초록 ▼

An image reading unit reads an original image, one main scan line by one main scan line, in a sub-scan direction. A window setting unit sets a measuring window in a bit-map formation of image data obtained through the image reading unit, in a manner in which the measuring window moves in a predeterm

An image reading unit reads an original image, one main scan line by one main scan line, in a sub-scan direction. A window setting unit sets a measuring window in a bit-map formation of image data obtained through the image reading unit, in a manner in which the measuring window moves in a predetermined manner so that the measuring window appropriately includes pixels of an oblique line image which is formed in the bit-map formation of image data as a result of being read through the image reading unit. A position error measuring unit processes image data defined by the measuring window, and, thus, measures an error of the oblique line image formed in the bit-map formation of obtained image data between a predetermined reference state and an actual reading state.

대표청구항 ▼

[ What is claimed is:] [1.] An image reading apparatus comprising:image reading means for reading an original image, one main scan line by one main scan line, in a sub-scan direction;window setting means for setting a measuring window in a bit-map formation of image data obtained through said image

[ What is claimed is:] [1.] An image reading apparatus comprising:image reading means for reading an original image, one main scan line by one main scan line, in a sub-scan direction;window setting means for setting a measuring window in a bit-map formation of image data obtained through said image reading means, in a manner in which said measuring window moves along an oblique line image which is formed in said bit-map formation of image data as a result of being read through said image reading means; andcenter of gravity calculating means for calculating the center of gravity of image data of pixels defined by said measuring window in said bit-map formation of said image data;window shifting control means for determining whether or not said measuring window is shifted according to a center of gravity calculation result of said center gravity calculating means; andposition error measuring means for measuring a reading pixel position error from said center of gravity calculated by said center of gravity calculating means.