An image processing method includes the following steps. First, noise of a first image is filtered, and the first image is converted to obtain a luminance signal. Second, the first image is stored and outputted. Third, a color space converting process is performed upon the first image according to the luminance signal to obtain a second image. Fourth, a linear computing is performed upon the second image to obtain a third image. Fifth, the color space converting process is performed according to a third image and the luminance signal to obtain and output a fourth image. Sixth, an error compensation is performed upon the first image and the fourth image, and the fourth image is outputted. Accordingly, a linear operating process and error compensation processing is performed upon the single image to filter the noise of the image, and thus a load of the system is reduced.