1. A table recognition method of recognizing a frame as a ruled line in a table area of a document image including the table area, the table recognition method comprising the steps of: extracting circumscribing rectangles of connected components of black pixels of the document image; sorting the extracted circumscribing rectangles as character candidates and frame candidates according to information such as an aspect ratio, a number of black pixels and a number of black runs of the extracted circumscribing rectangles; filling the image inside the area of the rectangles which have been sorted as the character candidates with white; and recognizing frames from the rectangles which have been sorted as the frame candidates.