1. A method of generating an interpolation image by interpolating at least one image unit of an input image in an image display device, the method comprising: an interpolation image generation process, performed by a motion predictor of the image display device, calculating motion vectors from a previous image unit and a subsequent image unit that are continuous and generating the interpolation image using the motion vectors; a motion error boundary detection process, performed by a boundary detector of the image display device, detecting an area, in which a motion error determined from the motion vectors is greater than a predetermined value, as a boundary area of the interpolation image; and a motion compensation process, performed by a motion compensator of the image display device, compensating for a motion error inside the detected boundary area based on a dominant direction of the motion vectors using at least one of the previous image unit and the subsequent image unit.