record_screen.py

# syntax: python record_screen.py <output_file_name.avi> <fps> <monitor_id>
# example: python record_screen.py /local/test.avi 20 1

# on user2bmb@arcturus
# conda activate screenrecording
# (screenrecording) user2bmb@arcturus ~/vnikitin $python record_screen.py /local/test.avi 20 3
from mss import mss
from PIL import Image
import cv2
import time
import numpy as np
import sys

def capture_screenshot(mid):
    # Capture entire screen
    with mss() as sct:
        #print(sct.monitors)
        monitor = sct.monitors[mid]
        sct_img = sct.grab(monitor)
        return Image.frombytes('RGB', sct_img.size, sct_img.bgra, 'raw', 'RGBX')

output = sys.argv[1]#"video.avi"
fps = int(sys.argv[2])#20
monitor_id = int(sys.argv[3])#1
width,height =capture_screenshot(monitor_id).size
fourcc = cv2.VideoWriter_fourcc(*'mp4v')
out = cv2.VideoWriter(output, fourcc, fps , (width, height))

print(f'{fps=},{monitor_id=},{output=}')
t = time.time()
while True:
    try:
        image=capture_screenshot(monitor_id)
        out.write(np.asarray(image))
        mtime = time.time()-t
        print(f'\rrecording {mtime:0.1f}s', end="\r")        
    except KeyboardInterrupt:
        print('done')
        break

out.release()
cv2.destroyAllWindows()