 |
|
|
|
|
|
 Title: |
US6246777:
Compression-tolerant watermarking scheme for image authentication
[ Derwent Title ]
|
| Country: |
US United States of America
|
| |
| Inventor: |
Agarwal, Saurabh; New Delhi, India
Aggarwal, Alok; Chappaqua, NY
Bassali, Harpal Singh; New Delhi, India
Chhugani, Jatin; New Delhi, India
Dubey, Pradeep Kumar; New Delhi, India
|
| Assignee: |
International Business Machines Corporation, Armonk, NY
other patents from INTERNATIONAL BUSINESS MACHINES CORPORATION (280070) (approx. 44,393)
News, Profiles, Stocks and More about this company
|
| Published / Filed: |
2001-06-12
/ 1999-03-19
|
| Application Number: |
US1999000273055
|
| IPC Code: |
Advanced:
G06T 1/00;
Core:
more...
IPC-7:
G06K 9/00;
|
| ECLA Code: |
G06T1/00W6C;
|
| U.S. Class: |
Current:
382/100;
Original:
382/100;
|
| Field of Search: |
382/100,232
380/210,287,54
|
| Priority Number: |
| 1999-03-19 |
US1999000273055 |
|
| Abstract: |
A verification system for still images that embeds a watermark so that no visual artifacts are created in the images and thus maintains the visual quality of the image. The algorithm embeds information in an uncompressed image so as to later detect the alteration of the image, as well as the location of the alteration. The embedding of information into a source image is based on a defined mapping process. An image plane consists of macroblocks, which are themselves comprised of microblocks. A code is embedded corresponding to the value of this image property in each macroblock. The specific sequence of microblocks used for embedding this information in the watermarking image plane is a unique function of this property for the corresponding set of microblocks in the indexing image plane. This information can be later decoded from the stamped image. The watermark is embedded by combining the pixel values of the image with the watermark. The watermark is altered if the image is altered.
|
| Attorney, Agent or Firm: |
McGuireWoods, LLP ;
Kaufman, Esq., Stephen C. ;
|
| Primary / Asst. Examiners: |
Johns, Andrew W.; Nakhjavan, Shervin
|
| INPADOC Legal Status: |
Show legal status actions
|
| Family: |
None
|
First Claim:
Show all 27 claims |
Having thus described our invention, what we claim as new and desire to secure by Letters Patent is as follows:
1. A method for embedding a watermark onto a digitized image, comprising the steps of:
- calculating a secret key used for embedding the watermark;
- splitting the digitized image into constituent planes;
- splitting each constituent plane into a plurality of microblocks based upon the secret key, the microblocks having a shape of a rectilinear polygon;
- grouping the microblocks into a plurality of macroblocks based upon the secret key, the macroblocks being a group of microblocks; and
- watermarking each macroblock while diffusing the error.
|
| Background / Summary: |
Show background / summary
|
| Drawing Descriptions: |
Show drawing descriptions
|
| Description: |
Show description
|
| Forward References: |
Show 84 U.S. patent(s) that reference this one
|
