Patent ID: 8189113

Claim:
An image processing apparatus comprising: an input unit configured to input pixel signals of respective pixels which form an image; an acquisition unit configured to acquire histogram data by counting the numbers of pixels for respective levels of the pixel signals input by the input unit; a setting unit configured to set correction amounts for changes amounts of levels of the pixel signals based on the histogram data acquired by the acquisition unit; a first correction unit configured to correct a change amount of levels of pixel signals near a pixel to be processed based on the correction amounts set by the setting unit; and a second correction unit configured to correct the level of the pixel signal input by the input unit in association with the pixel to be processed using the change amount of the levels of the pixel signals corrected by the first correction unit, wherein the correction amounts hold a change amount less than a first reference value, correct a change amount not less than the first reference value and less than a second reference value to the first reference value, and correct a change amount not less than the second reference value and less than a third reference value to a change amount not more than the first reference value, and wherein the setting unit sets, as the correction amounts, data obtained by correcting the predetermined first and third reference values by values calculated based on the histogram data.