import cv2 filename = 'pic.jpg' def detect(filename): face_cascade = cv2.CascadeClassifier('./haarcascade_frontalface_default.xml') img = cv2.imread('pic.jpg') print(1) gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) faces = face_cascade.detectMultiScale(gray,1.3,5) for (x,y,w,h) in faces: img = cv2.rectangle(img,(x,y),(x+w,y+h),(255,0,0),2) cv2.namedWindow("Image") cv2.imshow("Image",img) cv2.waitKey(0) detect(filename)