opencv cv2.destroyAllWindows() doesnt respond

Question

I have 64bit, ubuntu system. Im running the code in idel. I was facing opencv hang issue , the image shows up but I have to force kill the image window. So reffered to this thread -- Using other keys for the waitKey() function of opencv

import cv2
img = cv2.imread('sof.jpg') # load a dummy image
while(1):
    cv2.imshow('img',img)
    k = cv2.waitKey(3000) & 0xff
    if k==32:    # SpaceBar key to stop
        break
    elif k==-1:  # normally -1 returned,so don't print it
        continue
    else:
        print k # else print its value

Still its not working image hangs and I have to close it manually.

Your code works fine for me. Can you try it from the command line shell instead of from idle? I had problems with idle and GUIs (I think it was tkinter) a long time ago. — KobeJohn, Mar 27 '14 at 08:46

score 0 · Answer 1 · answered Mar 27 '14 at 08:12

0

try :

k = cv2.waitKey(3000) & 0xff

answered Mar 27 '14 at 08:12

berak

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Can u explain a bit ? – Abhishek Bansal Mar 27 '14 at 08:15
mask out the 'ascii' part from whatever you get there (scankeys?) , so you can check against k==27 or similar – berak Mar 27 '14 at 08:19
Its not working. I had to again restart the idle shell to kill the image – Mar 27 '14 at 08:21

R K Bhalodia · Answer 2 · 2017-12-06T15:43:17.550

Add cv2.waitkey(0) and cv2.destroyallwindows() but If you have used python notebooks then there is a problem in Unix based system to run a program of opencv. It will cause system freeze so you will need to restart kernel everytime when you try to execute code.

I have an alternative method which would prevent from freezing your system

Steps:

-Copy the code from python notebooks and create new filename.py and paste it
- Open terminal
- cd path/to/file
- source activate VirtualEnvironment
- python filename.py

This will run code directly from terminal. Hope this helps you. Example Link: https://youtu.be/8O-FW4Wm10s

opencv cv2.destroyAllWindows() doesnt respond

2 Answers2