Image processing apparatus and image processing method for performing tone correction of an output image

摘要

An image processing apparatus comprises a region discrimination unit configured to discriminate object regions included in an image; a first calculation unit configured to calculate representative luminance values of a plurality of object regions discriminated by the region discrimination unit; a second calculation unit configured to calculate luminance distribution information of each of the plurality of object regions discriminated by the region discrimination unit; a determination unit configured to determine tone characteristics based on the representative luminance values of the plurality of object regions calculated by the first calculation unit and the pieces of luminance distribution information of the plurality of object regions calculated by the second calculation unit; and an image processing unit configured to perform tone correction processing based on the tone characteristics determined by the determination unit.

主权项

1. An image processing apparatus comprising one or more processors that function as:
a region discrimination unit configured to discriminate object regions included in an image; a first calculation unit configured to calculate representative luminance values of a plurality of object regions discriminated by the region discrimination unit; a second calculation unit configured to calculate luminance histograms of the plurality of object regions discriminated by the region discrimination unit; a determination unit configured to determine tone characteristics based on the representative luminance values of the plurality of object regions calculated by the first calculation unit and the luminance histograms of the plurality of object regions calculated by the second calculation unit; and an image processing unit configured to perform tone correction processing based on the tone characteristics determined by the determination unit, wherein the determination unit calculates a plurality of input/output characteristics based on the respective representative luminance values of the plurality of object regions, and calculates input value ranges respectively using the plurality of input/output characteristics based on the respective luminance histograms of the plurality of object regions, and determines the tone characteristics by combining the plurality of calculated input/output characteristics, wherein the determination unit calculates the input value ranges respectively using the plurality of input/output characteristics based on a luminance value obtained when values added to a luminance histogram of a first object luminance side reach a predetermined threshold, and determines the tone characteristics.