Patent ID: 8174622

Claim:
A data processing method of executing nonlinear conversion for image data which have a plurality of pixel data, comprising: a first step of obtaining a second amount of statistics corresponding to the number of pixel data having a gradation value in a second range included in a predetermined first range based on gradation values of the plurality of pixel data of the image data; a second step of obtaining a first amount of statistics corresponding to the number of pixel data having a gradation value in the first range; an adjusting step of adjusting the second amount of statistics obtained in said first step using a first gain which is determined based on the first amount of statistics obtained in said second step such that the greater the first amount of statistics is, the smaller the second amount of statistics is; a determining step of determining a conversion characteristic of the nonlinear conversion based on the second amount of statistics adjusted in said adjusting step; and a generating step of performing the nonlinear conversion to the image data using the conversion characteristic determined in said determining step to generate nonlinear-converted image data.