import cv2

加载人脸检测分类器

face_cascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')

打开前置摄像头

cap = cv2.VideoCapture(1)

while True: # 读取视频流 ret, frame = cap.read()

# 转为灰度图像
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)

# 检测人脸
faces = face_cascade.detectMultiScale(gray, 1.3, 5)

# 绘制人脸方框
for (x, y, w, h) in faces:
    cv2.rectangle(frame, (x, y), (x+w, y+h), (0, 255, 0), 2)

# 显示视频流
cv2.imshow('frame', frame)

# 按下 q 键退出
if cv2.waitKey(1) & 0xFF == ord('q'):
    break

释放资源

cap.release() cv2.destroyAllWindows(