Patent ID: 6072888
Filing Date: 2000-06-06
Classification: G06Q,G06T,G07D,G07F,H04N

Abstract:
A method of encoding N-bits of auxiliary data within a digital image so that the encoded data is substantially imperceptible, N being at least two, each of said bits of auxiliary data having first or second values, wherein:the digital image is presented as rows of pixels, each pixel having at least a luminance value associated therewith;the encoding results in increasing the luminance values of at least certain of said presented pixels;the encoding further results in decreasing the luminance values of at least certain others of said presented pixels;and wherein a change of a single of said N-bits of auxiliary data between said first and second values is manifested as changed luminance in plural non-contiguous pixels located in plural non-contiguous rows of said digital image.