python-3.x - 我正在执行 face_detection 程序，但通过显示一些警告，输出没有出现

Question

import cv2
import numpy as np
# https://github.com/Itseez/opencv/tree/master/data/haarcascade
face_cascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')

videocapture = cv2.VideoCapture(0)
scale_factor = 1.3

while 1:
    ret, pic = videocapture.read()

    faces = face_cascade.detectMultiScale(pic, scale_factor, 5)
    for(x, y, w, h) in faces:
        cv2.rectangle(pic, (x, y), (x + w, y + h), (255, 0, 0), 2)
        font = cv2.FONT_HERSHEY_SIMPLEX
        cv2.putText(pic, 'Me', (x, y), font, 2, (255, 255, 255), 2, cv2.LINE_AA)

        print("Number of faces found {} " .format(len(faces)))
        cv2.imshow('faces', pic)
        k = cv2.waitKey(30) & 0xff
        if k == 2:
            break
            cv2.destroyAllWindows()

[警告：0] 全局 C:\Users\appveyor\AppData\Local\Temp\1\pip-req-build-2y91i_7w\opencv\modules\videoio\src\cap_msmf.cpp (435) `匿名命名空间':: SourceReaderCB::~SourceReaderCB 终止异步回调

标签： python-3.xnumpyface-detectioncv2opencv-python

Answer 1

我得到了这个警告的答案，因为我没有允许我的相机启动，所以在允许我的相机后它已经成功运行