| 摘要 |
PROBLEM TO BE SOLVED: To prevent the remarkable drop of printing speed due to excess load on the CPU of a host computer when a forgery judgment processing by an electronic watermark is conducted in a printer driver. SOLUTION: Only when printing information inputted in a step S301 is image data of resolution exceeding 100 dpi (S302), an electronic watermark detection processing (S303) and a forgery prevention processing (S305) are conducted. Thus, the load on the decision processing is suppressed to be necessary minimum. |
