Face recognition using OpenCV

faces.py

import cv
 
class Detector(object):

    def __init__(self, haar_file):
        self.haar = cv.Load(haar_file)
        self.storage = cv.CreateMemStorage()

    def detect(self, image):
        # parameters for fast detection
        return cv.HaarDetectObjects(image, self.haar, self.storage, 
                                    scale_factor=1.2, min_neighbors=2, flags=cv.CV_HAAR_DO_CANNY_PRUNING )
         

def draw_rect_on_image(rect, image):
    cv.Rectangle(image, 
                 (rect[0], rect[1]),
                 (rect[0] + rect[2], rect[1] + rect[3]),
                 cv.RGB(155, 55, 200), 2)


if __name__ == '__main__':
    cv.NamedWindow('Camera', cv.CV_WINDOW_AUTOSIZE)
 
    capture = cv.CreateCameraCapture(0)

    face_detector = Detector('haarcascade_frontalface_alt.xml')
 
    while True:
        frame = cv.QueryFrame(capture)
       
        cv.Flip(frame, None, 1)

        faces = face_detector.detect(frame)
        if faces:
            for (rect, _) in faces:
                draw_rect_on_image(rect, frame)
        
        cv.ShowImage('Camera', frame)