| 摘要 |
PURPOSE:To enable to obtain a picture clearer than an original picture especially for a fine meshed halftone photograph by making proper emphasis according to necessity on the edge part of an original picture in which various pictures are mixed. CONSTITUTION:Analog picture signals from a CCD line sensor 30 are density converted by an analog-LOG converting circuit 31 and then converted to digital signals of 6-8 bits by an A/D converter 32. Then, shading correction is made by a shading correcting circuit 33 by subtracting white plate shading data accumulated beforehand in a RAM. Smoothing in the direction of main scanning is made next by a smoothing circuit 34, and the edge part is emphasized by an edge emphasizing circuit 35. The data in which the edge part is emphasized are gamma converted by a gamma converting circuit 36 and then added to a dither circuit 37 and compared with dither threshold value, binary coded, and outputted. |
