Abstract: A color conversion system includes: an image reader that reads a test sheet on which a plurality of patches is formed and outputs a read image; and a hardware processor that analyzes a region of interest for each of the patches of the read image according to an operation mode for a color conversion table in which a read pixel value and a pixel value in a color space are associated with each other for each of the patches of the read image, and performs image noise removal processing, and performs color conversion of converting the read pixel value corresponding to the region of interest of the patch into a pixel value in the color space using the color conversion table in a case where the operation mode is a use mode.

Abstract: An image inspection apparatus includes: a reader that reads an image formed on a recording medium; a first processor that: inspects a first read image including one of divided images obtained by dividing the image at a predetermined position in a main scanning direction, and generates first inspection image data based on an inspection result of the first read image; and a second processor that: inspects a second read image including another of the divided images obtained by dividing the image, and generates second inspection image data based on an inspection result of the second read image.

Abstract: A stand-alone inspection apparatus inspects documents printed on a cut sheet, and includes: a sheet feeder capable of setting the documents in a sorted state; a sorting detector that detects the sorted state of the documents; an image reader that reads an image of the documents; an inspection part that inspects the documents on the basis of the read image; and a sheet ejector that ejects the inspected documents, wherein in a case where the documents in the sorted state are set in the sheet feeder, the sheet ejector ejects the documents in a state equivalent to the sorted state detected by the sorting detector.

Abstract: An image inspection apparatus includes a hardware processor that performs an image diagnosis on the basis of a read image obtained by reading images printed in both sides of a recording medium, wherein the hardware processor: acquires a read image obtained by reading an image on the recording medium to which at least a first chart and a second chart are output; and performs a diagnosis by determining a side to be used in the diagnosis depending on an image diagnosis item on the basis of the read image.

Abstract: A stand-alone inspection apparatus inspects documents printed on a cut sheet, and includes: a sheet feeder capable of setting the documents in a sorted state; a sorting detector that detects the sorted state of the documents; an image reader that reads an image of the documents; an inspection part that inspects the documents on the basis of the read image; and a sheet ejector that ejects the inspected documents, wherein in a case where the documents in the sorted state are set in the sheet feeder, the sheet ejector ejects the documents in a state equivalent to the sorted state detected by the sorting detector.

Abstract: Provided are image forming apparatuses, non-transitory recording media each storing a computer-readable program for obtaining paper information, and paper-information obtaining methods. An image forming apparatus includes at least one reflection-type optical sensor that measures a sheet in a sheet path, and at least one backing configured to change optical density of a backing face which is to be placed under a sheet in the sheet path for a measurement of the sheet with each of the at least one reflection-type optical sensor. A hardware processor in a system including the image forming apparatus, causes the at least one reflection-type optical sensor to take measurements of a sheet in the sheet path by using different optical densities of the backing face, and calculates paper weight, which is weight of paper per unit area, of the sheet on the basis of the result of the measurements.

Abstract: An image inspection apparatus includes a hardware processor that performs an image diagnosis on the basis of a read image obtained by reading images printed in both sides of a recording medium, wherein the hardware processor: acquires a read image obtained by reading an image on the recording medium to which at least a first chart and a second chart are output; and performs a diagnosis by determining a side to be used in the diagnosis depending on an image diagnosis item on the basis of the read image.

Abstract: Provided are image forming apparatuses, non-transitory recording media each storing a computer-readable program for obtaining paper information, and paper-information obtaining methods. An image forming apparatus includes at least one reflection-type optical sensor that measures a sheet in a sheet path, and at least one backing configured to change optical density of a backing face which is to be placed under a sheet in the sheet path for a measurement of the sheet with each of the at least one reflection-type optical sensor. A hardware processor in a system including the image forming apparatus, causes the at least one reflection-type optical sensor to take measurements of a sheet in the sheet path by using different optical densities of the backing face, and calculates paper weight, which is weight of paper per unit area, of the sheet on the basis of the result of the measurements.

Abstract: An image forming apparatus includes an image generating unit for generating a job image, a color verification image generating unit, a color converting unit for performing the same color conversion on the job image and the color verification image, a printing unit for printing the job image and the color verification image subjected to the color conversion, a colorimetry device for measuring the colors of a printout of the color verification image, a storage unit, a storing control unit for storing the job image in the storage unit in association with the color verification image and colorimetrical values thereof, and a reprinting control unit, wherein the printing unit performs a test print of the stored color verification image before reprinting, and the reprinting control unit compares colorimetrical values obtained during the test print with stored past colorimetrical values and outputs color differences.

Abstract: An image forming apparatus includes an image forming device, a gradation adjustment mark adder and a hardware processor. The hardware processor monitors and adjusts a gradation characteristic based on a result of scanning a gradation adjustment mark. The hardware processor makes a determination as to whether to form the gradation adjustment mark overlapping an image area of an image based on image data. If it is determined to form the gradation adjustment mark overlapping the image area, the hardware processor controls the gradation adjustment mark adder to add gradation adjustment mark information to the image data in the image area.

Abstract: An alignment sheet for alignment of an image forming position of a sheet includes a first side and a second side. The first side has a reference image which is formed in a periphery of the first side and which is used for measuring a position of an image on the first side. The second side has a background image with a predetermined area which is formed at a location where the background image does not overlap the reference image. The reference image and the background image are read at the same time by an image reading section while an area with the reference image is folded such that the background image appears as a background.

Abstract: An image forming apparatus includes: an image forming section; an image reading sensor and a colorimeter; a temperature sensor; a memory that stores a first color value and a second color value in a first color chart that has a larger number of patches than a second color chart; a processor that creates a scanner profile for converting a first color value into a second color value using color values obtained by the image reading sensor and the colorimeter, corrects the scanner profile according to the color values obtained by the image reading sensor and the colorimeter, and converts the first color value into the second color value using the corrected scanner profile.

Abstract: An image forming apparatus includes an image generating unit for generating a job image, a color verification image generating unit, a color converting unit for performing the same color conversion on the job image and the color verification image, a printing unit for printing the job image and the color verification image subjected to the color conversion, a colorimetry device for measuring the colors of a printout of the color verification image, a storage unit, a storing control unit for storing the job image in the storage unit in association with the color verification image and colorimetrical values thereof, and a reprinting control unit, wherein the printing unit performs a test print of the stored color verification image before reprinting, and the reprinting control unit compares colorimetrical values obtained during the test print with stored past colorimetrical values and outputs color differences.

Abstract: An image forming device includes an image forming unit, a conveying unit, a first image detecting unit, a second image detecting unit, and a controller, wherein the controller includes a detecting unit correcting mode in which the first image detecting unit is corrected by using an image detection result by the second image detecting unit, and in the detecting unit correcting mode, a transfer paper conveying speed at the time of image reading by the second image detecting unit is changed to the transfer paper conveying speed different from a normal transfer paper conveying speed at the time of image formation and the first image detecting unit is corrected based on read results of the same image by the first and second image detecting units.

Abstract: An image forming apparatus includes: an image forming section; an image reading sensor and a colorimeter; a temperature sensor; a memory that stores a first color value and a second color value in a first color chart that has a larger number of patches than a second color chart; a processor that creates a scanner profile for converting a first color value into a second color value using color values obtained by the image reading sensor and the colorimeter, corrects the scanner profile according to the color values obtained by the image reading sensor and the colorimeter, and converts the first color value into the second color value using the corrected scanner profile.

Abstract: An image forming apparatus includes an image forming device, a gradation adjustment mark adder and a hardware processor. The hardware processor monitors and adjusts a gradation characteristic based on a result of scanning a gradation adjustment mark. The hardware processor makes a determination as to whether to form the gradation adjustment mark overlapping an image area of an image based on image data. If it is determined to form the gradation adjustment mark overlapping the image area, the hardware processor controls the gradation adjustment mark adder to add gradation adjustment mark information to the image data in the image area.

Abstract: An image forming apparatus includes a control unit and first and second image scanning devices. The first and second image scanning devices scan the same surface of the same sheet with an image formed thereon on a sheet-conveying pathway. The image forming apparatus adjusts an image forming condition based on information acquired through the scan by the first and second image scanning devices. The first image scanning device scans only a part of an area in the main scanning direction. The second image scanning device scans an area across the image forming width in the main scanning direction. The control unit detects an anomalous value based on the information acquired through the scan by the second image scanning device, and prompts cleaning of the first and second image scanning devices in response to detection of the anomalous value.

Abstract: An image reading apparatus including: two image reading devices which are different from each other, read out a same surface of a same sheet after image formation on a sheet conveyance path and read out a plurality of common color patches formed in the same surface of the same sheet, one of the image reading devices being a first image reading device which reads out only a partial region in a main scanning direction and the other of the image reading devices being a second image reading device which reads out over an image formation width in the main scanning direction; and a calculation section which estimates a value equivalent to reading information of the first image reading device from reading information of the second image reading device on the basis of reading information obtained by reading out the common color patches.

Abstract: An image forming device includes an image forming unit, a conveying unit, a first image detecting unit, a second image detecting unit, and a controller, wherein the controller includes a detecting unit correcting mode in which the first image detecting unit is corrected by using an image detection result by the second image detecting unit, and in the detecting unit correcting mode, a transfer paper conveying speed at the time of image reading by the second image detecting unit is changed to the transfer paper conveying speed different from a normal transfer paper conveying speed at the time of image formation and the first image detecting unit is corrected based on read results of the same image by the first and second image detecting units.

Abstract: An alignment sheet for alignment of an image forming position of a sheet includes a first side and a second side. The first side has a reference image which is formed in a periphery of the first side and which is used for measuring a position of an image on the first side. The second side has a background image with a predetermined area which is formed at a location where the background image does not overlap the reference image. The reference image and the background image are read at the same time by an image reading section while an area with the reference image is folded such that the background image appears as a background.