1. An image display device for displaying an image according to image data, comprising: a detection unit for detecting bright parts of the image that are adjacent to dark parts of the image, from the image data; a smoothing unit coupled to the detection unit, for smoothing the bright parts of the image that are adjacent to the dark parts of the image by filtering the image data, leaving the dark parts of the image unsmoothed; and a display unit coupled to the smoothing unit, for displaying the image data, including the smoothed bright parts of the image and the unsmoothed dark parts of the image.