An image forming apparatus including a plurality of sheet feeding cassettes includes a control unit. The control unit performs control. In a case where a predetermined condition is satisfied during execution of a print job to print image data, the control unit performs control to execute interruption processing of a correction job to print a correction patch. The control unit performs control to determine, from the plurality of sheet feeding cassettes, a sheet feeding cassette to be used for the correction job based on information on the sheet feeding cassette used for the print job.

A determination is made on whether or not a recording medium is held in a state where calibration is executable, and the execution is pending in a case where the recording medium is not held. When the execution is pending, the determination is made again after a predetermined period elapses, and the calibration is executed in a case where the recording medium is held.

An image processing apparatus includes an acquisition unit configured to acquire first image data indicating a reference image as a target print result, and second image data indicating a target image to be inspected, and a processing unit configured to inspect the target image by performing a correction on a second partial region adjacent to a first partial region to enhance the second partial region relative to a difference image representing a difference between the reference image and the target image based on the first image data and the second image data, the first partial region having a difference in between the reference image and the target image.

An image processing apparatus comprises: an image forming unit configured to form an image on a recording medium using a plurality of color materials on the basis of first image data showing an image; and an estimating unit configured to estimate a characteristic of each one of the plurality of color materials in a target region on the formed image on the basis of second image data obtained by reading the formed image. The estimating unit selects an estimation processing unit to use from among a plurality of estimation processing units used for different estimation methods on the basis of a combination of the color materials in the target region.

A method for printing at least a first and a later print job includes receiving a first print job containing first image data of one or more first images to be printed in a printable area and a later print job containing later image data associated with a colour, determining a first sub-area of said printable area where no image of the first images is to be printed, using the first image data; printing the one or more first images in the printable area and at least one first control patch in the first sub-area, using for said at least one first control patch at least one colour representative for the colour associated with the later image data, measuring the colour of the printed at least one first control patch, and using the measured colour of the at least one first control patch for controlling the later print job.

A determination is made on whether or not a recording medium is held in a state where calibration is executable, and the execution is pending in a case where the recording medium is not held. When the execution is pending, the determination is made again after a predetermined period elapses, and the calibration is executed in a case where the recording medium is held.

An image processing apparatus includes an acquisition unit configured to acquire a reference image serving as a reference printing result and a target image serving as a printing result to be inspected, a correction unit configured to correct the target image based on a paper white area of each of the reference image and the target image so that a paper white color of the paper white area of the target image matches a paper white color of the paper white area of the reference image, wherein the paper white area is determined based on a positional displacement between the reference image and the target image, and an inspection unit configured to inspect the printing result by comparing the corrected target image with the reference image.

An image forming apparatus comprises an image forming unit; a sensor that measures a measurement image; and a controller. The controller controls the image forming condition based on a measurement result of measuring a first measurement image; acquires information having a correlation to density variation of images to be formed by the image forming unit; controls the image forming condition based on the information; determines a first value regarding a density of an image to be formed, based on a measurement result of measuring a second measurement image; determines a second value regarding a density of the image to be formed by the image forming unit, based on the information; and controls a timing at which the image forming unit next forms the first measurement image, based on the first value and the second value.

An image processing apparatus comprises a generation unit configured to generate correction information for reducing density change in image formation using a printing material including a plurality of colors. The generation unit generates correction information, sequentially in ascending order from a region of a smaller number of printing materials in a read-out image acquired by reading an image formed using a printing material including a plurality of colors, the correction information corresponding to a printing material for which correction information has not been generated among the printing materials used for the region.

An image forming apparatus includes: an image forming unit configured to form a reference image, and a plurality of test images; a conveying unit configured to convey the sheet; a reading unit configured to read the sheet, and output read data, the reading unit including a plurality of light-receiving elements disposed along a direction orthogonal to a conveyance direction of the sheet; and a controller configured to: determine a direction in which the plurality of test images are disposed based on read data related to the reference image; determine test image read data related to test image regions corresponding to each of the plurality of test images from the read data based on the direction; and control a density of an image to be formed by the image forming unit based on the test image read data.