Opencv can't move thread to another one

[kiloa44]

The library has a problem in dealing with Qt objects when it tries to move from a thread to another, which causes a crash with an exit code (139).
here is the code which fails at cv2.imshow('frame',gray):

import numpy as np
import cv2
cap = cv2.VideoCapture(0)
while(True):
# Capture frame-by-frame
ret, frame = cap.read()
# Our operations on the frame come here
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
# Display the resulting frame
cv2.imshow('frame',gray)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
# When everything done, release the capture
cap.release()
cv2.destroyAllWindows()

and this is the output of the code:

QObject::moveToThread: Current thread (0x19a67b0) is not the object's thread (0x1a497b0).
Cannot move to target thread (0x19a67b0)

[skvark]

Duplicate of #46. This will not be fixed because the error is caused by conflicting Qt installations.