Apparatus, method and program for reducing deterioration of processing performance when graduation correction processing and noise reduction processing are performed

摘要

An image signal processing apparatus includes the following elements. A control unit determines a gradation correction characteristic representing a conversion characteristic for correcting brightness of an input frame. A separation unit separates the determined gradation correction characteristic into a representative gradation correction value representing an amount of correction for a representative value of a main subject and a remaining gradation correction characteristic obtained by removing the representative gradation correction value from the gradation correction characteristic. A gain processing unit uniformly applies the separated representative gradation correction value to the frame as a gain. A noise reduction processing unit performs noise reduction processing on the frame to which the representative gradation correction value is applied. A gradation correction processing unit performs gradation correction processing on the frame for which the noise reduction processing has been performed using the separated remaining gradation correction characteristic.