1. An image processing apparatus comprising: an edge classification section for distinguishing an edge pattern of an edge to be included in an expanded image of a compressed image and classifying the edge by using the distinguished edge pattern, wherein the edge classification section distinguishes the edge pattern by using identification data assigned to each of the pixels of the compressed image, the identification data indicating a half tone region or a high resolution region with respect to each of the pixels, and quantized data of each of the pixels.