The present invention discloses a method to construct template images for recognition, including the steps of: obtaining a plurality of digitized images belonging to n categories; for all categories, extracting common features for images belonging to a category; comparing common features of said category with common features of other categories other than category, to obtain discriminating features for the category; and including such features into representative features to obtain template images. A method to recognize an input image using the template images so obtained is also disclosed.