| 摘要 |
PURPOSE:To make optimum MTF corrections suitable to the response of an input system by using two-dimensional digital filters which have various characteristics and selecting a two-dimensional filter to be processed optionally according to filter specification. CONSTITUTION:When an MTF correcting circuit 11 corrects the image information BS of an original read by a scanner by two-dimensional digital filter processing, two-dimensional digital filters having various characteristics are used and an optional two-dimensional filter is selected according to a command FCS for filter specification suitable to the response of the input system. Further, the response of the input system for image information is different, scanner by scanner, and even one scanner differs in response between the main scanning direction and subscanning directions. For the purpose, this system uses plural two-dimensional filters (including Laplacean filters) suitable to responses of various input systems and uses the best two-dimensional filter selectively for image reading. |
