Image forming apparatus, control method of image forming apparatus, and storage medium

A control method of an image forming apparatus, the control method comprising:

• performing print processing while conveying a sheet based on image data;
• generating correction information for correcting a sensed value of a scan unit based on scanned data obtained by the scan unit reading a first chart output in the print processing and colorimetric data obtained by a colorimetry unit measuring the first chart;
• generating color adjustment information in accordance with characteristics of a printing unit of the image forming apparatus by correcting the sensed value of the scan unit by using the correction information based on colorimetric data obtained by the colorimetry unit measuring a second chart output in the print processing;
• and
• performing color adjustment processing for the image data by using the color adjustment information, wherein
• the first chart includes a patch extending in a main scanning direction substantially perpendicular to a sheet conveyance direction and having a uniform density, and a position adjustment pattern formed outside the patch for identifying a position in the main scanning direction on the patch and
• the correction information is generated by causing a pixel position of an end portion of the patch in the scanned data and a colorimetry position of an end portion of the patch in the colorimetric data to correspond to each other and determining a corrected value of the sensed value at a specific pixel position.

A non-transitory computer readable storage medium storing a program for causing a computer to perform a control method of an image forming apparatus, the control method comprising:

• performing print processing while conveying a sheet based on image data;
• generating correction information for correcting a sensed value of a scan unit based on scanned data obtained by the scan unit reading a first chart output in the print processing and colorimetric data obtained by a colorimetry unit measuring the first chart;
• generating color adjustment information in accordance with characteristics of a printing unit of the image forming apparatus by correcting the sensed value of the scan unit by using the correction information based on colorimetric data obtained by the colorimetry unit measuring a second chart output in the print processing;
• and
• performing color adjustment processing for the image data by using the color adjustment information, wherein
• the first chart includes a patch extending in a main scanning direction substantially perpendicular to a sheet conveyance direction and having a uniform density, and a position adjustment pattern formed outside the patch for identifying a position in the main scanning direction on the patch and
• the correction information is generated by causing a pixel position of an end portion of the patch in the scanned data and a colorimetry position of an end portion of the patch in the colorimetric data to correspond to each other and determining a corrected value of the sensed value at a specific pixel position.