capture.py

import cv2 as cv
import time

delay = 5

if __name__ == "__main__":
    cap = cv.VideoCapture("/dev/video2")
    if not cap.isOpened():
        print("Cannot open camera")
        exit(1)
    next_grab = time.time()
    while True:
        ret, frame = cap.read()
        frame = cv.rotate(frame, cv.ROTATE_90_CLOCKWISE)
        frame = frame[350:550, 0:800]
        if not ret:
            print("Cannot receive stream")
            exit(1)
        if time.time() - next_grab > 0:
            cv.imshow("frame", frame)
            cv.imwrite(str(int(time.time())) + ".png", frame)
            next_grab = time.time() + delay
        if cv.waitKey(1) == ord('q'):
            cap.release()
            cv.destroyAllWindows()
            exit(0)