IMAGE PROCESSING APPARATUS AND IMAGE PROCESSING METHOD

摘要

By the gradation correction extending in the dynamic range in accordance wit h the maximum value and the minimum value of the video luminance signal, it ma y be impossible to produce a sufficient correction effect depending on the display image. To cope with this, a histogram detection circuit (2), a maxim um value detection circuit (3), and a minimum value detection circuit (4) respectively determine a maximum value (Kmax), a minimum value (Kmin), and information on distribution in the gradation direction for each field in detection window in the screen. The determined maximum value (Kmax) and minimum value (Kmin) are respectively corrected by a maximum value correctio n circuit (5) and a minimum value correction circuit (6) in accordance with th e output result of the histogram detection circuit (2), so that a corrected maximum value (Lmax) and a corrected minimum value (Lmin) are output. An inp ut video liminance signal is corrected in accordance with the corrected maximum value (Lmax) and the corrected minimum value (Lmin). Thus, it is possible to obtain a gradation correction effect optimal for a scene.