Electronic watermarking system capable of providing image data with high secrecy

摘要

In an electronic watermarking device for inserting an electronic watermark into an original image, discrete cosine transformer carries out discrete cosine transform of a partial block of the original image, inserting unit inserts electronic watermarking data into an output of the discrete cosine transformer, inverse discrete cosine transformer carries out inverse discrete cosine transform of an output of the inserting unit, and coordinate converter which has coordinate conversion data carries out coordinate conversion of an output of the inverse discrete cosine transformer by the electronic watermarking data and the coordinate conversion data.