Patent ID: 6567532
Filing Date: 2003-05-20
Classification: G06T

Abstract:
A method for extracting an embedded message from a digital image, the embedded message being formed by arranging message bits in predetermined locations represented by a message template, convolving the message with a random phase, flat Fourier amplitude carrier to form a dispersed message and tiling the dispersed message over the image, comprising the steps of:a) locating the tile boundaries in the digital image; b) correlating a tile with the carrier to extract the embedded message; c) forming a multiplier A that is inversely proportional to the noise in the extracted message; d) multiplying the embedded message by A to form a weighted embedded message; e) repeat steps b) to d) for a second tile to generate a second weighted embedded message; f) summing the weighted embedded messages to form a summed weighted embedded message; and h) extracting the message bits from the summed weighted embedded message.