| 摘要 |
PROBLEM TO BE SOLVED: To efficiently removing only moire components without deteriorating the resolution of a character by excluding averaging processing concerning an area judged to be character components and executing averaging processing for only an area judged to be moire components. SOLUTION: A digital multilevel picture signal temporarily stored in a line memory 15 is outputted by 2n+1 picture elements at a time from the leading picture element of one line by a bit selection circuit 14. A deciding circuit 17 compares an absolute value given difference by a differential circuit 16 and a threshold value Th outputted from a threshold value storage circuit 18 to output the output signal from the bit selection circuit 14 is outputted to an arithmetic circuit 19 as it is when the absolute value is smaller than this threshold value Th and to prevent the output signal from passing to the arithmetic circuit 19 when the absolute value is judged to be larger than the threshold value Th, namely to be character components. The arithmetic circuit 19 takes an average of the output signal and the signal selectively inputted from the deciding circuit 17 to convert the output signal to a smoothed signal and outputs it. Only the area judged to be moire components is given average processing like this. |
