A display device includes a calculator that calculates a number of horizontal pixels and a number of vertical pixels, a determiner that divides pixels of an image into a plurality of pixel groups, determines at least one pixel among the pixels as a first pixel based on a pixel value of the pixels included in each pixel group, and determines at least one pixel except for the first pixel among the pixels as a second pixel, a first image processor that performs an image-enhancement process on the first pixel among pixels to be included in the image to allow a first substance to correspond to a first substance increase rate, and a second image processor that performs an image-enhancement process on the second pixel among the pixels to be included in the image to allow a second substance to correspond to a second substance increase rate.