Image forming apparatus, image forming system, inspection method, and non-transitory recording medium

An image forming system comprising:

• a reading device;
• and
• a printer comprising circuitry configured to:
• cause a reading device to read a printed matter printed by a printing apparatus based on print data to generate a first image to be inspected;
• detect a defect on the printed matter based on a master image and the first image, the master image being generated from the print data of the printed matter;
• detect a defect on a second image to be inspected and a defect state of the defect, the second image being generated by the reading device without sheet passage;
• set a region including a position of the defect detected on the second image to an inspection exclusion region to be excluded from detection of a defect on the first image;
• and
• notify a user in a case that the defect state is determined to exceed a threshold value.

An inspection method comprising:

• with a reading device, reading a printed matter printed by a printing apparatus based on print data to generate a first image to be inspected;
• detecting a defect on the printed matter based on a master image and the first image, the master image being generated from the print data of the printed matter;
• detecting a defect on a second image to be inspected and a defect state of the defect, the second image being generated by the reading device without sheet passage;
• setting a region including a position of the defect detected on the second image to an inspection exclusion region to be excluded from detection of a defect on the first image;
• and
• notifying a user of an abnormality in a case that the defect state is determined to exceed a threshold value.