Apparatus and method for embedding/unembedding supplemental information

Abstract

A supplemental information embedding apparatus having a device for capturing image data, a first memory for storing image data indicating the presence of copyright protection, a first encoder for encoding the image data obtained by the image capturing means to a first format digital image data by n stages of processing (n is a positive integer greater than or equal to 2), a second memory for storing the first format digital image data produced in the digital image data producing means, a second encoder for encoding the image data indicating the copyright data supplied from the image capturing device or the first memory to a second format digital watermark by i stages of processing (i is a positive integer less than n), a third memory for storing the second format digital watermark encoded by the second encoder, a decoder for decoding the first format digital image data stored in the second memory up to a desirable stage of decoding, a divider for dividing the second format digital watermark stored in the third memory into predetermined format blocks, an embedder for dispersively embedding the blocks of the digital watermark into the image data encoded up to i stage by the first encoder or the irate data decoded up to i stage by the decoder, a third encoder for encoding the image data obtained by the embedder by exerting operations on and after j stage (j=n−1) of encoding so as to produce the first format digital image data, and a fourth memory for storing the first format digital image data encoded by the third encoder.