DEVICE WHICH EMBEDS AND EXTRACTS ELECTRONIC WATERMARK INFORMATION, METHOD, AND PROGRAM THEREFOR

摘要

PROBLEM TO BE SOLVED: To stably extract electronic watermark information from a carrier signal even if the carrier signal receives a disturbance after the electronic watermark information is embedded. SOLUTION: A band-dividing part 110 divides a carrier signal xp(n) into a plurality of band carrier signals. Embedding parts 120-0 and 120-1 make band carrier signals X(ω0) and X(ω1) embedding-destination band carrier signals and perform wavelet transformation to the amplitude sequences of the embedding destination band carrier signals to generate wavelet coefficients. The embedding parts perform modulation to the wavelet coefficients by means of modulation signals m0 and m1 corresponding to electronic watermark information, and perform reversal wavelet conversion to the wavelet coefficients thus modulated to generate a band carrier signal in which the electronic watermark information is embedded. A band coupling part 130 combines the band carrier signal thus generated with another band carrier signal which the band-dividing part 110 outputs, and outputs it. COPYRIGHT: (C)2010,JPO&INPIT