a data processor configured to receive first data and to generate second data by performing a sub-pixel rendering process on the first data and changing grayscale values of the first data;

a timing controller configured to control an output of a scan signal and an output of a data signal;

a data driver configured to output the data signal based on the second data; and

a panel having a pixel arrangement structure comprising a plurality of sub-pixels for displaying an image,

wherein the panel consists of:

a first group of pixel rows and columns comprising odd-numbered pixel rows and odd-numbered pixel columns; and

a second group of pixel rows and columns comprising even-numbered pixel rows and even-numbered pixel columns,

wherein first color sub-pixels and second color sub-pixels are alternately arranged in each of the pixel rows and columns of one of the first and second groups, and

wherein third color sub-pixels are arranged only in the pixel rows and columns of another one of the first and second groups.