A digital gamma correction part includes a memory and a selector. The memory is configured to store a basic gamma reference data, a first compensated gamma reference data and a second compensated gamma reference data, where respective data of the first compensated gamma reference data are greater than respective data of the basic gamma reference data, and respective data of the second compensated gamma reference data are less than respective data of the basic gamma reference data. The selector is configured to receive a luminance data determined based on a luminance of a display panel, and to output a gamma reference data by selecting one from the basic gamma reference data, the first compensated gamma reference data and the second compensated gamma reference data based on the luminance data and a gamma converted reference range.