Method and apparatus for analyzing and correcting the gradation of an original

摘要

In a method of obtaining a color correcting condition for a color image on an image frame, plural color component image signals are obtained for each pixel of the color image of the frame, the frame is divided into plural blocks each of which is composed of plural pixels; a block color density value statistic is obtained for each block from the plural color component signals of the plural pixels of each block, wherein the statistic indicates a relationship between a density value and a number of pixels indicating the density value; a chroma level of each block is evaluated based on the block color density value statistic; a frame color density value statistic is obtained from the plural color component signals of the plural pixels of the plural blocks of the frame by reducing an influence of a block evaluated as a high chroma block; and the color correcting condition for the color image is determined based on the frame color density statistic. <IMAGE>