06T1/00; H04N1/32; H04N19/102; H04N19/136; H04N19/176; H04N19/186; H04N19/196; H04N19/467; H04N19/60; H04N19/625; H04N19/85; (IPC1-7): H04N1/387; G06T1/00; G09C5/00; H04N7/30
Domestic Patent References:
| JP10234012A |
Foreign References:
| WO1997049235A1 |
Attorney, Agent or Firm:
Takao Igarashi
Takashi Shimoide
Hiroshi Ichikawa
Takashi Shimoide
Hiroshi Ichikawa