Image forming apparatus and control method thereof

摘要

When a recording agent amount limiting process is carried out, a color reproduction range is narrowed, and therefore gradation properties of dark areas are deteriorated and information originally held by an image is sometimes undesirably lost. By obtaining (401) a colorant amount for each target pixel of input color image data, calculating (402) a colorant amount of a peripheral area of the target pixel, and correcting (400) a density range of the input color image data based on the colorant amount of the target pixel and the colorant amount of the peripheral area of the target pixel, amounts of recording agent are limited and reductions in image quality are prevented.

主权项

1. An image forming apparatus, comprising:
an obtainment unit configured to obtain a colorant amount for a target pixel in input color image data, wherein the colorant amount for the target pixel in the input color image data is the sum of respective color component values for the target pixel in the input color image data; a unit configured to apply filtering processing to the input color image data and to obtain a colorant amount for the target pixel in image data which has undergone the filtering processing; a correction unit configured to correct the colorant amount for the target pixel in the input color image data based on the colorant amount for the target pixel which has undergone the filtering processing; and a combination unit configured to combine the colorant amount for the target pixel in the input color image data and the corrected colorant amount for the target pixel corrected by the correction unit based on a combination ratio determined in accordance with the colorant amount for the target pixel in the image data which has undergone the filtering processing, wherein the correction unit corrects the colorant amount for the target pixel in the input color image data so that the colorant amount for the target pixel in the input color image data becomes smaller as the colorant amount for the target pixel which has undergone the filtering processing become larger, and wherein the combination unit determines the combination ratio so that a ratio of the corrected colorant amount for the target pixel becomes larger as the colorant amount for the target pixel which has undergone the filtering processing becomes larger.