需要先安装库：dlib/opencv-py/numpy
安装过程有点麻烦需要耐心；
注意修改代码中的图片路径（要完整路径）
在电脑上运营后会弹出识别结果弹窗，点击这个窗口按ESC退出

#!/usr/bin/python
# -*- coding: UTF-8 -*-
import cv2
import dlib
import numpy as np

def plot_rectangle(image, faces):
    for face in faces:
        cv2.rectangle(image, (face.left(), face.top()), (face.right(), face.bottom()), (200,200,0), 1)
    return image

def main():

    img = cv2.imread("/Users/xxx/Documents/python/face/test.jpg")

    gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

    detector = dlib.get_frontal_face_detector()
    dets_result = detector(gray, 1) 

    img_result = plot_rectangle(img.copy(), dets_result)

    cv2.imshow("Faceshow", img_result)
    cv2.waitKey(0)
    cv2.destroyAllWindows()

if __name__ == '__main__':
    main()