solution.py

# -*- coding: utf-8 -*-
"""
Spyder Editor

This is a temporary script file.
"""
import cv2

face_cascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')
eye_cascade = cv2.CascadeClassifier('haarcascade_eye.xml')
smile_cascade = cv2.CascadeClassifier('haarcascade_smile.xml')

def detect(gray,frame):
    faces = face_cascade.detectMultiScale(gray,1.3,5)
    if(len(faces)>0):
        for (x,y,w,h) in faces:
            cv2.rectangle(frame,(x,y),(x+w,y+h),(255,0,0),2)
            roi_gray = gray[y:y+h,x:x+w]
            roi_color = frame[y:y+h,x:x+w]
            eyes = eye_cascade.detectMultiScale(roi_gray,1.1,22)
            if(len(eyes)>0):
                for (ex,ey,ew,eh) in eyes:
                    cv2.rectangle(roi_color,(ex,ey),(ex+ew,ey+eh),(0,255,0),2)
            smiles = smile_cascade.detectMultiScale(roi_gray,1.7,22)
            if(len(smiles)>0):
                for (sx,sy,sw,sh) in smiles:
                    cv2.rectangle(roi_color,(sx,sy),(sx+sw,sy+sh),(0,0,255),2)
    return frame

video_capture = cv2.VideoCapture(0)
while True:
    _,frame = video_capture.read()
    gray = cv2.cvtColor(frame,cv2.COLOR_BGR2GRAY)
    canvas = detect(gray,frame)
    cv2.imshow('Video',canvas)
    if(cv2.waitKey(1) & 0xFF==ord('q')):
        break
video_capture.release()
cv2.destroyAllWindows()