| 摘要 |
PURPOSE:To decrease the deterioration of a picture due to variable power processing by MTF-correcting an image data after or before the variable power based on MTF correction calculation data corresponding to designated magnification ratio. CONSTITUTION:An original image data read by a scanner SCR is subjected applied with a variable power processing and MTF-correction in the main scanning direction X by a variable power processor consisting of a latch 25, a data distributor 26, RAMs 1 and 2, a data selector 27, a main scanning direction variable power computing element 28, a microprocessor 35, a RAM 3 and sampling circuits 64 and 65 through a shading correction circuit 24. Thereafter the original image data is applied with a variable power processing and MTF- correction in the subscanning direction Y by a subscanning variable power computing element 29. For the MTF correction, correction coefficients corresponding to magnifications are set beforehand, and the MTF correction is applied by speerfying one of the coefficient with the magnifications. A variable power image data goes through a binarization circuit 30 or a gradation processor 31 and is outputted to a printer PRT. |
