Display device and driving method thereof

A method of driving a display device, the method comprising:

• transmitting input image data from a graphics processing unit of the display device to a signal controller of the display device;
• receiving a still image start signal and compressing the input image data into compressed image data;
• storing the compressed image data in a frame memory of the display device;
• and
• generating mixed image data by mixing compression recovered image data and the input image data, and outputting the mixed image data to a display panel of the display device,
• wherein the compression recovered image data is generated by recovering the compressed image data in a first image conversion period, in which a motion picture is converted into a still image.