Face Detection with Python using OpenCV

Face detection is a computer vision technology that helps to locate/visualize human faces in digital images, videoes and real time detection using cameraes. With the advent of technology, face detection has gained a lot of importance in many recognition systems, for different purpose .

Installation

You need to install opencv library.

Run this command to install it (opencv for python3):

pip3 install opencv-contrib-python

Then import the package in your code (file.py):

import cv2

Recognize Face using OpenCV

Download the dependencies files:

1. haarcascade_frontalface_default.xml.
2. haarcascade_eye.xml.

Then run the following code and it will perform face detection on the given image.

import cv2

face_cascade = cv2.CascadeClassifier(
    '/Users/wesam/Documents/f/Real-time-detection-using-OpenCV-main 2/haarcascade_frontalface_default.xml')


eye_cascade = cv2.CascadeClassifier(
    '/Users/wesam/Documents/f/Real-time-detection-using-OpenCV-main 2/haarcascade_eye.xml')

cap = cv2.VideoCapture(0)

while 1:
    ret, img = cap.read()
    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)
        roi_gray = gray[y:y + h, x:x + w]
        roi_color = img[y:y + h, x:x + w]

        eyes = eye_cascade.detectMultiScale(roi_gray)
        for (ex, ey, ew, eh) in eyes:
            cv2.rectangle(roi_color, (ex, ey),
                          (ex + ew, ey + eh), (0, 255, 0), 2)

    cv2.imshow('img', img)
    k = cv2.waitKey(30) & 0xff
    if k == 27:
        break

cap.release()
cv2.destroyAllWindows()

NOTE:You have to change the path of files base on yours, cv2.CascadeClassifier(your file path)

After running the code, it will draw rectangles around the faces and eyes as shown in the output sample below.

Face.mov

Learning Rerences

• YouTube video