Organic light emitting display device including signal processor for modifying image data and driving method thereof

A driving method of an organic light emitting display device comprising a signal processor for modifying image data organized in frames, the method comprising:

• generating scan signals and sequentially outputting the scan signals to scan lines;
• generating data signals and outputting the data signals to data lines;
• generating light sensing signals corresponding to an external light intensity of an environment of the display device;
• storing modified image data output from the signal processor in a frame memory configured to store the image data in units each corresponding to one of the frames, the image data comprising first image data in a first one of the frames that relates to a still image;
• generating image judging signals according to whether subsequent ones of the frames of the image data relate to moving images or still images, comprising generating the image judging signals only if the image data corresponds to the still images;
• generating selection signals by comparing the light sensing signals with reference values, modifying the image data according to the selection signals, and outputting the selection signals and the modified image data from the signal processor;
• not changing the first image data in the frame memory, of the subsequent ones of the frames of the image data, when the subsequent ones of the frames relate to the still image;
• reloading the frame memory from the signal processor output after a reset of the frame memory;
• resetting the frame memory to erase the first image data in the frame memory in a second one of the frames that relates to the still image;
• and
• storing modified first image data in the second one of the frames,
• wherein the modified first image data corresponds to the first image data, and comprises modified pixel saturation and/or brightness values of the first image data.