Patent ID: 7343025
Filing Date: 2008-03-11
Classification: G06T,H04N

Abstract:
1. A method of embedding a digital watermark on a wavelet lowest subband of an original image, the method comprising the steps of: wavelet transforming the original image into n levels; setting the wavelet lowest subband of the wavelet-transformed original image as a watermark embedment region; high-frequency filtering an original picture LL generating (i) index information designating a plurality of pixel positions within the watermark embedment region where the watermark is to be embedded, and (ii) a sequence of watermark values to be embedded in said pixel positions, respectively; calculating an embedment strength λ for each said pixel position of the watermark embedment region, considering a variance degree of an original picture LL for each said pixel position, selectively altering the original picture LL selectively embedding the watermark at each said pixel position with the selectively altered original picture LL