An image reading apparatus includes: a document size detector that detects either a length or a width of a fed document before reading, and associates the document with a standard size equal to or approximate thereto; an image reading device that reads a document and surroundings thereof at a reading position; a background color plate to be read as an image of the surroundings; a document area determiner that determines a document area; and a blank page determiner that determines a blank page determination area for determining whether a document is a blank page or not. When either of the detected length or width is equal to or more than a predetermined threshold value, the blank page determiner determines the blank page determination area, based on the associated standard size, and otherwise determines the blank page determination area, based on the document area.

A reading portion generates an original image including an image of a document sheet. A first document sheet end detection portion, in a case where the thickness of the document sheet is equal to or greater than a threshold value, identifies a peripheral edge shape of the document sheet by detecting a shadow portion that occurs at a peripheral edge portion of the document sheet in the original image. A second document end detection portion, in a case where the thickness of the document sheet is less than a threshold value, identifies the peripheral edge shape based on a specification by the user. A document sheet size determination portion determines a size of the document sheet according to a result of shape identification by the first document sheet end detection portion or a result of shape identification by the second document sheet end detection portion.

To provide a sheet conveyance device capable of preventing degradation in quality of conveying a sheet and image quality even when a stiffness of the sheet is different between a sheet conveyance direction and a sheet width direction. A sheet conveyance device of an image forming apparatus includes an image forming part that conveys a sheet along a conveyance path; and a stiffness acquisition part that acquires a stiffness of the sheet in a first direction including a component in the sheet conveyance direction by bending the sheet in the first direction, and acquires a stiffness of the sheet in a second direction including a component in the sheet width direction orthogonal to the sheet conveyance direction by bending the sheet in the second direction.

An information processing apparatus includes: a processor is configured to: read an image of at least one of a first surface or a second surface of a medium with the medium folded; discriminate whether the image is of the first surface or the second surface based on an identification image in the image; specify, based on the image, a surface on which a folding deviation occurs; and determine a correction direction of the folding deviation according to whether the surface on which the folding deviation occurs is the first surface or the second surface.

A reading device, an image forming apparatus, and a method of correction. The reading device includes a scanner configured to read an image in a first wavelength range and an image in a second wavelength range from light reflected by a surface of a recording medium, a detector configured to detect a change from a reference position in a reading-depth direction when the surface of the recording medium is read by the scanner, based on an amount of characteristic read from the image in the second wavelength range, and a corrector configured to correct the image in the first wavelength range based on the change detected by the detector. The image forming apparatus includes the reading device, and an image forming device configured to form an image corrected by the corrector of the reading device on a recording medium. The method includes reading the image in the first wavelength.

An information processing apparatus includes a sensor that detects a property of a specific sheet, and a processor configured to output information about a sheet that satisfies a set condition regarding a relationship with the property detected by the sensor. The sensor includes at least an infrared sensor that detects the property by emitting an infrared ray to a sheet or an electric sensor that detects the property on the basis of an electrical resistance.

An image forming system includes: an image forming apparatus; and a recording material information detecting apparatus provided outside the image forming apparatus, wherein the recording material information detecting apparatus includes a recording material information detector that detects recording material information about a recording material, and the image forming apparatus includes: an image former; an operation detector; and a hardware processor.

An image reading apparatus includes: a conveyance unit configured to convey the original; an image reading unit configured to read an image of the original conveyed by the conveyance unit by using a reading sensor to generate image data which represents a reading result; at least one processor configured to: detect a streak image in an image represented by the image data based on the image data; determine a content area in the image represented by the image data, the content area being an area where content is printed, and perform correction processing for removing the streak image by correcting the image data; wherein the at least one processor is configured to be operable in a first reading mode in which the correction processing is performed to image data corresponding to the streak image in an area outside the content area.

An image inspector includes a recording device and circuitry. The reading device is configured to read an image on a recording medium. The circuitry is configured to determine whether the recording medium has a wrinkle and an edge folding based on a plurality of positions on the image on the recording medium read by the reading device satisfying a predetermined relation. The circuitry is configured to determine whether the recording medium has the wrinkle based on the predetermined relation, and then determine whether the recording medium has the edge folding based on the predetermined relation.

A reading device includes: a reader; and a controller. The reader is configured to read both of a sheet of paper and a card as an original. The controller is, when the card having four original corners is set as the original, configured to perform for implementing a card reading function: (a) reading; and (b) acquiring. The (a) reading reads the original with the reader to acquire original image data corresponding to an original image area having four corner regions. The (b) acquiring acquires edge information of a first original corner from the original image data to estimate a round shape of the first original corner using the edge information. The first original corner being one of the four original corners in the original.