OpenCV VideoCapture is not functioning when deployed in Ubuntu server

Python
1

Hi, I’m trying to open webcam using OpenCV after deploying the code in Ubuntu server. But am not able to open it and getting following error.

[ WARN:0] global /tmp/pip-req-build-rcdoave0/opencv/modules/videoio/src/cap_v4l.cpp (890) open VIDEOIO(V4L2:/dev/video1): can’t open camera by index

I tried to change parameters in cv2.VideoCapture(i) where i=[‘cv2.CAP_V4L2’,0,-1,1] but its not working.

Note: Its working fine with cv2.VideoCapture(0) in local laptop(windows 10) but its not working when deployed in server.

Please help me to resolve the issue.

2

welcome.

CAP_V4L (apiPreference) wants paths such as /dev/video0

CAP_FFMPEG also wants paths

on Windows, CAP_DSHOW and CAP_MSMF (dshow successor/evolution) open video devices by index

3

Hi, Thanks for the reply.
Inorder to open webcam in Ubuntu server without any paths, just wants to call by index,
what is the process that i need to follow?

4

try this. what does it say?

import cv2 as cv
camera_backends = cv.videoio_registry.getCameraBackends()
print(camera_backends)
print([
    cv.videoio_registry.getBackendName(apipref)
    for apipref in camera_backends
])

https://docs.opencv.org/master/de/db1/group__videoio__registry.html#gaf6e7163ade0d35b946c3ccccaf504e3e

5

Is this Ubuntu server on your local computer or external server?

Usually external servers don’t have webcams.
And external server also can’t access your local webcam.

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