| 摘要 |
PROBLEM TO BE SOLVED: To remove noise images caused by dust from a read image, by detecting existence of dust at a reading position of a manuscript accurately. SOLUTION: In the dust detecting circuit 9, a change in density of line direction of two or more pixels which are in a row in each main scanning line, based on the density of each pixel contained in image data. From the density of pixel group (16-pixel group in front of the scanning direction and 4-pixel group in the rear of the scanning direction), which are located in a predetermined range from a pixel of interest on the line, each pixel having density deviating, not less than a threshold, onto the lower density side, and arranged in a row continuously in a number not less than a predetermined number (two pixels) in the main scanning line are extracted as abnormal pixels. From the dust detecting circuit 9, dust detection data for indicating the position of the extracted abnormal pixels on the main scanning line is generated to a noise removing circuit 10. COPYRIGHT: (C)2007,JPO&INPIT |
