A reading device includes a light source, an image sensor, a background board, and an image processing circuitry. The light source irradiates visible light and invisible light to a subject. The image sensor receives the visible light and the invisible light, each of which is reflected from the subject, to capture a visible image and an invisible image. The background board is provided in an image capturing range of the image sensor. The background board is a background portion. The image processing circuitry detects a feature amount of the subject and the background portion from at least one of the visible image and the invisible image.

An image forming apparatus includes processing circuitry and an image forming device. The processing circuitry is configured to acquire characteristic information of a recording medium measured, and apply a preset calculation criterion to the characteristic information to calculate an image forming condition. The image forming device is configured to form an image on the recording medium based on the image forming condition calculated by the processing circuitry.

Before reading of a document, an image processing control portion makes an image reading portion perform pre-scanning operation, which is scanning operation performed with a document cover open without a document placed on a placement surface, and checks the incident condition of external disturbance light on the image sensor. If it is judged that the incident condition is a predetermined state, the image processing control portion makes a control device perform a countermeasure process to make the room dimmer than it currently is.

A surface object comprises a surface with a boundary, the surface having a background color. At least one optical marker is provided on the surface for assisting of image processing for improving appearance of an image of the surface with the boundary. At least one optical marker includes at least one color which is lighter or darker than the background color and the color different ΔE between the background color and the at least one color of the optical marker being between ΔE=2 and ΔE=18.

An image processing apparatus including: a first housing; and a second housing, the second housing including: a base part; a supporting part; an image reader; and a detector, the first housing including: an image forming unit and a cover, wherein: the cover has a 1st region disposed on a lower position of the detector and a 2nd region disposed on an upper position of a moving range of a recording head; the 1st region has a recessed part recessed downward, an inner bottom surface of the recessed part being disposed at a position lower that an upper edge position of the 2nd region; the base part has a housing part; and a lower edge of the detector is lower than the upper edge position of the 2nd region.

An optical scanning device includes a reflected-light passing unit having a passing region through which a portion of reflected light that is the scanning light reflected by the medium passes. An outer peripheral contour line of the passing region includes a contour curve configured with a set of points where coordinates in a direction orthogonal to a scanning direction are uniquely determined for the coordinates in the scanning direction. The contour curve renders a curve protruded toward the passing region. When a region in contact with the contour curve in the passing region is divided into a plurality of quadrilateral minute regions having equivalent areas and extending from the contour curve to a predetermined coordinate position in the scanning direction and are continuously arranged in the orthogonal direction, widths of the minute regions in the scanning direction are different for each location in the orthogonal direction.

A sheet detecting apparatus includes: a light emitting unit that emits light emitted toward a detection position; a light receiving unit that is provided to receive the light reflected by a sheet present at the detection position and that outputs an electric signal which corresponds to a received light amount; and an adjustment processing unit that adjusts, within a specified range, a duty ratio of a drive pulse signal used to drive the light emitting unit, so that a detection value of the electric signal output from the light receiving unit is included in a specified standard range; and a decision processing unit that decides the specified range based on a change range which is among a variable range of the duty ratio of the drive pulse signal and in which the detection value of the electric signal changes in response to a change in the duty ratio.

A first zone and a second zone of a scan surface may be scanned by an image sensor. A lid may be coupled to the scan surface and have an open position and a closed position, the lid being to cover the first zone and the second zone when in the closed position. The position of a lid may be determined based on a comparison of a scan of the first zone and a scan of the second zone.

A document placement detecting device includes a document table, a plate, a plurality of invisible light sources, an imaging device, and circuitry. The document table transmits light. The plate is openable and closable relative to the document table, and covers the document table in a closed state of the plate. The plurality of invisible light sources irradiate a placement area with invisible light via the document table. The placement area is an area of the document table on which a document is placed. The imaging device receives reflected light from the document, and outputs read data. The circuitry detects the placement of the document with a change in a read value of the read data output from the imaging device based on the irradiation with the invisible light.

An image processing apparatus includes a processor configured to: acquire image information obtained by an image reading apparatus including an illumination unit having an uneven balance in an amount of light in a sub-scanning direction; and specify a position of a folding line in a sheet from the acquired image information. The acquiring by the processor includes acquiring first image information obtained by reading the sheet in a first state in which the folding line in the sheet is positioned in a direction intersecting the sub-scanning direction of the image reading apparatus, and second image information obtained by reading the sheet in a second state in which the sheet is directed to an opposite side to a side in the first state. The specifying by the processor includes specifying the position of the folding line in the sheet based on the first image information and the second image information.