公开(公告)号：JP2000224411A

公开(公告)日：2000-08-11

申请号：JP2000015753

申请日：2000-01-25

Applicant: IBM

Inventor： DAVID H JAMESON ,  CHARLES P TRESSER ,  CHAI W WOO ,  STEVEN R ABRAMS ,  SHUMUEL WINOGRAD

IPC: G09C1/00 ,  G06F1/00 ,  G06F11/00 ,  G06F11/10 ,  G06F12/14 ,  G06F21/00 ,  G06F21/24 ,  G06T1/00 ,  G11B20/00 ,  G11B20/18 ,  H03M13/01 ,  H04L9/30 ,  H04N1/32 ,  H04N1/387 ,  H04N7/08 ,  H04N7/081

Abstract: PROBLEM TO BE SOLVED: To recognize whether or not a recording object is true or whether or not it is performed by a true author or both of them by hiding an additional message inside an error correction code for the significant contents of a digital message. SOLUTION: In this method, all authentication data A201 are hidden in the error correction code(ECC) 210 used for performing recording. A code to be used for generating three sets (A, W and D) 205 can be based on ciphering 200 and authentication message A is turned to a coded message corresponding to a pair (W and D) instead of the general tacit relation of the authentication data A201 and an optional data set W202 and an auxiliary data set D203 to be recorded. The meaning of the recorded object is not influenced, a standard reader is not only detected but also not influenced and the truthfulness or propriety or both of recording is recognized.

公开(公告)号：SG97162A1

公开(公告)日：2003-07-18

申请号：SG200005113

申请日：2000-09-08

Applicant: IBM

Inventor： GAURAV AGGARWAL ,  PRADEEP KUMAR DUBEY ,  ASHUTOSH KULSHRESHTHA ,  MARCO MARTENS ,  CHARLES P TRESSER ,  CHAI WAH WU

IPC: G06T1/00 ,  H04N1/32 ,  G06T9/00

Abstract: A method is presented for marking high-quality digital images with a robust and invisible watermark. It requires the mark to survive and remain detectable and authenticatable through all image manipulations that in themselves do not damage the image beyond useability. These manipulations include JPEG "lossy" compression and, in the extreme, the printing and rescanning of the image. The watermark also has the property that it can detect if the essential contents of the image has changed. The first phase of the method comprises extracting a digest or number N from the image so that N only (or mostly) depends on the essential information content, such that the same number N can be obtained from a scan of a high quality print of the image, from the compressed form of the image, or in general, from the image after minor modifications (introduced inadvertently by processing, noise etc.). The second phase comprises the marking. This can be done in form of an invisible robust watermark, or in form of some visible signature or watermark.