1. A method for example-based face hallucination on a face hallucination system, comprising: preparing a training database with a plurality of training images and inputting a low resolution (LR) face image to be hallucinated; projecting said plurality of training images of said training database and said LR face image onto a same manifold by using manifold learning, where y L representing projected said LR face image and y train representing projected said training images; selecting a training set best matching y L from N projected training images y train , where N is not greater than number of said plurality of training images; learning a set of basis images by using basis decomposition on said training set and y L , said set of basis images including a high and low resolution prototype faces in said training set and a low resolution prototype face of y L ; and reconstructing a high resolution face image of said LR face image by using said basis images.