Image signal processing apparatus

摘要

An image signal processing apparatus has a color decorder for preparing a histogram for the brightness level of each color signal of an input image signal such as an NTSC signal, and an image process circuit for calculating a cumulative brightness distribution curve of the histogram and for performing gamma-correction of the input image signal in accordance with the cumulative brightness distribution curve. A CPU in the image process circuit can calculate upper and/or lower extremities of each cumulative distribution curve and perform normalization of each color signal within the range defined by the calculated upper and/or lower extremity.