OpenCV detect camera but return no image feed, while guvcview does

Question

Currently, I'm running some python code on my Ubuntu VM. The VM detects and connects to my Logitech C920, Here is the code I used to connect to the cam:

stream = cv2.VideoCapture(-1)
time.sleep(10.0)
if not (stream.isOpened()):
    print("Failed to get Video Capture")

I gave it 10 secs just to make sure that the cam fully loads before extracting the frame from the live feed. I used cv2.imshow() to view the frame and it is all black even though the camera is connected and greenlit when the code ran.

I noticed that the app Cheese has the same problems while guvcview works fine. Does anyone have any ideas about what may happen? Its been a couple days since I stuck with this problem so any help would be fantastic!

P.S: I found a relevant question on Stack overflow as well: Webcam doesn't read through OpenCV but does with guvcview but there is no answer yet

score 0 · Answer 1 · answered Oct 05 '20 at 04:56

0

Try setting indices other than -1 :

import cv2 ,time
stream = cv2.VideoCapture(0)
time.sleep(10.0)
if not (stream.isOpened()):
    print("Failed to get Video Capture")
else:
    while(True): 
        ret, frame = stream.read() 
        cv2.imshow('frame', frame) 
        if cv2.waitKey(1) & 0xFF == ord('q'): 
            break

answered Oct 05 '20 at 04:56

Subasri sridhar

809
5
13

Thanks. I tried with 0 and some other indexes already. The code detects and triggers the camera as the LED on the cam lit up, but still no image – Minh Duc Pham Oct 05 '20 at 16:33

OpenCV detect camera but return no image feed, while guvcview does

1 Answers1