Provided herein is an image processing apparatus comprising: input means for inputting image data, which is obtained by digitalizing an image signal that has been converted from light from an object to an electric signal by an image sensor, and performing no compression or lossless compression; image processing parameter input means for inputting a parameter to be employed in image processing on the image data executed by a user; image processing means for performing luminance-related processing or chrominance-related processing on the image data in accordance with the image processing parameter inputted by the image processing parameter input means; and storage means for storing an intermediate result for each of the luminance-related processing and the chrominance-related processing. By virtue of storing the intermediate results, this invention contributes not only to high-speed RAW image data development processing, but also to a reduced image processing load and increased processing speed.