IMAGE PROCESSING APPARATUS AND METHOD

PROBLEM TO BE SOLVED: To provide an image processing apparatus capable of nonlinearly transforming luminance and saturation independently without changing any hue, and capable of improving the image quality when the nonlinear transformation of a relatively dark image is performed. SOLUTION: A transformation coefficient calculation unit 7 calculates a luminance transformation coefficient and a saturation transformation coefficient which should be used for nonlinear transformation processing of each targeted pixel which is a processing target pixel in an image signal. A signal level transforming unit 9 nonlinearly transforms a pixel signal of the targeted pixel on the basis of the luminance transformation coefficient and the saturation transformation coefficient. The signal level transforming unit 9 respectively changes the luminance and the saturation in accordance with the luminance transformation coefficient and the saturation transformation coefficient. Thereby, the luminance and the saturation are separately transformed without changing any hue. A value corresponding to the luminance transformation coefficient and smaller than the luminance transformation coefficient can be obtained as the saturation transformation coefficient. Accordingly, even when performing the nonlinear transformation processing for a dark image, saturation transformation as well as luminance transformation are performed. COPYRIGHT: (C)2011,JPO&INPIT