Method of driving display panel and display apparatus performing the same

A display apparatus, comprising:

• a display panel;
• and
• a timing controller to control an operation of the display panel,
• wherein the timing controller includes:
• an image analyzer to obtain a first grayscale histogram based on the input image data;
• a gamma compensator to generate a gamma curve by selectively changing an initial gamma curve based on at least one selected from the first grayscale histogram and a predetermined power mode;
• an image processor to generate output image data based on the input image data and the gamma curve;
• and
• an operating frequency selector to change an operating frequency of the display panel from a first frequency to a second frequency lower than the first frequency when the gamma curve is different from the initial gamma curve, wherein, when the gamma curve is different from the initial gamma curve, an image frame corresponding to the output image data is displayed on the display panel based on the second frequency.