Electronic watermark embedding device, electronic watermark detection device, method thereof, and program

摘要

A digital watermark embedding apparatus for embedding digital watermark information by superimposing macroblock patterns on an image is disclosed. The digital watermark embedding apparatus: spreads input digital watermark information to obtain an embedding series having a length corresponding to a number of pixel blocks of a macroblock pattern; selects at least a frequency from among predetermined plural frequencies according to a term value of the embedding series corresponding to a position of a pixel block in the macroblock pattern, and sets a waveform pattern corresponding to the selected frequency as a pixel of the pixel block; and amplifies, with an embedding strength value, the macroblock pattern on which a waveform pattern is superimposed on each pixel block by the waveform pattern setting unit, and superimposes the macroblock pattern on an input image like a tile.