An apparatus for improving image sharpness includes a pixel detector that labels each of pixels in an image as one of an edge/texture type and a non-edge/texture type, a pixel type determiner that classifies each of the pixels that are labeled as the edge/texture type as one of a border point type pixel, a transition point type pixel, and a peak point type pixel, and a filter. The filter includes a shrinking/expanding filter and a high boost filter, the shrinking/expanding filter filtering the border point type pixels, and the high boost filter subsequently filtering the peak point type pixels and then filtering the transition point type pixels.