OpenCV not working properly with python on Linux with anaconda. Getting error that cv2.imshow() is not implemented

Question

This is the exact error that I am getting. My OS is Ubuntu 16.10.

OpenCV Error: Unspecified error (The function is not implemented. Rebuild the library with

Answer 1

For me (Arch Linux, Anaconda with Python 3.6), installing from the suggested channels menpo or loopbio did not change anything. My solution (see related question) was to

1. install pkg-config (sudo pacman -Syu pkg-config),
2. remove opencv from the environment (conda remove opencv) and
3. re-install opencv from the conda-forge channel (conda install -c conda-forge opencv)

conda list now returns opencv 3.3.0 py36_blas_openblas_203 [blas_openblas] conda-forgeand all windows launched using cv2 are working fine.

Answer 2

1.The easiest way:

conda remove opencv
conda update conda
conda install --channel menpo opencv

or (for OpenCV 3.1) :

conda install -c menpo opencv3

2.And if u don't want to do this, you can try to use matplotlib .

import cv2
import matplotlib.pyplot as plt

img = cv2.imread('img.jpg',0)

plt.imshow(img, cmap='gray')
plt.show()

3.Or try to build library by your own with option WITH_GTK=ON , or smth like that.

Update - 18th Jun 2019

I got this error on my Ubuntu(18.04.1 LTS) system for openCV 3.4.2, as the method call to cv2.imshow was failing. I am using anaconda. Just the below 2 steps helped me resolve:

conda remove opencv
conda install -c conda-forge opencv=4.1.0

If you are using pip, you can try

pip install opencv-contrib-python

Answer 3

For my system (Ubuntu 18.04) the following was working.
First:

sudo apt-get update -y

sudo apt-get install -y libgtk2.0-dev

conda create -n py35 python=3.5

conda activate py35

Then configure the environment

pip install Cython

pip install scikit-build

conda install -c anaconda cmake

pip install dlib

pip install face_recognition

pip install imutils

And finally:

pip install opencv-contrib-python

Answer 4

I used pip to install opencv-python. (https://pypi.org/project/opencv-python/)

1) Remove the opencv package from conda:

>> conda remove opencv

2) To your env.yml file add this:

...
dependencies:
  - numpy
  - pytest
  ...
  - pip:
    - opencv-python

Answer 5

Remove opencv from anaconda=

conda remove opencv

Then, reinstall opencv using pip:

pip install opencv

This is working for me.

Answer 6

Easy with Ubuntu 18.04. It works for me:

Remove opencv-python:

pip3 uninstall opencv-python

And then re-install opencv-python:

pip3 install opencv-python

Issue was resolved.