| 摘要 |
PURPOSE:To prevent the impropriety of an MTF correction and to further decrease a means necessary to execute the variable power calculation and the MTF correcting calculation by substituting to an MTF correcting variable power calculating formula to annex the MTF correction calculation to the interpolating calculation and executing simultaneously the variable power and the MTF correction. CONSTITUTION:A microprocessor 35 responds to an image reading starting instruction, reads a designated magnification ratio Rx%, instructs a scanner SCR to execute the image reading and a line synchronizing pulse LSYNC sets the data to show a designating magnification Rx% to an address counter 48. The original image data by the scanner SCR are serially supplied by a parallel 6-bit unit to a shading correcting circuit 24 for one line, one of the variavle power image data is specified at a variable power R by using an MTF correcting calculating formula to set a correcting coefficient(filter coefficient) in correspondence to the variable power by a main scanning variable power arithmetic device 28 and a sub-scanning variable power arithmetic device 29, and MTF-corrected before or after the variable power image data calculation. |
