Not Able to Access CSI Camera in Jetson Nano DLI Course Container

Robotics & Edge Computing Jetson & Embedded Systems Jetson Nano
1

First, I would like to thank you Jetson Nano DLI course teem, and Nvidia for such a valuable course.

I am trying to run CSI camera inside the course container, but I am not able to run the CSI camera inside the container.
Jetson Nano used version B01 (the one comes with two CSI camera slots)
Camera used : CSI camera (Raspberry Pi camera V2.1)
The camera is connected to the first slot.

WhatsApp Image 2020-10-19 at 10.17.40 PM
WhatsApp Image 2020-10-19 at 10.17.40 PM736Ɨ900 62 KB

Docker run command:

sudo docker run --runtime nvidia -it --rm --network host     --volume ~/nvdli-data:/nvdli-nano/data     --device /dev/video0     nvcr.io/nvidia/dli/dli-nano-ai:v2.0.0-r32.4.3

checking camera command works fine

!ls -ltrh /dev/video*
crw-rw---- 1 root video 81, 0 Oct 19 19:00 /dev/video0

Initializing the camera does not work

from jetcam.csi_camera import CSICamera

camera = CSICamera(width=224, height=224)

It is giving me this error:

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

RuntimeError: Could not read image from camera.

During handling of the above exception, another exception occurred:

RuntimeError                              Traceback (most recent call last)
<ipython-input-2-dae08cdf7ca7> in <module>
      1 from jetcam.csi_camera import CSICamera
      2 
----> 3 camera = CSICamera(width=224, height=224)

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

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

Even though the camera works fine on the jetson outside the container. I cloned the Jetcam repo and run the notebook outside the container. it worked fine.

Could you please help me with this issue!?
Also, I hope you open a special section for DLI course issues so it becomes easier to search for all issues in one place.

2

Hi @anasmk, please add the --volume /tmp/argus_socket:/tmp/argus_socket option to your docker run command when launching the container:

sudo docker run --runtime nvidia -it --rm --network host     --volume ~/nvdli-data:/nvdli-nano/data     --volume /tmp/argus_socket:/tmp/argus_socket    --device /dev/video0     nvcr.io/nvidia/dli/dli-nano-ai:v2.0.0-r32.4.3

Then CSI camera should work from inside the container - sorry about that, we have updated the DLI course documentation to reflect that. For more info, please see this post:

https://forums.developer.nvidia.com/t/issues-downloading-and-running-docker-for-getting-started-with-ai-dli-course/156910/7

2 Likes
3

Thanks a lot @dusty_nv it works fine now.

4

Hey,

I had the same issue and adding /tmp/argus_socket to the docker volumes worked for me initially. I am now having an issue where, when I halt the notebook kernel and attempt to open anything else that reads from the camera, I get the same ā€œRuntimeError: Could not initialize camera.ā€ error.

Steps to reproduce:
docker image dli-nano-ai:v2.0.0-r32.4.3
Run a notebook cell that accesses the camera with jetcam.csi_camera CSICamera
Shut down the kernel
Open it again (or any other nb with similar camera access method)
Try to run
Receive error

Iā€™m able to solve it with a complete reboot of the nano. Stopping and restarting the container does not fix the issue. Itā€™s almost like the camera does not close properly when the notebook kernel stops.

Any help would be appreciated!

Thanks.

6

Hi @jeo5015, after you stop the container, can you run this command from your host device:

$  sudo systemctl restart nvargus-daemon

Then start the container and try the camera again. Also, I believe there should be a cell near the end of the notebook that properly shuts down the camera.

3 Likes
7

Thanks! That works to avoid rebooting the device but I still have to kill the container and restart nvargus-daemon after every time I access the camera. Could you point me to a snippet of code to shut down the camera? I looked in all of the DLI notebooks and they only mention to shutdown the kernels. Thanks again for your help!

8

@dusty_nv never mind, I figured it out myself.

camera.cap.release() will do it. It is supposed to be triggered at exit according to this [1] but for some reason it isnā€™t working automatically for me.

[1] jetcam/csi_camera.py at master Ā· NVIDIA-AI-IOT/jetcam Ā· GitHub

9

Ah sorry, you appear to be correct - you could try adding a cell to the end of the notebook and running this to see if it improves the behavior on your system:

camera.cap.release()

If that alone doesnā€™t help, you also might want to add del camera after that line and see if that works.

1 Like
10

Ah ok, thank you - I figured that might help. I will talk with the DLI folks to see about adding that into the notebook.

1 Like
11

I had the same problem; I solved it this way:
Under the cell which contains:
camera.unobserve(update_image, names=ā€˜valueā€™)
I inserted a new cell which contains:
camera.running = False
camera.cap.release()

and this solves the problem. The release command releases the camera; the running=False is necessary to prevent an error.
Randy