pip install opencv-python
it says:
Successfully installed numpy and opencv-python
Good.
I then run .py:
import cv2
It says:
No module named ‘cv2’
What am I doing wrong?
2 Likes
What OS are you on?
If your on raspberryPiOS it may be you need to set up an environment where the modules can be sand-boxed for your code.
1 Like
Hey there, @Bill293536.
As Pixmusix said, it could be down to a Virtual Environment issue, but I’m curious what tutorial are you using?
Every tutorial I have seen on using opencv asks uses to manually download the opencv from github. I’ve never seen any guide recommend installing it via pip.
Pixmusic, Jane,
Thank you.
I will do core opencv again and see if that helps.
Bill
Pixmusic, Jane,
It works!
I now have a problem.
from picamera2 import Picamera2
No module named ‘libcamera._libcamera’
What do I do?
Easy fix, you just need to install it.
From context I think you are using Raspberry Pi Os.
I’ve learned that, as a rule of thumb, if the package has “lib” in the name it probably wants to be installed system wide. On Debian based systems, like RP Os, apt is right tool for this.
sudo apt install python3-libcamera
1 Like
Pixmusix,
I put the:
sudo apt install python3-libcamera
into the Terminal, and the last item is:
python3-libcamera set to manually installed
Is still fails of:
from picamzero import Camera
What should I do?
1 Like
Hey @Bill293536,
I noticed that your error message occured on a different import than previously. In your last post, you said:
But in this reply, you said the error is on:
- Have you changed anything else in the intervening time between your last post and now.
- Could you post a screenshot of the exact error message that you are receiving?
- Can I just confirm as well that when you did this command as in the tutorial:
echo '/usr/lib/python3/dist-packages' > /home/pi/miniforge3/envs/ultralytics-env/lib/python3.11/site-packages/system-packages.pth
That you replaced the ‘pi’ directory with the home directory that you’re using on the Pi.
Jane,
Thank you.
Right,
ra5@ra5:~ $ sudo apt install python3-libcamera
The result was:
…python3-libcamera set to manually installed
What should I do?
My .py (Python) was:
from picamzero import Camera
Shell:
…
from ._libcamera import *
ModuleNotFoundError: No module named ‘libcamera._libcamera’
What should I do?
Bill
1 Like
pi → ra5
1 Like
Hey there, Bill,
Are you sure that it’s meant to be:
from picamzero import Camera
If you’re using this guide then the module is listed as picamerazero2 and the import command is:
from picamera2 import Picamera2
1 Like
Jane,
Thank you.
Uniformity, both give the same result!
ModuleNotFoundError: No module named ‘libcamera._libcamera’
Both:
from picamzero import Camera
and
from picamera2 import Picamera2
What do you think I should do?
Bill
Hi Bill,
Lets take a step back and make sure all the pieces are in the right place.
The following command will check to see if the _libcamera module is on your system:
dpkg -L python3-libcamera | grep _libcamera
If this returns nothing then -libcamera is not properly installed on your system, in which case you should try installing python3-libcamera again.
Another common cause of this is having your code and modules be on different sides of a virtual environment. The following terminal commands will run a quick test to see if this works from a command line:
python3 -c "import libcamera; print('libcamera ok')"
python3 -c "from picamzero import Camera; print('picamzero ok')"
if everything is set up correctly, these commands should both work without errors from inside of your virtual environment.
Let us know how this goes!
Hi Samuel,
I had tried the commands you listed.
The first one listed the .libcam
The second and the third listed:
No module named: libcam
(ultralytics-env) ra5@ra5
What should I do?
Bill
python3 -c "import libcamera; print('libcamera ok')"
python3 -c "from picamzero import Camera; print('picamzero ok')"
Both give:
ModuleNotFoundError: No module named ‘libcamera._libcamera’
What should I do?
1 Like
…
Thonny→Run→Configure interpreter→
Python executable:
/home/ra5/miniforge3/envs/ultralytics-env/bin/python
1 Like
Hey @Bill293536 ,
Thanks for checking that! It seems like you may have a few conflicting versions of libcamera floating around on your system.
Your system-wide install of libcamera seems to be there based on the result of the first command, which should include _libcamera. The result you get from the following commands is only a module not found error, which indicates that you also have another libcamera version (likely installed using the PIP method), which doesn’t have the correct module for your use case.
The best way to get around all this would be to start from the beginning with a fresh install. Would it be possible for you to reimage your Pi’s SD card so that we can be sure you don’t have any unexpected libcamera installations floating around?
1 Like
“The best way to get around all this would be to start from the beginning with a fresh install. Would it be possible for you to reimage your Pi’s SD card so that we can be sure you don’t have any unexpected libcamera installations floating around?”
Very, very carefully…
I still have:
picamera2/libcamera
ModuleNotFoundError: No module named ‘libcamera._libcamera”
Oh dear!
What can I do?
1 Like
What happens when you try installing the below?
sudo apt install -y python3-libcamera
Looks like Raspberry Pi Org have there own code base for python implementations of libcamera.
Maybe that’s what python is looking for? 
1 Like
