US Patent 7865033 Method and apparatus for controlling contrast

A method and apparatus for contrast control is provided. The apparatus includes a cumulative density function which provides a second cumulative density function modified from a first cumulative density function based on a first luminance histogram of an input image; a transformer function provider which provides a transform function based on the first cumulative density function and the second cumulative density function; a compensation unit which compensates the transform function based on a predetermined illumination level; and a transform unit which transforms a luminance distribution of the input image based on the compensated transform function.