OPENCV cv2.VideoCapture()

Hi all! I’m looking for a solution to my problem! I am using opencv for stereo vision and want to try to get 2 parallel videos from my cameras (on UBUNTU and WIN). I am using camR and camL with cv2.VideoCapture(). But when I try to get Videoflow I can’t do it. I only receive video from 1 camera (on WIN). I was thinking about threads but read that threads don’t help in this case. But on Ubuntu I got 2 videos (but not stable). Can you help me?

import numpy as np
import cv2
import torch
device = torch.device('cuda')

# Call the two cameras
CamR= cv2.VideoCapture(1)
CamL= cv2.VideoCapture(2)
while True:
    retR, frameR=
    retL, frameL =
    grayR= cv2.cvtColor(frameR,cv2.COLOR_BGR2GRAY)
    # grayL = cv2.cvtColor(frameL, cv2.COLOR_BGR2GRAY)
    # retR, cornersR = cv2.findChessboardCorners(grayR, (4, 4), None)
    cv2.imshow('imgR', frameL)
    # print(retR)
    if cv2.waitKey(10) & 0xFF == ord('q'):   # Push the space bar and maintan to exit this Programm

(P.S. I checked number of each cam).