Disclosed is a driving method of a display device that includes, for example, setting a luminance increase gain based on a chroma of an RGB data of an input image; modulating the RGB data of the input image based on the luminance increase gain to generate an RGB data of a first image; substituting a W data for common components of the RGB data of the first image and converting the RGB data of the first image to an RGBW data of a second image; and encoding the RGBW data of the second image into an RGBW data of a third image such that a number of bits of the RGBW data of the third image is less than a number of bits of the RGBW data of the second image.