Electronic watermark embedding method, device, and program, and electronic watermark detecting method, device, and program

摘要

A digital watermark embedding apparatus for embedding information, as digital watermark, into an input signal having dimensions equal to or greater than N (N is an integer equal to or greater than 2) and a digital watermark detection apparatus for detecting the digital watermark are disclosed. The digital watermark embedding apparatus generates an embedding sequence based on embedding information, generates a N-1-dimensional pattern based on the embedding sequence, generates N-dimensional embedding pattern by modulating a periodic signal according to a value on the N-1-dimensional pattern, and superimposing the embedding pattern in the input signal and outputs it. The digital watermark detection apparatus measures a component of a predetermined periodic signal in a direction of a dimension of the input signal to obtain a N-1-dimensional pattern, obtains a detection sequence from values of the N-1 dimensional pattern, and detects embedded digital watermark based on a size of correlation value between the detection sequence and an embedding sequence.