An image processing apparatus which provides image data to an image forming apparatus capable of forming an image by overlaying recording material of at least two colors separates color image data into at least two color component image data, and performs a first correction in consideration of a light-shielding effect and a second correction so as to maintain a density ratio of each color component image data. Then, in accordance with a density value of a second color component image data applied with the first correction, either a first corrected result or a second corrected result is selected. Thereby, decrease of a density value caused by the light-shielding effect is corrected, further correction for maintaining color balance can be performed.