Unable to detect USB camera












1















I am trying to use 5 USB cameras on Ubuntu 18.04.1 LTS in python3.6 using opencv3.4.1 through a simple program. I am just using 'cv2.videoCapture()' and then after reading the result use 'cv2.imshow()'.
Individually all cameras work fine, but as I connect them all together the following happens:



Mostly all cameras are successfully detected in start and are listed in lsusb as well as ls /dev/video*, but as I try to use them through my code in python one of these 5 cameras disappear and error like



 VIDEOIO ERROR: V4L: index 0 is not correct!


is printed.A nd after that either ls /dev/video* does not show that camera or the camera name e.g. video0 is automatically changed to e.g. video6. I know if we restart PC the device names are changed but in this case I am not rebooting.



Sometimes the cameras are enlisted in both lsusb as well as in ls /dev/video* but while using select timeout appears.



Let me know if you need further information.










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  • Can guvcview open multiple streams simultaneously without issue?

    – Android Dev
    Jan 18 at 16:15


















1















I am trying to use 5 USB cameras on Ubuntu 18.04.1 LTS in python3.6 using opencv3.4.1 through a simple program. I am just using 'cv2.videoCapture()' and then after reading the result use 'cv2.imshow()'.
Individually all cameras work fine, but as I connect them all together the following happens:



Mostly all cameras are successfully detected in start and are listed in lsusb as well as ls /dev/video*, but as I try to use them through my code in python one of these 5 cameras disappear and error like



 VIDEOIO ERROR: V4L: index 0 is not correct!


is printed.A nd after that either ls /dev/video* does not show that camera or the camera name e.g. video0 is automatically changed to e.g. video6. I know if we restart PC the device names are changed but in this case I am not rebooting.



Sometimes the cameras are enlisted in both lsusb as well as in ls /dev/video* but while using select timeout appears.



Let me know if you need further information.










share|improve this question

























  • Can guvcview open multiple streams simultaneously without issue?

    – Android Dev
    Jan 18 at 16:15
















1












1








1








I am trying to use 5 USB cameras on Ubuntu 18.04.1 LTS in python3.6 using opencv3.4.1 through a simple program. I am just using 'cv2.videoCapture()' and then after reading the result use 'cv2.imshow()'.
Individually all cameras work fine, but as I connect them all together the following happens:



Mostly all cameras are successfully detected in start and are listed in lsusb as well as ls /dev/video*, but as I try to use them through my code in python one of these 5 cameras disappear and error like



 VIDEOIO ERROR: V4L: index 0 is not correct!


is printed.A nd after that either ls /dev/video* does not show that camera or the camera name e.g. video0 is automatically changed to e.g. video6. I know if we restart PC the device names are changed but in this case I am not rebooting.



Sometimes the cameras are enlisted in both lsusb as well as in ls /dev/video* but while using select timeout appears.



Let me know if you need further information.










share|improve this question
















I am trying to use 5 USB cameras on Ubuntu 18.04.1 LTS in python3.6 using opencv3.4.1 through a simple program. I am just using 'cv2.videoCapture()' and then after reading the result use 'cv2.imshow()'.
Individually all cameras work fine, but as I connect them all together the following happens:



Mostly all cameras are successfully detected in start and are listed in lsusb as well as ls /dev/video*, but as I try to use them through my code in python one of these 5 cameras disappear and error like



 VIDEOIO ERROR: V4L: index 0 is not correct!


is printed.A nd after that either ls /dev/video* does not show that camera or the camera name e.g. video0 is automatically changed to e.g. video6. I know if we restart PC the device names are changed but in this case I am not rebooting.



Sometimes the cameras are enlisted in both lsusb as well as in ls /dev/video* but while using select timeout appears.



Let me know if you need further information.







usb video webcam camera image-processing






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Jan 18 at 8:12









Codito ergo sum

1,5023825




1,5023825










asked Jan 18 at 3:08









learning never endslearning never ends

62




62













  • Can guvcview open multiple streams simultaneously without issue?

    – Android Dev
    Jan 18 at 16:15





















  • Can guvcview open multiple streams simultaneously without issue?

    – Android Dev
    Jan 18 at 16:15



















Can guvcview open multiple streams simultaneously without issue?

– Android Dev
Jan 18 at 16:15







Can guvcview open multiple streams simultaneously without issue?

– Android Dev
Jan 18 at 16:15












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