Python Opencv imshow error

Question

my code:

import cv2
img = cv2.imread("dU4fHDw-Ho.jpg", cv2.IMREAD_GRAYSCALE)

cv2.imshow('image', img)
k = cv2.waitKey(0)
if k == 27:
    cv2.destroyWindow()

And i get this error:

OpenCV Error: Unspecified error (The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Carbon support. If you are on Ubuntu or Debian, install libgtk2.0-dev and pkg-config, then re-run cmake or configure script) in cvShowImage, file /io/opencv/modules/highgui/src/window.cpp, line 583
Traceback (most recent call last):
  File "simpleopencv.py", line 4, in <module>
    cv2.imshow('image', img)
cv2.error: /io/opencv/modules/highgui/src/window.cpp:583: error: (-2) The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Carbon support. If you are on Ubuntu or Debian, install libgtk2.0-dev and pkg-config, then re-run cmake or configure script in function cvShowImage

I'm using linux mint KDE What might be the problem?

Update1: Opencv works fine with python2.7 but not working for python3.5

Update2: As it turns out running the script as Jack Gold suggested actually worked but since i already had cv2 folder in my /usr/local/lib/python3.5/dist-packages/ (which was installed using PIP i think) conflicted with the one install using the script and python3 kept using the PIP version so, I deleted that cv2 folder and restarted and everything worked fine.

You're missing some libraries, please refer to my answer here - stackoverflow.com/a/44263478/7220609 — Jack Gold
– Jack Gold, Commented Jun 8, 2017 at 11:11

Anurag Kumar · Accepted Answer · 2017-08-13 09:16:15Z

2

Nothing to worry buddy,I suffered the same and this is how I got rid of this error, see if you have installed opencv via pip or pip3 or apt-get, first you gotta uninstall it

sudo pip3 uninstall (what you wrote while installing)

or sudo pip uninstall (what you wrote while installing)

or sudo apt-get remove (what you wrote while installing)

and afterwards build the opencv package from source code from github.

git clone https://github.com/opencv/opencv.git

cd ~/opencv

mkdir release

cd release

cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local ..

make

sudo make install

This will solve the problem. All the best.

answered Aug 13, 2017 at 9:16

Anurag Kumar

1,5031 gold badge12 silver badges11 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Bubble Bubble Bubble Gut · Accepted Answer · 2017-06-08 13:33:01Z

0

Not sure about the problem since it works fine for me. But just as an alternative, use plt.imshow() from Matplotlib, it also works fine.

answered Jun 8, 2017 at 13:33

Bubble Bubble Bubble Gut

3,37617 silver badges30 bronze badges

4 Comments

Unique Kiddo Over a year ago

just tried, but matplotlib's image is quite different than opencv's(using python 2.7). It's displaying grayscale image but matplotlibs's image looks green

Bubble Bubble Bubble Gut Over a year ago

plt.imshow() also accepts another parameter "cmap", try plt.imshow(img, cmap="gray") to show image in gray scale

Unique Kiddo Over a year ago

does that means I don't have to pass cv2.IMREAD_GRAYSCALE in cv2.imread() ?

Bubble Bubble Bubble Gut Over a year ago

Yes, it can take an array of shape (n, m, 3) and show it in gray scale.

Shawn Mathew · Accepted Answer · 2017-06-08 19:02:46Z

0

Did you install OpenCV using pip? If you did, note that as mentioned here, this is the unofficial package for OpenCV and does not have support for GUI windows (cv2.imshow(), etc)

I would recommend using Anaconda to install opencv using conda install -c conda-forge opencv=3.2.0 or conda install -c menpo opencv3=3.2.0

answered Jun 8, 2017 at 19:02

Shawn Mathew

2,3371 gold badge17 silver badges33 bronze badges

Comments

Casper · Accepted Answer · 2017-08-16 03:22:49Z

0

Easier solution is provided by conda

conda install -c loopbio -c conda-forge -c pkgw-forge ffmpeg-feature ffmpeg gtk2 opencv

You may see the following error after conda install

Traceback (most recent call last):
    File "./test.py", line 21, in <module>
      import cv2
ImportError: libopenblas.so.0: cannot open shared object file: No such file or directory

Just install openblas library would solve

yum install openblas-devel -y

Reference

[sdvillal | github] https://github.com/conda-forge/opencv-feedstock/issues/43

answered Aug 16, 2017 at 3:22

Casper

1494 bronze badges

Comments

Watercayman · Accepted Answer · 2019-12-29 17:08:34Z

0

You should use absolute path to read your image.

For me on Mac OS:

img = cv2.imread('/Users/nicholasleung/Documents/after effect/AL.png')

edited Dec 29, 2019 at 17:08

Watercayman

8,17810 gold badges35 silver badges50 bronze badges

answered Dec 29, 2019 at 17:01

myworldbox

4211 gold badge8 silver badges13 bronze badges

Collectives™ on Stack Overflow

Python Opencv imshow error

5 Answers 5

Comments

4 Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

5 Answers 5

Comments

4 Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related