| 摘要 |
<P>PROBLEM TO BE SOLVED: To securely manage an electronic document file including a document and graphics. <P>SOLUTION: Hash data are generated from document data, and embedded in drawing data with an electronic watermark, and registered in an electronic document and drawing database 12 as an electronic document file. The electronic document file designated by a browser is read from the electronic document and drawing database, and first hash data are generated from document data in the file, and the hash data embedded in the drawing data in the electronic document file are detected as second hash data, and the first and second hash data are compared, and when those hash data are not matched, it is determined that the document data and/or drawing data in the electronic document file have been altered, and the browsing of the electronic document file is inhibited. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
