videocapture(0) and .read returning false every time

asked 2018-03-30 01:00:13 -0500

smoy gravatar image

updated 2019-07-13 04:54:32 -0500

supra56 gravatar image

i have been trying this code, but the ret value is returning false everytime due to which i am unable to load video from my laptop camera please help:

import numpy as np
import cv2
cap = cv2.VideoCapture(0)
while(True):  # check !
    # capture frame-by-frame

    ret, frame =

    if ret: # check ! (some webcam's need a "warmup")
        # our operation on frame come here
        gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)

        # Display the resulting frame
        cv2.imshow('frame', gray)

    if cv2.waitKey(1) & 0xFF == ord('q'):
# When everything is done release the capture
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os, opencv version ? how did you install it ?

are you able to access the camera from another program ? (vlc, mplayer, cheese, etc)

berak gravatar imageberak ( 2018-03-30 01:15:38 -0500 )edit

iam doing it in windows 10 opencv version i have tried is and 2.4.13 i installed from

smoy gravatar imagesmoy ( 2018-03-30 01:33:41 -0500 )edit

yes i can access the camera from my inbuilt camera of windows. @berak

smoy gravatar imagesmoy ( 2018-03-30 01:34:09 -0500 )edit