An image processing method for processing an input image is provided. The image processing method includes the following steps: selecting a pixel of the input image; determining if the pixel is a first image edge according to at least one first calibrated pixel and at least one second pixel in the input image, in which the first calibrated pixel corresponds to at least one first pixel in the input image; and replacing a high frequency component of at least one channel of the pixel with a first calibrating high frequency component to generate a calibrated pixel if the pixel is not the first image edge, and maintaining the pixel as the calibrated pixel if the pixel is the first image edge.