undefined symbol: __atomic_fetch_add_8

Question

I'm trying to test my picamera on thonny python ide on my raspberry pi but i'm getting an error:

Traceback (most recent call last):
  File "/home/pi/Documents/Camera_test.py", line 2, in <module>
    import cv2
  File "/usr/lib/python3/dist-packages/thonny/backend.py", line 305, in _custom_import
    module = self._original_import(*args, **kw)
  File "/home/pi/.local/lib/python3.7/site-packages/cv2/__init__.py", line 3, in <module>
    from .cv2 import *
  File "/usr/lib/python3/dist-packages/thonny/backend.py", line 305, in _custom_import
    module = self._original_import(*args, **kw)
ImportError: /home/pi/.local/lib/python3.7/site-packages/cv2/cv2.cpython-37m-arm-linux-gnueabihf.so: undefined symbol: __atomic_fetch_add_8

I've already tried searching for possible solutions but were not able to do it because i cant understand what they were trying to say something about -latomic. i'm pretty much new to this.

import numpy as np
import cv2

cap = cv2.VideoCapture(0)
cap.set(3,640) # set Width
cap.set(4,480) # set Height

while(True):
    ret, frame = cap.read()
    frame = cv2.flip(frame, -1) # Flip camera vertically
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)

    cv2.imshow('frame', frame)
    cv2.imshow('gray', gray)

    k = cv2.waitKey(30) & 0xff
    if k == 27: # press 'ESC' to quit
        break

cap.release()
cv2.destroyAllWindows()

For what it's worth I'm having the same problem when importing OpenCV on my Raspberry Pi Compute Module 3, so at least we're not alone. — Rob Smallshire, Nov 09 '19 at 20:51
The thing is it works on the terminal, but not on thonny ide. — , Nov 10 '19 at 01:37
The workaround for this OpenCV problem is to set the LD_PRELOAD environment variable (this is not the same as a variable in Python) to cause the missing library to be loaded: LD_PRELOAD=/usr/lib/arm-linux-gnueabihf/libatomic.so.1 Unfortunately, I couldn't find a way to set environment variables in the Thonny IDE. — Rob Smallshire, Nov 10 '19 at 12:12
I recommend you follow this GitHub issue on the PiWheels OpenCV build. Hopefully a fixed version of the OpenCV wheel will be forthcoming soon. https://github.com/piwheels/packages/issues/59 — Rob Smallshire, Nov 10 '19 at 12:14

score 13 · Answer 1 · answered Dec 17 '19 at 19:05

13

Use OpenCV contrib with the right version.

pip install opencv-contrib-python==4.1.0.25

See answer at the end of this post.

answered Dec 17 '19 at 19:05

cristhoper

141
5

This worked for me on a RPi 4. I did not get a chance to try Ismael's answer. – Robert Bain Apr 30 '20 at 18:01
Unfortunately this didn't work on my RPi4, but luckily https://stackoverflow.com/a/60237868/4831224 worked. – alfred Jun 18 '20 at 06:52

laksh · Answer 2 · 2019-11-14T13:15:05.810

2

If you pip install opencv then try
in your virtual environment

"pip install opencv-contrib-python==3.4.3.18"

edited Nov 14 '19 at 13:15

answered Nov 14 '19 at 12:39

laksh

21
3

Ismael Nabil · Answer 3 · 2019-11-15T07:01:36.060

I was facing the same problem also while folowing this totorial https://www.pyimagesearch.com/2019/09/16/install-opencv-4-on-raspberry-pi-4-and-raspbian-buster/

in comments is solved in this link and also solve the same for me thanks to him :- https://www.pyimagesearch.com/2019/09/16/install-opencv-4-on-raspberry-pi-4-and-raspbian-buster/#comment-572080

and this is what he wrots:-

#

I’m following the tutorial with RP4, 1gb memory, on Buster.

I was seeing the following error after following step 4(a), the full compile, when verifying the cv2 install from Python console (step 5):

ImportError: /home/pi/.virtualenvs/cv/lib/python3.7/site-packages/cv2/cv2.cpython-37m-arm-linux-gnueabihf.so: undefined symbol: __atomic_fetch_add_8

I was able to resolve the issue with the following steps:

1 – $ sudo find / -type f -name ‘atom.so*’ /usr/lib/arm-linux-gnueabihf/libatomic.so.1.2.0

2 – LD_PRELOAD=/usr/lib/arm-linux-gnueabihf/libatomic.so.1.2.0 python3

3 – Python 3.7.3 (default, Apr 3 2019, 05:39:12) [GCC 8.2.0] on linux Type “help”, “copyright”, “credits” or “license” for more information.

import cv2 print(cv2.version) 4.1.1

Hope this helps anyone with the same issue…

J

#

Also for ur information when i follow another tuotrail for the same writer it was working ok with me without problems here is the link:-

https://www.pyimagesearch.com/2018/09/26/install-opencv-4-on-your-raspberry-pi/

I am still 15 days experience in python and raspberry pi so sorry for any mistake in advane regards

score 0 · Answer 4 · answered Nov 19 '20 at 03:10

Follow these steps it worked fine for me:

Install OpenCV on Raspberry Pi

sudo apt-get update
sudo apt-get install libhdf5-dev -y && sudo apt-get install libhdf5-serial-dev -y && sudo apt-get install libatlas-base-dev -y && sudo apt-get install libjasper-dev -y && sudo apt-get install libqtgui4 -y && sudo apt-get install libqt4-test -y
pip3 install --user opencv-contrib-python
pip install opencv-python

Testing OpenCV

To check whether OpenCV is correctly installed or not, try importing OpenCV by typing: Run python shell python3

then type: import cv2

If no errors are shown, your installation was successful!

To know which version of OpenCV you have, type the following command: cv2.version

Recommended Optional Libraries

sudo apt install libatlas3-base sudo apt-get install python3-numpy

sudo apt update sudo apt-get install python3-matplotlib -y

undefined symbol: __atomic_fetch_add_8

4 Answers4

Install OpenCV on Raspberry Pi

Testing OpenCV

Recommended Optional Libraries

Linked