opencv - Capture video data from screen in Python

Question

Is there a way with Python (maybe with OpenCV or PIL) to continuously grab frames of all or a portion of the screen, at least at 15 fps or more? I've seen it done in other languages, so in theory it should be possible.

I do not need to save the image data to a file. I actually just want it to output an array containing the raw RGB data (like in a numpy array or something) since I'm going to just take it and send it to a large LED display (probably after re-sizing it).

Answer 1

There is an other solution with mss which provide much better frame rate. (Tested on a Macbook Pro with MacOS Sierra)

import numpy as np
import cv2
from mss import mss
from PIL import Image

mon = {'left': 160, 'top': 160, 'width': 200, 'height': 200}

with mss() as sct:
    while True:
        screenShot = sct.grab(mon)
        img = Image.frombytes(
            'RGB', 
            (screenShot.width, screenShot.height), 
            screenShot.rgb, 
        )
        cv2.imshow('test', np.array(img))
        if cv2.waitKey(33) & 0xFF in (
            ord('q'), 
            27, 
        ):
            break