An image reading apparatus includes an imaging device for generating a white reference image of a white reference member and a document image of a document and a periphery of the document, and a processor for performing first processing for detecting a dirt substance from the white reference image, generating data for shading correction based on the white reference image, correcting the document image using the data for shading correction to generate a correction image, and performing second processing for detecting a dirt substance from the correction image. One of the first processing or the second processing is performed using a dirt substance detection result of the other one of the first processing or the second processing.

A multifunction peripheral includes a conveyance roller, a print engine, a scanner, and a controller. The controller is configured to perform: driving the conveyance roller to convey a recording medium and controlling the print engine to record, on the recording medium, a test image based on test image data with recording agent; after recording the test image, controlling the scanner to generate scan data of the test image recorded on the recording medium; after generating the scan data, extracting, based on the scan data and the test image data, stain data indicative of a stain caused by transfer of the recording agent from the conveyance roller to the recording medium; after extracting the stain data, generating correction data by removing the stain data from the scan data; and executing particular processing by using the correction data.

Embodiments relate to a pixel defect detection circuit for detecting and correcting defective pixels in captured image frames. The pixel defect detection circuit includes a defect pixel location table that maps pixel locations in an image frame to respective confidence values, each confidence value indicating a likelihood that a corresponding pixel is defective. The pixel defect detection circuit further includes a dynamic defect processing circuit configured to determine whether a first pixel of an image frame is defective, and a flatness detection circuit configured to determine whether the first pixel is in a flat region of the image frame. The confidence value corresponding to the location of the first pixel is updated based upon whether the first pixel is determined be defective if the first pixel is determined to be in a flat region, and not updated if the first pixel is determined to not be in a flat region.

A reading device includes a main body section, a cover configured to be opened and closed with respect to the main body section, a transport path constructed by the main body section and the cover, a roller that transports an original document, a glass plate arranged on the transport path, and a reading section that performs reading by receiving light through the glass plate, a display section, and a control section, and the control section causes the display section to display a device image in which a stain corresponding region corresponding to a position of the stain on the glass plate is specified in a glass plate image region expressing the glass plate, the device image being an image depicting the reading device in a state where the cover is opened and a configuration including a part of the transport path, the roller, and the glass plate is exposed.

An image processing apparatus includes circuitry to: obtain a read image read from an image of a document output from an image reading device; detect an edge between a background area and a document area in the read image; sample a detection result of the edge at each first interval in a first direction to extract a first boundary point group including a plurality of boundary points; sample the detection result of the edge at each second interval in the first direction to extract a second boundary point group including a plurality of boundary points; determine a noise removal condition based on the first boundary point group; remove, from the second boundary point group, a boundary point satisfying the noise removal condition as noise; and calculate a linear equation approximating the second boundary point group from which the noise is removed.

An image forming apparatus disclosed herein includes a scanner configured to read a document to generate an image signal and a processor configured to determine a correction position. The correction position is determined in a main scanning direction based on primary data serving as an average value of pixel values in a sub scanning direction of the image signal. The processor may set a correction parameter based on the determined correction position. The image forming apparatus further includes an image processing circuit configured to correct the image signal based on the correction parameter and an image forming circuit configured to generate image data based on the image signal corrected by the image processing circuit.

In accordance with an embodiment, in an image processing apparatus which includes an arithmetic element and executes an image processing on a first image data read by a scanner from a manuscript including a printing area, the arithmetic element acquires the first image data from the scanner, generates second image data by executing an image processing on the first image data, recognizes the printing area in the first image data based on the second image data, and cuts out an image in the printing area from the first image data as a third image data.

An image processing device includes a light source, an image reader, and circuitry. The light source is configured to irradiate an object at least with invisible light. The image reader is configured to read first information and second information. The first information is included in the object and indicating a first characteristic in response to the object being irradiated with the invisible light. The second information is included in the object and indicating a second characteristic in response to the object being irradiated with the invisible light. The circuitry is configured to selectively output the first information read by the image reader.

A reading device is configured to detect an edge position of a target object to be conveyed in a conveyance direction. The edge position is a position of an edge of the object in a width direction intersecting the conveyance direction. The reading device includes a sensor device, an adder, and an edge position detector. The sensor device includes a pixel array including a plurality of elements arranged in the width direction. The adder is configured to add detection signals output from the elements at respective positions in the width direction. The edge position detector is configured to detect the edge position on basis of a position at which an output of the adder changes to a value larger than a threshold. Each element is configured to output a detection signal based on a reception amount of light in one of different wavelength bands.

An image processing apparatus includes circuitry to: obtain a read image read from an image of a document output from an image reading device; detect an edge between a background area and a document area in the read image; sample a detection result of the edge at each first interval in a first direction to extract a first boundary point group including a plurality of boundary points; sample the detection result of the edge at each second interval in the first direction to extract a second boundary point group including a plurality of boundary points; determine a noise removal condition based on the first boundary point group; remove, from the second boundary point group, a boundary point satisfying the noise removal condition as noise; and calculate a linear equation approximating the second boundary point group from which the noise is removed.