METHOD FOR DETECTING POSITION DEVIATION ORDER, METHOD FOR CORRECTING POSITION DEVIATION OF IMAGE, METHOD FOR CREATING STREAK UNEVENNESS CORRECTION TABLE, AND METHOD FOR CORRECTING STREAK UNEVENNESS

摘要

In an inkjet printer in which a plurality of heads in each of which a plurality of ink discharge nozzles are arranged in a main scanning direction are arranged in the main scanning direction in order to correct image position deviation more precisely, the selection of a correction test pattern for each scale of the magnitude of position deviation of a printed image is implemented. A difference between input image data of an arbitrarily defined image and output image data acquired by scanning the image, which has been printed, by a scanner is calculated pixel by pixel. A minimum pixel group composed of a plurality of pixels in which the calculated difference exceeds a predetermined threshold value is specified. According to the situations of the pixels within the specified minimum pixel group, the degree of the magnitude of the position deviation is determined to be any of a pixel size order, a head size order, and an image size order, or a combination thereof, and thereafter position deviation correction processing is performed using a correction chart created in advance according to the determined scale of the magnitude of the position deviation.