An image processing device including a storage part storing an error value corresponding to at least one of second pixels in an image display device, the image display device having a display screen, the display screen having a plurality of pixels, the plurality of pixels having a first pixel and the second pixels, the second pixels surrounding a first pixel, a pixel data calculating pixel data corresponding to the first pixel based on a coefficient in response to a gradation of input data in the second pixel and the error value corresponding to the second pixel, a quantized data calculator quantizing the calculated pixel data and calculating quantized data, and an error value calculator corresponding the calculated pixel data and an error value with the quantized data and storing in the storage part.