A fiducial on a backer of a flatbed scanner is used for determining a media size of a target scanned on the platen of the scanner. The fiducial is comprised of a plurality of symbols, either arranged in a predetermined pattern or randomly within a fiducial frame, and is placed at a predetermined location on the backer on the scanner lid. Each symbol has a finish that reflects light differently than a finish on the backer and has a high peak correlation value and a low off-peak correlation value when scanned. Image data from a scan of a target along with the backer is searched for the fiducial image. When the fiducial image is found, the media is selected to be of a first shorter length target type and, when the fiducial is not found, the target is selected to be of a second longer length target type.

According to one embodiment, there is provided an image processing apparatus including a reading unit and a determining unit. The reading unit generates sheet image data indicating image data of a sheet. The determining unit determines, on the basis of a degree of gradation in the sheet image data generated by the reading unit, whether a planar object adheres on the sheet read by the reading unit.

An image processing apparatus includes: an image processing unit configured to execute image processing including skew correction that deforms an image so as to cancel distortion on the image; and a control unit configured to control the image processing on the image processing unit, wherein, in a case where a margin amount available for correcting the distortion is defined as a first correction margin amount and a margin amount used for correction other than skew correction is defined as a second correction margin amount, the control unit calculates a third correction margin amount obtained by subtracting the second correction margin amount from the first correction margin amount, and controls such that the image processing unit executes the image processing including the skew correction toward a first image and a second image such that the skew correction amount to be corrected falls within a range of the third correction margin amount.

An image reading apparatus further includes a discrimination unit which discriminates double feeding of a document from a carrier sheet, based on a double feeding detecting sensor (double feeding detecting unit) which detects double feeding of a document, a first detection result (section of L1) which is obtained when the double feeding detecting sensor detects a bonding portion of the carrier sheet, and a second detection result (double feeding detection value which is lower than second threshold value) which is obtained when the double feeding detecting sensor detects double feeding.

To provide a sheet size determining apparatus capable of appropriately determining a sheet size. Specifically, a sheet size detection result is acquired by a sensor, and when there are a plurality of candidate sheet sizes corresponding to the acquired detection result, a sheet size is determined from the plurality of candidate sheet sizes in response to a setting of the operation device that indicates sheet sizes.

An image reading device includes a contact glass, a document transport device, a first reading module, a second reading module, a opposite roller, and roller holders. The opposite roller transports a document while keeping it in close contact with an image reading surface of the second reading module arranged inside the document transport device. The roller holders rotatably support the opposite roller, and on their faces facing the second reading module, a pair of patterns for detection is provided to detect the inclination of the opposite roller. The patterns for detection are each formed to be increasingly wide toward a first end side in the axial direction upstream from an intersection in a central part thereof in the document transport direction, and increasingly wide toward a second end side opposite from the first end side downward from the intersection in the document transport direction.

An image reading apparatus includes a gray reference member, a reading unit, an adjusting unit, a calibration unit, a storage unit, and a control unit. The control unit is configured to execute a first preprocessing and a second preprocessing. The first preprocessing includes: acquiring first black data from one line worth of image data; acquiring white data; calculating white-black difference data; acquiring first light gray data; and calculating first light gray-black difference data. The second processing includes: acquiring second black data from the one line worth of the image data; acquiring second light gray data; calculating second light gray-black difference data; calculating a change ratio by dividing the second light gray-black difference data by the first light gray-black difference data; and calculating calibration data by multiplying the white-black difference data by the change ratio. Shading of the image data is calibrated in response to the calibration data.

A scanner includes a platen having a surface supporting items for scanning, and a projector adjacent (e.g., above or below) the platen. The projector projects light displaying patterned alignment marks on the items located on the platen. The patterned alignment marks identify an alignment position for the items to be located on the platen for properly aligned scanning. The projector projects different patterned alignment marks based on different characteristics of different items to be scanned.

An image forming apparatus includes an image forming unit, a display, a reading unit configured to read a reference image formed on a test sheet by the image forming unit, wherein the reference image includes a mark corresponding to a reading order, a controller configured to control the image forming unit to form the reference image, cause the reading unit to execute a first reading operation, determine whether first read data is obtained, inform of a reading error if the first read data is not obtained in the first reading operation, cause the reading unit to execute a second reading operation, determine whether second read data is obtained, and inform of a reading error if the second read data is not obtained in the second reading operation, and an adjustment unit configured to adjust image forming positions based on the first read data and the second read data.

A fiducial on a backer of a flatbed scanner is used for determining a media size of a target scanned on the platen of the scanner. The fiducial is comprised of a plurality of symbols, either arranged in a predetermined pattern or randomly within a fiducial frame, and is placed at a predetermined location on the backer on the scanner lid. Each symbol has a finish that reflects light differently than a finish on the backer and has a high peak correlation value and a low off-peak correlation value when scanned. Image data from a scan of a target along with the backer is searched for the fiducial image. When the fiducial image is found, the media is selected to be of a first shorter length target type and, when the fiducial is not found, the target is selected to be of a second longer length target type.