USB Camera not recognized

Autonomous Machines Jetson & Embedded Systems Jetson Nano
,
1

Hello,

I am reporting a common struggle faced by novice Jetson Nano developers
To Initial USB Camera interfaced to Jetson Nano
Steps followed
[1]: !ls -ltrh /dev/video*
​Output: crw-rw----+ 1 root video 81, 0 Sep 2 14:53 /dev/video0
[2] $ v4l2-ctl -d /dev/video0 --list-formats-ext
gst-launch-1.0 -v v4l2src device=/dev/video1 ! video/x-raw,framerate=30/1,width=1280,height=720 ! xvimagesink
Setting pipeline to PAUSED …
Pipeline is live and does not need PREROLL …
ERROR: from element /GstPipeline:pipeline0/GstV4l2Src:v4l2src0: Internal data stream error.
Additional debug info:
gstbasesrc.c(3055): gst_base_src_loop (): /GstPipeline:pipeline0/GstV4l2Src:v4l2src0:
streaming stopped, reason not-negotiated (-4)
ERROR: pipeline doesn’t want to preroll.
Setting pipeline to PAUSED …
Setting pipeline to READY …
Setting pipeline to NULL …
Freeing pipeline …

[3] $ gst-launch-1.0 -v v4l2src device=/dev/video1 ! video/x-raw,framerate=30/1,width=1280,height=720 ! xvimagesink
Setting pipeline to PAUSED …
Pipeline is live and does not need PREROLL …
ERROR: from element /GstPipeline:pipeline0/GstV4l2Src:v4l2src0: Internal data stream error.
Additional debug info:
gstbasesrc.c(3055): gst_base_src_loop (): /GstPipeline:pipeline0/GstV4l2Src:v4l2src0:
streaming stopped, reason not-negotiated (-4)
ERROR: pipeline doesn’t want to preroll.
Setting pipeline to PAUSED …
Setting pipeline to READY …
Setting pipeline to NULL …
Freeing pipeline …

RuntimeError Traceback (most recent call last)
/usr/local/lib/python3.6/dist-packages/jetcam-0.0.0-py3.6.egg/jetcam/usb_camera.py in init(self, *args, **kwargs)
23 if not re:
—> 24 raise RuntimeError(‘Could not read image from camera.’)
25

RuntimeError: Could not read image from camera.

During handling of the above exception, another exception occurred:

RuntimeError Traceback (most recent call last)
in
2
3 #TODO change capture_device if incorrect for your system
----> 4 camera = USBCamera(width=224, height=224, capture_width=640, capture_height=480, capture_device=0)

/usr/local/lib/python3.6/dist-packages/jetcam-0.0.0-py3.6.egg/jetcam/usb_camera.py in init(self, *args, **kwargs)
26 except:
27 raise RuntimeError(
—> 28 ‘Could not initialize camera. Please see error trace.’)
29
30 atexit.register(self.cap.release)

RuntimeError: Could not initialize camera. Please see error trace.

Please let me know which step is missed?
USB Camera is still not functional

Best Regards
Sreepada

3

Some reason to use video1 even /dev/video0 is there?

Blockquote
gst-launch-1.0 -v v4l2src device=/dev/video1 ! video/x-raw,framerate=30/1,width=1280,height=720 ! xvimagesink
[3] $ gst-launch-1.0 -v v4l2src device=/dev/video1 ! video/x-raw,framerate=30/1,width=1280,height=720 ! xvimagesink

4

Hi,
Please check Jetson Nano FAQ
Q: I have a USB camera. How can I lauch it on Jetson Nano?
Looks like your format is not set. Please set the exact mode including width,height,format,framerate.

1 Like
5

Hello Dane,
Thank you for sharing Jetson Nano FAQ
USB Camera is functional.

$ gst-launch-1.0 -v v4l2src device=/dev/video0 ! ‘video/x-raw,format=YUY2,width=1280,height=720,framerate=10/1’ ! xvimagesink -ev

I have following suggestion,

  1. Please share the Jetson Nano FAQs link in Hello Camera URL

It helps novice to quickly follow the procedure

Best Regards
Sreepada

6

Hello MtHiker,
thank you for the feedback.
I observed that, when USB camera is unplug and connect back the device=/dev/video0 or /dev/video1 was dynamically updated.
I am able to run video now with
$ gst-launch-1.0 -v v4l2src device=/dev/video0 ! ‘video/x-raw,format=YUY2,width=1280,height=720,framerate=10/1’ ! xvimagesink -ev

7

Hi,
Please try

camera = USBCamera(width=224, height=224, capture_fps=10, capture_width=1280, capture_height=720, capture_device=0)
8

Hi,

USB Camera is functional with the above command.
Topic can be closed.

Thank you

Best Regards
Sreepada