Python+OpenCV实现人脸检测

import numpy as np
import cv2

face_patterns = cv2.CascadeClassifier('D:\python36\Lib\site-packages\cv2\data\haarcascade_frontalface_default.xml')

# 从摄像头中取得视频
cap = cv2.VideoCapture(0)

# 获取视频播放界面长宽
width = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH) + 0.5)
height = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT) + 0.5)

# 定义编码器 创建 VideoWriter 对象
fourcc = cv2.VideoWriter_fourcc(*'mp4v') # Be sure to use the lower case
out = cv2.VideoWriter('output.mp4', fourcc, 20.0, (width, height))

while(cap.isOpened()):
    #读取帧摄像头
    ret, frame = cap.read()
    if ret == True:
        faces = face_patterns.detectMultiScale(frame, scaleFactor=1.1, minNeighbors=5, minSize=(100, 100))
        for (x, y, w, h) in faces:
            cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 255, 0), 2)

        #在窗口展示视图
        cv2.imshow('My Camera',frame)

        #键盘按 Q 退出
        if (cv2.waitKey(1) & 0xFF) == ord('q'):
            break
    else:
        break

# 释放资源
out.release()
cap.release()
cv2.destroyAllWindows()