I am on a Nvidia Jetson Nano with the JetPack4.5 Image from Waveshare. I installed a Virtual Environment with python3.8 and OpenCv.
When I try in my terminal there is no Problem.

(.venv) jetson@nano-4gb-jp451:~/python3.8test$ python
Python 3.8.0 (default, Dec  9 2021, 17:53:27) 
[GCC 8.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import cv2

After that I added the Virtual Environment to my Jupyter Notebook.

pip install --user ipykernel

python -m ipykernel install --user --name=venv
Installed kernelspec venv in /home/jetson/.local/share/jupyter/kernels/venv

In the new venv Notebook I checked the python version, which was corrected.

from platform import python_version
print(python_version())

3.8.0

But when I try to import cv2 the Output is “No module named ‘cv2’

%matplotlib inline

from matplotlib import pyplot as plt
import cv2

image = cv2.imread('TestBild.PNG')

cv2.imwrite('TestBildOut.PNG', image)

print(image.shape)
plt.imshow(cv2.cvtColor(image, cv2.COLOR_BGR2RGB))
plt.show()

---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
Cell In[3], line 4
      1 get_ipython().run_line_magic('matplotlib', 'inline')
      3 from matplotlib import pyplot as plt
----> 4 import cv2
      6 image = cv2.imread('TestBild.PNG')
      8 cv2.imwrite('TestBildOut.PNG', image)

ModuleNotFoundError: No module named 'cv2'

I was expecting that if opencv is working in the Virtual Environment, it would work too in the Notebook with the same Virtual Environment…

Is there a way to fix the Problem?