cv2.imshow() function is opening a window that always says not responding - python opencv

Question

I am trying to run a very simple program. To open and jpg file and display it using the opencv library for python. Initially it all worked fine but now it just opens a windo

Answer 1

None of the answers here worked in MacOS. The following works:

Just add a cv2.waitKey(1) after cv2.destroyAllWindows().

Example:

import cv2
image = cv2.imread('my_image.jpg')
cv2.imshow('HSV image', hsv_image); cv2.waitKey(0); cv2.destroyAllWindows(); cv2.waitKey(1)

Answer 2

I've been working with opencv 3.2 and matplotlib too recently and discovered (through trial and error of commenting out lines) that the import of pyplot from matplotlib has some sort of interference with the cv2.imshow() function. I'm not sure why or how it really works but in case anyone searches for this issue and comes across this old forum, this might help. I'm working to try to find a solution around this interference bu

Answer 3

The solution that worked for me: Switch from inline graphics to auto. It worked both in Spyder and in Jupyter notebooks.

• To change Spyder setting: Go to Tools > Preferences > IPhyton console > Graphics > Backend: Automatic (Change backend from Inline to Automatic)

• To change Notebook setting: Enter command:

  %matplotlib auto

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Some background for my case (for those who may be quick to judge):

It used to work fine: I could open an image, it would load, and it would be responsive (doesn't say "Not responding", can close, focus, etc.) Then I installed some packages and ran some demo notebooks that apparently messed up some settings (Spyder open files were reset too).

I tried adding waitKey(1) (and 0, 30, 1000, etc values too). It made the image load, at least. But the image frame was "Not Responding": didn't refresh, couldn't close, didn't come to top, etc. Had to close using cv2.destroyAllWindows().

Note that everything worked fine during the duration of waitKey. I put this in a loop that shows the same image in the same named window and waits for a few seconds. During the loop everything works fine. As soon as the loop ends, the image window is "Not responding" (which looks like a GUI thread issue). I tried using cv2.startWindowThread(), and didn't make any difference.

Finally, changing from Inline graphics to Auto brought everything back to order.