Image forming apparatus and image correcting method

An image forming apparatus comprising:

• an inkjet head having a plurality of nozzles each ejecting a droplet;
• an image abnormality detecting device configured to detect abnormality of an image caused by abnormality of a nozzle of the plurality of nozzles from the image recorded on a recording medium by the inkjet head;
• and
• a correcting device configured to perform correction of lowering visibility of a missing portion by making a part of the plurality of nozzles non-ejectable and by compensating for the missing portion in the recorded image caused by the non-ejection by recording from another nozzle based on a detection result by the image abnormality detecting device, wherein:
• the correcting device includes:
• a plural non-ejection correcting device configured to perform correction by making two or more of the nozzles non-ejectable with respect to one abnormal nozzle;
• and
• a single non-ejection correcting device configured to perform correction by making one abnormal nozzle non-ejectable with respect to the one abnormal nozzle, and
• after a plural non-ejection correction is performed that carries out correction by making a nozzle group belonging to a nozzle range corresponding to a region including the abnormality detected by the image abnormality detecting device and including the abnormal nozzle non-ejectable by the plural non-ejection correcting device, a single non-ejection correction is performed which carries out correction by making the abnormal nozzle non-ejectable by the single non-ejection correcting device.