1 import cv2 as cv
 2 def face_detect_demo():
 3     # 将图片转化为灰度图片
 4     gray = cv.cvtColor(img,cv.COLOR_BGR2GRAY)
 5     # 加载特征数据
 6     face_detector = cv.CascadeClassifier('D:/Opencv/opencv/sources/data/haarcascades/haarcascade_frontalface_default.xml')
 7     faces = face_detector.detectMultiScale(gray)
 8     for x,y,w,h in faces:
 9         cv.rectangle(img,(x,y),(x+w,y+h),color=(0,255,0),thickness=2)
10     cv.imshow('result',img)
11 # 加载图片
12 img = cv.imread('C:/Users/87823/Desktop/Aaron_Ecke.jpg')
13 face_detect_demo()
14 cv.waitKey(0)
15 cv.destroyAllWindows()