Exemplary embodiments disclose an image processing method which includes obtaining a binary value by quantizing a value obtained by summing at least one pixel value of an input image and a quantization error value of a neighboring pixel; determining a pixel in which a detail intensity is to be inserted according to the binary value of each pixel; determining the detail intensity to be inserted in the determined pixel; and inserting the determined detail intensity in the determined pixel, wherein the quantization error value of the neighboring pixel is a difference value between an original pixel value of the neighboring pixel and a pixel value quantized with respect to a predetermined constant value.