Patent ID: 7440639

Claim:
An image reading apparatus comprising: at least three line sensors having filters, respectively, different in spectral sensitivity, and arranged in a predetermined order in a subscanning direction with a distance therebetween to scan an original in the subscanning direction; a platen arranged between the original and said at least three line sensors; a mover moving said platen at a rate relative to said at least three line sensors, said rate being different from that of the original relative to said at least three line sensors; an interline corrector receiving at least three data from said at least three line sensors to synchronize said at least three data to be a pixel having read a single location on the original; and a noise pixel detector receiving said at least three data synchronized by said interline corrector, one line at a time, sequentially, said noise pixel detector including an extractor extracting a feature pixel from each of said at least three data, said feature pixel having a predetermined feature, a detector comparing said at least three data corresponding to a single location on the original to detect said feature pixel extracted from one of said at least three data, as a noise pixel if said feature pixel is not a feature pixel for each of said at least three data other than said one of said at least three data, a color determiner determining a color of each pixel from said at least three data, a determiner depending on a color of a pixel neighboring a pixel to be processed selected from pixels arranged in the main scanning direction, to determine among said at least three data first data from which a noise pixel is initially detected, and a noise pixel determiner invalidating a noise pixel detected by said detector identical in location in the main scanning direction to said pixel to be processed, that is included in a line input prior to a line including said noise pixel detected from said first data and that is detected from data other than said first data.