1. An image processing apparatus which generates a plurality of subframe images from a frame image comprising pixels each of which has pixel values for each color component, and outputs the plurality of subframe images, comprising: an identification unit configured to identify, for each pixel in the frame image, minimum pixel values for each color component from pixel values of surrounding pixels for each color component, wherein the surrounding pixels are positioned around the pixel, and identifying, as a common pixel value, a minimum value in the minimum pixel values identified for each color component; a generation unit configured to generate a preprocessed image which can be obtained by replacing a pixel value of each pixel in the frame image with the common pixel value identified for the pixel by said identification unit; a low-pass filtering unit configured to generate a first subframe image by applying a low-pass filter to the preprocessed image; a subtraction unit configured to generate, as a second subframe image, a difference image between the frame image and the first subframe image; and an output unit configured to output the first subframe image and the second subframe image.