1. A display control apparatus configured to receive an input image signal and output an output image signal, comprising: a histogram constructer configured to construct a histogram based on a gray value of each pixel of the input image signal; a maximum value determiner configured to determine a maximum value of the output image signal based on the input image signal; and a mapping curve determiner configured to receive the input image signal and determine a mapping curve for generating the output image signal from the input image signal, based on the histogram and the maximum value, wherein: the histogram constructer, the maximum value determiner, and the mapping curve determiner are each formed as an integrated circuit; and the maximum value is configured to be increased as a number of pixels having a highest gray value that the input image signal may have from among the pixels of the input image signal increases.