| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that, conventionally, there exists a risk that confidential information is left on an output tray of a printer and the information leaks to a user who is not normally allowed to access the confidential information. <P>SOLUTION: In a printer, output time information is embedded by digital watermarking during printing in order to discard an output manuscript copy as a countermeasure against information leakage when the output manuscript copy is left on an output tray for a fixed period of time. A keeper of the printer scans the left manuscript copy and extracts the output time information so as to judge an elapsed time. Then, the keeper automatically judges whether discard the left manuscript copy. If required, the keeper gives a discard notice to a person in charge for the copy. <P>COPYRIGHT: (C)2009,JPO&INPIT |
