【OpenCV】简单的Python实现人脸检测

参考OpenCV自带的例子，30行python代码实现人脸检测，不得不说，Python这个语言的优势太明显了，几乎把所有复杂的细节都屏蔽了，虽然效率较差，不过在调用opencv的模块时，因为模块都是C语言编写，所以在效率上并不会比用C或者C++编写慢太多。本例子使用自带的级联分类器。

#!/usr/bin/env pythonimport cv2def faceDetect(img, face_cascade):    gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)    faces = face_cascade.detectMultiScale(gray, 1.3, 5)    for (x,y,w,h) in faces:        cv2.rectangle(img,(x,y),(x+w,y+h),(255,0,0),2)    return imgdef main():    cap = cv2.VideoCapture(1)    face_cascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')    while(True):        # Capture frame-by-frame        ret, frame = cap.read()        #frame = imread("2017-02-26-200818.jpg")        # Our operations on the frame come here        if ret == True:            frame = faceDetect(frame, face_cascade)        # Display the resulting frame        cv2.imshow('frame',frame)        if cv2.waitKey(1) & 0xFF == ord('q'):            break    # When everything done, release the capture    cap.release()    cv2.destroyAllWindows()main()