In this tutorial, we will introduce the way to detect the number of faces in an image, we will use python opencv to implement it.
1. Import library
import cv2
2. Read an image
im2=cv2.imread(r"member.jpg",0) im=cv2.imread(r"member.jpg")
3. Create a face detector
facedetector=cv2.CascadeClassifier(r"haarcascade_frontalface_default.xml")
4. Detect faces in an image
face=facedetector.detectMultiScale(im2,1.1,5)
5. Ouput the number of faces
print('number of faces:') print(len(face))
6. Show faces in an image
for x,y,z,h in face: cv2.rectangle(im,(x,y),(x+z,y+h),(0,0,225),3) cv2.imshow("facedetective",im) cv2.waitKey(0) cv2.destroyallWindows()