1. An image processing apparatus for retrieving a specific pattern of an image comprising: a unit for dividing the image into a plurality of block regions, each of the block regions having a predetermined size; a unit for creating a map image comprising a plurality of pixels, each of the pixels corresponding to one of the block regions by one to one; a unit for extracting features of the image for each of the block regions; a unit for deciding whether or not the extracted feature meets a predetermined condition; a unit for labeling the pixel on the map image based on a result of the decision, the pixel corresponding to the block region of which feature meets the condition; a unit for detecting a predetermined pattern for specifying a search region on the image from the labeled map image; a unit for specifying the search region based on a position on the map image in which the predetermined pattern is detected; and a unit for retrieving the specific pattern in the specified search region on the image.