0

I purchased two webcams (Logitech C310 HD Webcam) to use with RaspberryPi (RPi 3 B+ model). When I run individual cameras, they are running fine but when I tried to run both cameras at the same time it didn't run. I came to know that it may be due to less power in Raspberry Pi, so I purchased a powered USB hub (Power USB hub). When I attached both cameras with raspberry pi through a power USB hub, it shows an error.

VIDIOC_QBUF: Invalid argument
    cv2.imshow("frame2",frame2)
cv2.error: OpenCV(3.4.4) /home/pi/packaging/opencv-python/opencv/modules/highgui/src/window.cpp:356: error: (-215:Assertion failed) size.width>0 && size.height>0 in function 'imshow'

My code is:

import cv2
import numpy as np
import imutils
from imutils.video import WebcamVideoStream
from imutils.video import VideoStream

cam1 = WebcamVideoStream(src=0).start()
cam2 = WebcamVideoStream(src=2).start()
#cam1 = VideoStream(src=0).start()
#cam2 = VideoStream(src=2).start()

while (1):
 frame1 = cam1.read()
 cv2.imshow("frame1",frame1)
 frame2 = cam2.read()
 cv2.imshow("frame2",frame2)

 k = cv2.waitKey(5) & 0xFF
 if k == 27:
  break
cam1.release()
cam2.release()
cv2.destroyAllWindows()

With single web camera, above code works fine (when this code modifiy for single cam.) Why there is an error while trying to run two cameras with Raspberry Pi? How I can run two webcams using Raspberry Pi.

2
  • what happens if you use code for one camera and plug in both cameras?
    – jsotola
    Commented Jun 13, 2019 at 15:34
  • In that case, single camera only run. If I used cam1 = WebcamVideoStream(src=0).start(), then first cam run and if I used cam1 = WebcamVideoStream(src=2).start(), then second cam runs. But, whenever I tried to run both cams, it shows error as mentioned in question. Commented Jun 14, 2019 at 4:12

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.