dlib提取人臉區域及關鍵點檢測

shape_predictor = "./shape_predictor_68_face_landmarks.dat" 
detector = dlib.get_frontal_face_detector()
predictor = dlib.shape_predictor(shape_predictor)

frame = cv2.imread(imgfullpath)
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
rects = detector(gray,0)   #也可以對彩色圖像提取人臉區域

for rect in rects:
    face_img = gray[max(rect.top(),1):min(rect.bottom(),frame.shape[0]-1), max(rect.left(),1):min(rect.right(),frame.shape[1]-1)]    #提取的人臉區域有可能超出圖像的邊界
            
    #### landmarks ###
    shape = predictor(gray,rect)
    shape = face_utils.shape_to_np(shape)

    i = 1
    for (x,y) in shape:
        cv2.circle(face_img,(x,y),1,(0,255,0),-1)
        cv2.putText(face_img, str(i), (x-rect.left(), y-rect.top()),cv2.FONT_HERSHEY_SIMPLEX, 0.3, (0, 0, 255), 1)
        i += 1

cv2.imshow('frame',frame)
cv2.waitkey(0)