| 摘要 |
PURPOSE:To obtain a half tone picture without having picture unevenness by converting the half tone picture signal of a low density component to a binary picture signal corresponded with a dot forming density pattern and converting the half tone picture signal of other that the low density component to the binary picture signal corresponded with a multi-valued density pattern. CONSTITUTION:The picture element data of a picture memory 62 assigned at an X address counter 63 and a Y address counter 64 is compared with the thresholds of matrix memories 65 and 66 assigned at a column counter 67 and a low counter 68 at each of digital comparator 69 and 70 and when it is larger than them, a black signal is outputted from the comparators 69 and 70. Either of the output signals from the comparators 69 or 70 is selected at a multiplexer 71 and it is sent to a laser printer 72 as the binary picture signal. When the low density level, for example, under 16 of a variable density picture signal component is converted to a binary picture out of the picture data inputted by the dot forming density pattern, so that it is converted to the binary picture at a density area prior to the generation of density unevenness, the density unevenness is suppressed to the utmost.
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