A printer includes: an imaging device that has an opening window to which light from a medium is incident; a supply unit, a transport unit, and a carriage moving unit which cause the imaging device and the medium to relatively move. The printer causes the imaging device to image a correcting pattern which is used to correct density irregularity such that imaging data is acquired, and corrects the density irregularity, based on the imaging data.

The present disclosure relates to systems and computer-implemented methods for obtaining both high-resolution red-green-blue (RGB) data and other data of an image-bearing surface using a single sensor array. The technique includes obtaining, using a sensor array configured to obtain measurements of M4 different spectral sensitivity responses per output pixel at low resolution, spectrophotometric data representing a plurality of output pixels representing the image-bearing surface, determining, using at least one electronic processor and based on the spectrophotometric data, high-resolution RGB data representing the image-bearing surface, determining, using at least one electronic processor and based on the spectrophotometric data, additional data representing a plurality of output pixels representing the image-bearing surface, and outputting the high-resolution RGB data and the additional data.

A correction method for an image forming apparatus including a light source, a photosensitive member configured to rotate in a first direction, and a deflecting unit configured to deflect light beams emitted from the light source in a second direction orthogonal to the first direction to form scanning lines, the correction method including: a first correction step of correcting sparseness and denseness of density by moving a predetermined pixel in the first direction to output a pixel value of the predetermined pixel; and a second correction step of correcting the pixel value of the predetermined pixel by, when the pixel value of the predetermined pixel moved in the second direction is equal to or less than a predetermined value, adding the pixel value to a pixel value of a subsequent pixel of the predetermined pixel in the second direction without outputting the pixel value of the predetermined pixel.

An image scanning apparatus has a conveyer, a first scanning device configured to scan an image on one surface of an original sheet at a first scanning position, a second scanning device configured to scan an image on an other surface of the original sheet at a second scanning position. A controller is configured to execute a first adjustment process to adjust light amount adjustment of the first scanning device before scanning the original sheet subject to the received scanning instruction, start scanning after the first adjustment process, execute a determination process to determine, after starting conveying the original sheet, whether a light adjustment of the second scanning device is to be executed, execute a second adjustment process, when it is determined to start the light adjustment of the second scanning device, and stop conveying the original sheet when no original sheet is located at the first scanning position.