Digital watermark embedding device, digital watermark detecting device, digital watermark embedding method, digital watermark detecting method, computer-readable recording medium containing digital watermark embedding program, and computer-readable recording medium containing digital watermark detecting program

摘要

A digital watermark embedding device includes a generating unit that makes use of a key random number which is input, and outputs a filter for determining a first band and a second band which represent at least a single pair of frequency bands in which a digital watermark bit is to be embedded; and an embedding unit that, when the digital watermark bit is to be embedded in a unit frame of a voice signal which is input, varies a sum of amplitude spectrum intensities of at least one of the first band and the second band in such a way that a first sum of amplitude spectrum intensities of the first band is greater than a second sum of amplitude spectrum intensities of the second band.