opencv python chapter5 人脸检测

import cv2 as cv
from chapter4 import stackImages
faceCascade = cv.CascadeClassifier(r"data/haarcascade_frontalface_default.xml")
frameWidth = 640
frameHeight = 480
cap = cv.VideoCapture(0)
cap.set(3,frameWidth)
cap.set(4,frameHeight)
cap.set(10,130)
while True:
    success ,img = cap.read()
    #人脸识别
    imgGray = cv.cvtColor(img, cv.COLOR_BGR2GRAY)
    faces = faceCascade.detectMultiScale(imgGray, 1.1, 4)
    for (x, y, w, h) in faces:
        cv.rectangle(img, (x, y), (x + w, y + h), (255, 0, 0), 2)
    imgStack = stackImages(1, ([img]))
    cv.imshow("img", imgStack)
    cv.waitKey(1)
    if cv.waitKey(1)& 0xFF ==ord('q'):
        break