When i plug in usb camera i get 2 devices
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When I plug in the camera to Linux then I get 2 devices /dev/video0 and /dev/video1
Why is that happens and is that normal?
Odd numbered devices do not work.
/dev/v4l/by-path looks like that:
lrwxrwxrwx 1 root root 12 dets 15 01:29 pci-0000:00:14.0-usb-0:14:1.0-video-index0 -> ../../video0
lrwxrwxrwx 1 root root 12 dets 15 01:29 pci-0000:00:14.0-usb-0:14:1.0-video-index1 -> ../../video1
/dev/v4l/by-id looks like that:
lrwxrwxrwx 1 root root 12 dets 15 01:29 usb-_Webcam_C170-video-index0 -> ../../video0
lrwxrwxrwx 1 root root 12 dets 15 01:29 usb-_Webcam_C170-video-index1 -> ../../video1
I tested it with 2 computers(Kubuntu 18.10) and with 4 different cameras. it makes always 2 devices.
linux usb devices v4l
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Paxmees
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add a comment |
up vote
1
down vote
favorite
When I plug in the camera to Linux then I get 2 devices /dev/video0 and /dev/video1
Why is that happens and is that normal?
Odd numbered devices do not work.
/dev/v4l/by-path looks like that:
lrwxrwxrwx 1 root root 12 dets 15 01:29 pci-0000:00:14.0-usb-0:14:1.0-video-index0 -> ../../video0
lrwxrwxrwx 1 root root 12 dets 15 01:29 pci-0000:00:14.0-usb-0:14:1.0-video-index1 -> ../../video1
/dev/v4l/by-id looks like that:
lrwxrwxrwx 1 root root 12 dets 15 01:29 usb-_Webcam_C170-video-index0 -> ../../video0
lrwxrwxrwx 1 root root 12 dets 15 01:29 usb-_Webcam_C170-video-index1 -> ../../video1
I tested it with 2 computers(Kubuntu 18.10) and with 4 different cameras. it makes always 2 devices.
linux usb devices v4l
asked yesterday
Paxmees
62
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Paxmees is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
1
It depends on the camera model. What doesls -l /dev/v4l/by-idlook like? If a camera has an error in its USB device/endpoint descriptors (= within the camera firmware), it might well produce strange results like this.
– telcoM
yesterday
I added details
– Paxmees
yesterday
What does dmesg say (relevant lines at the time shortly after plugging the camera)?
– Hermann
yesterday
add a comment |
up vote
1
down vote
favorite
up vote
1
down vote
favorite
When I plug in the camera to Linux then I get 2 devices /dev/video0 and /dev/video1
Why is that happens and is that normal?
Odd numbered devices do not work.
/dev/v4l/by-path looks like that:
lrwxrwxrwx 1 root root 12 dets 15 01:29 pci-0000:00:14.0-usb-0:14:1.0-video-index0 -> ../../video0
lrwxrwxrwx 1 root root 12 dets 15 01:29 pci-0000:00:14.0-usb-0:14:1.0-video-index1 -> ../../video1
/dev/v4l/by-id looks like that:
lrwxrwxrwx 1 root root 12 dets 15 01:29 usb-_Webcam_C170-video-index0 -> ../../video0
lrwxrwxrwx 1 root root 12 dets 15 01:29 usb-_Webcam_C170-video-index1 -> ../../video1
I tested it with 2 computers(Kubuntu 18.10) and with 4 different cameras. it makes always 2 devices.
linux usb devices v4l
asked yesterday
Paxmees
62
New contributor
Paxmees is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
When I plug in the camera to Linux then I get 2 devices /dev/video0 and /dev/video1
Why is that happens and is that normal?
Odd numbered devices do not work.
/dev/v4l/by-path looks like that:
lrwxrwxrwx 1 root root 12 dets 15 01:29 pci-0000:00:14.0-usb-0:14:1.0-video-index0 -> ../../video0
lrwxrwxrwx 1 root root 12 dets 15 01:29 pci-0000:00:14.0-usb-0:14:1.0-video-index1 -> ../../video1
/dev/v4l/by-id looks like that:
lrwxrwxrwx 1 root root 12 dets 15 01:29 usb-_Webcam_C170-video-index0 -> ../../video0
lrwxrwxrwx 1 root root 12 dets 15 01:29 usb-_Webcam_C170-video-index1 -> ../../video1
I tested it with 2 computers(Kubuntu 18.10) and with 4 different cameras. it makes always 2 devices.
linux usb devices v4l
linux usb devices v4l
asked yesterday
Paxmees
62
New contributor
Paxmees is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked yesterday
Paxmees
62
New contributor
Paxmees is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited yesterday
asked yesterday
Paxmees
62
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Paxmees is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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asked yesterday
Paxmees
62
asked yesterday
Paxmees
62
62
New contributor
Paxmees is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Paxmees is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Paxmees is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
1
It depends on the camera model. What doesls -l /dev/v4l/by-idlook like? If a camera has an error in its USB device/endpoint descriptors (= within the camera firmware), it might well produce strange results like this.
– telcoM
yesterday
I added details
– Paxmees
yesterday
What does dmesg say (relevant lines at the time shortly after plugging the camera)?
– Hermann
yesterday
add a comment |
1
It depends on the camera model. What doesls -l /dev/v4l/by-idlook like? If a camera has an error in its USB device/endpoint descriptors (= within the camera firmware), it might well produce strange results like this.
– telcoM
yesterday
I added details
– Paxmees
yesterday
What does dmesg say (relevant lines at the time shortly after plugging the camera)?
– Hermann
yesterday
1
1
It depends on the camera model. What does
ls -l /dev/v4l/by-id look like? If a camera has an error in its USB device/endpoint descriptors (= within the camera firmware), it might well produce strange results like this.– telcoM
yesterday
It depends on the camera model. What does
ls -l /dev/v4l/by-id look like? If a camera has an error in its USB device/endpoint descriptors (= within the camera firmware), it might well produce strange results like this.– telcoM
yesterday
I added details
– Paxmees
yesterday
I added details
– Paxmees
yesterday
What does dmesg say (relevant lines at the time shortly after plugging the camera)?
– Hermann
yesterday
What does dmesg say (relevant lines at the time shortly after plugging the camera)?
– Hermann
yesterday
add a comment |
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1
It depends on the camera model. What does
ls -l /dev/v4l/by-idlook like? If a camera has an error in its USB device/endpoint descriptors (= within the camera firmware), it might well produce strange results like this.– telcoM
yesterday
I added details
– Paxmees
yesterday
What does dmesg say (relevant lines at the time shortly after plugging the camera)?
– Hermann
yesterday