DEVICE AND METHOD FOR EMBEDDING INFORMATION AND READING INFORMATION, DIGITAL WATERMARK SYSTEM AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide a digital watermark system by which information is surely and easily reproduced from an image, in which information is embedded, without using a standard image even when that image is changed. SOLUTION: An element information extracting part 13 extracts the element information of a character from the image data of a document acquired by a main information input part 11. On the basis of this element information, an element information converting part 17 generates sub-information showing the size relation of rectangular areas surrounding characters in the document with minimum areas and changes the element information so that a copyright code acquired by a sub-information input part 15 can be matched with the prescribed part of the sub-information. A main information reconstituting part 18 changes image data on the basis of the changed element information and a main information output part 19 prints the document expressed by the changed image data. When the element information extracting part 13 extracts the element information from the document in which the copyright code is embedded, a sub-information reading part 20 extracts the sub-information from the extracted element information and the prescribed part of that sub-information is displayed by a sub-information output part 21 as a copyright code.