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Python Face Recognition and Face Detection Face Detection in Python Using a Webcam by Shantnu Tiwari 174 Comments data-science machine-learning Tweet Share Email Table of Contents

Pre-requisites The Code Test! Next Steps Want to know more? Remove ads This tutorial is a follow-up to Face Recognition in Python, so make sure you’ve gone through that first post.

As mentioned in the first post, it’s quite easy to move from detecting faces in images to detecting them in video via a webcam - which is exactly what we will detail in this post.

Before you ask any questions in the comments section:

Do not skip over the blog post and try to run the code. You must understand what the code does not only to run it properly but to troubleshoot it as well. Make sure to use OpenCV v2. You need a working webcam for this script to work properly. Review the other comments/questions as your questions have probably already been addressed. Thank you.

Free Bonus: Click here to get the Python Face Detection & OpenCV Examples Mini-Guide that shows you practical code examples of real-world Python computer vision techniques.

Note: Also check out our updated tutorial on face detection using Python.

Pre-requisites OpenCV installed (see the previous blog post for details) A working webcam

Remove ads The Code Let’s dive straight into the code, taken from this repository.

import cv2 import sys

cascPath = sys.argv[1] faceCascade = cv2.CascadeClassifier(cascPath)

video_capture = cv2.VideoCapture(0)

while True:

Capture frame-by-frame

ret, frame = video_capture.read()

gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)

faces = faceCascade.detectMultiScale(
    gray,
    scaleFactor=1.1,
    minNeighbors=5,
    minSize=(30, 30),
    flags=cv2.cv.CV_HAAR_SCALE_IMAGE
)

# Draw a rectangle around the faces
for (x, y, w, h) in faces:
    cv2.rectangle(frame, (x, y), (x+w, y+h), (0, 255, 0), 2)

# Display the resulting frame
cv2.imshow('Video', frame)

if cv2.waitKey(1) & 0xFF == ord('q'):
    break

When everything is done, release the capture

video_capture.release() cv2.destroyAllWindows()

shantnu / FaceDetect

Face recognition #37

Capture frame-by-frame

When everything is done, release the capture