face_detect_from_camera.py

import cv2
import matplotlib.pyplot as plt
import numpy as np

face_cascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')

webcam=cv2.VideoCapture(1)
cv2.namedWindow("faceWindow", cv2.WINDOW_GUI_NORMAL)
PADDING = 10
try:
    while webcam.isOpened():
        _,frame = webcam.read()
        
        gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
        faces = face_cascade.detectMultiScale(gray, 1.4, 5)
        print(faces)
        for (x, y, w, h) in faces:
            x1 = x-PADDING
            y1 = y-PADDING
            x2 = x+w+PADDING
            y2 = y+h+PADDING

            frame = cv2.rectangle(frame,(x1, y1),(x2, y2),(255,0,0),3)
        cv2.imshow('FaceWindow', frame)
        if cv2.waitKey(20)&0xFF==27:
            break
except KeyboardInterrupt:
    print("Interrupted")
finally:
    webcam.release()
    cv2.destroyAllWindows()
    
    
## OR ##
video_capture = cv2.VideoCapture(1)

while True:
    # Capture frame-by-frame
    ret, frame = video_capture.read()

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

    faces = face_cascade.detectMultiScale(
        gray,
        scaleFactor=1.1,
        minNeighbors=5,
        minSize=(30, 30)
    )

    # 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()