@article {18271,
title = {Rotation, scale, and translation resilient public watermarking for images using a log-polar fourier transform},
year = {2001},
month = {2001/08/28/},
abstract = {A method for detecting a watermark signal in digital image data. The detecting method includes the steps of: computing a log-polar Fourier transform of the image data to obtain a log-polar Fourier spectrum; projecting the log-polar Fourier spectrum down to a lower dimensional space to obtain an extracted signal; comparing the extracted signal to a target watermark signal; and declaring the presence or absence of the target watermark signal in the image data based on the comparison. Also provided is a method for inserting a watermark signal in digital image data to obtain a watermarked image. The inserting method includes the steps of: computing a log-polar Fourier transform of the image data to obtain a log-polar Fourier spectrum; projecting the log-polar Fourier spectrum down to a lower dimensional space to obtain an extracted signal; modifying the extracted signal such that it is similar to a target watermark; performing a one-to-many mapping of the modified signal back to...},
url = {http://www.google.com/patents?id=v4AIAAAAEBAJ},
author = {Bloom,Jeffrey A. and Cox,Ingemar J. and Miller,Matthew L. and M. Wu and Lin,Ching-Yung and Lui,Yui Man},
editor = {Signafy, Inc.}
}