A background image is acquired by imaging an opening plate as a background of an original document in a state where the original document is not arranged. Next, an original document including background image is acquired by imaging the same range as the background image in a state where the original document is arranged on an upper surface of the opening plate. Next, a difference image is generated by subtracting the background image from the original document including background image. In addition, an inverse difference image is generated by subtracting the original document including background image from the background image. A region of the original document is detected based on the difference image and the inverse difference image.

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 information processing apparatus performs processing for putting a width of a line in an output in a case where printing is performed by a first printing apparatus based on print data including a line close to a width of a line in an output in a case where printing is performed by a second printing apparatus based on the print data. A first acquisition unit is configured to acquire first information relating to an output in a case where printed matter including a plurality of line width detection images is printed by the second printing apparatus.

An image reading apparatus comprises a platen, a support, a reader, an open/close unit, a first obtainer, a mark, a positioning member, and a determiner. A position of the mark on a pressing surface of the cover, is provided at a position at which, in a case where a sheet of a maximum size among standard sizes that can entirely fit in a readable range of the reader is positioned with respect to the positioning member, at least a portion of the mark is not hidden by the sheet as viewed from the reader.

An image processing apparatus includes a size acquisition unit and a decision unit. The size acquisition unit acquires first size information indicating a first sheet size of a first sheet surface read by an image reading unit. The decision unit decides second image information indicating a second image size of a second image to be stored of a second sheet surface different from the first sheet surface based on first image information indicating a first image size of a first image to be stored based on the first size information.

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.

A placement detection system includes: a placement table; an imaging device that images an object placed on the placement table to generate an input image; and a control device. The control device generates a first binarized image for the input image based on a first threshold value and determines whether the object is placed in a predetermined placement orientation. The control device changes a threshold value for a target pixel to a second threshold value higher than the first threshold value when the object is determined to be placed in the predetermined placement orientation, the target pixel being sandwiched between pixels having pixel levels lower than or equal to the first threshold value and has a higher pixel level than the first threshold value in a first region, generates a second binarized image for the target pixel based on the second threshold value, and detects a shape of the object.

An image reading apparatus comprising: an original reading unit configured to read an image of each of multiple originals placed on an original table in batch by a batch-scan; a cropping unit configured to crop an image of each original from an entire image which is read by the batch-scan; an image output unit configured to output a cropped image of each original; and a control unit configured to control the original reading unit, the cropping unit, and the image output unit, wherein the control unit makes the original reading unit read the image by a batch-scan in which an image density of an edge of each original is supposed to be higher than an image density of a reading-area outside of the original, and an area to be cropped is determined on the basis of a difference in the image density between the edge and the reading-area outside of the original.

A placement detection system includes: a placement table; an imaging device that images an object placed on the placement table through the placement table to generate an input image; and a control device that receives the input image. The control device identifies a higher-level pixel having a pixel level higher than or equal to a predetermined pixel level in the input image, sets a threshold value of the higher-level pixel, and sets a threshold value of a target pixel other than the higher-level pixel to a lower value than the threshold value of the higher-level pixel in accordance with a distance between the higher-level pixel and the target pixel. The control device binarizes a pixel level of the target pixel in accordance with the threshold value of the target pixel to produce a binarized image and detects a shape of the object by using the binarized image.

A background image is acquired by imaging an opening plate as a background of an original document in a state where the original document is not arranged. Next, an original document including background image is acquired by imaging the same range as the background image in a state where the original document is arranged on an upper surface of the opening plate. Next, a difference image is generated by subtracting the background image from the original document including background image. In addition, an inverse difference image is generated by subtracting the original document including background image from the background image. A region of the original document is detected based on the difference image and the inverse difference image.