Patent ID: 6718045
Filing Date: 2004-04-06
Classification: G06T,H04N

Abstract:
Method of inserting a watermarking signal (w) in a set (X) of coefficients (Xi) representing a digital image (I), in which at least one subset of coefficients is modified by said watermarking signal (w), said method comprising, for each representative coefficient (Xi) to be modified, the following steps:determining a neighbourhood (V(Xi)) of said representative coefficient (Xi) to be modified, in the image (I); selecting a neighbourhood (Vsimd) in a dictionary of neighbourhoods representing coefficients representing said image (I), according to a predetermined criterion of similarity with said neighbourhood (V(Xi)) of said representative coefficient (Xi); and modifying said representative coefficient (Xi) as a function of the watermarking signal (w) and a predetermined masking data item (M(Vsimd)) representing the masking effect on a watermarking signal of said neighbourhood (Vsimd) selected from the dictionary.