Jan 16
2 min read
Python Machine learning --Capturing and processing video from a webcam
We will use a webcam to capture video data. Let’s see how to capture the video
from the webcam using OpenCV-Python.
How to do it…
1. Create a new Python file, and import the following packages:
import cv2
2. OpenCV provides a video capture object that we can use to capture images from the webcam. The 0 input argument specifies the ID of the webcam. If you connect a USB
camera, then it will have a different ID:
# Initialize video capture object
cap = cv2.VideoCapture(0)
3. Define the scaling factor for the frames captured using the webcam:
# Define the image size scaling factor
scaling_factor = 0.5
4. Start an infinite loop and keep capturing frames until you press the Esc key.
Read the frame from the webcam:
# Loop until you hit the Esc key
while True:
# Capture the current frame
ret, frame = cap.read()
5. Resizing the frame is optional but still a useful thing to have in your code:
# Resize the frame
frame = cv2.resize(frame, None, fx=scaling_factor, fy=scaling_
factor,
interpolation=cv2.INTER_AREA)
6. Display the frame:
# Display the image
cv2.imshow(‘Webcam’, frame)
7. Wait for 1 ms before capturing the next frame:
# Detect if the Esc key has been pressed
c = cv2.waitKey(1)
if c == 27:
break
8. Release the video capture object:
# Release the video capture object
cap.release()
9. Close all active windows before exiting the code:
# Close all active windows
cv2.destroyAllWindows()
