[Python] cv2.destroyWindow does not work (Bug #2911)

On Ubuntu 12.10 using either the shipped OpenCV 2.3.1 or OpenCV 2.4.2 of the upcoming Ubuntu 13.04, one cannot close named windows as expected using cv2.destroyWindow.

See for example on StackOverflow:

• http://stackoverflow.com/questions/6116564
• http://stackoverflow.com/questions/11593046

Although both questions use OpenCV 1.x, the same problem occurs using the cv2 import of OpenCV 2.x

The only way to really close a window is to call the functions in this particular order:

cv2.destroyWindow(name)
cv2.waitKey(-1)
cv2.imshow(name, img)

where img is an arbitrary numpy array.

For the sake of completeness:

% LC_ALL=C apt-cache policy python-opencv
python-opencv:
  Installed: 2.4.2+dfsg-0exp2ubuntu1
  Candidate: 2.4.2+dfsg-0exp2ubuntu1
  Version table:
 *** 2.4.2+dfsg-0exp2ubuntu1 0
        100 /var/lib/dpkg/status
     2.3.1-11ubuntu2 0
        500 http://de.archive.ubuntu.com/ubuntu/ quantal/universe amd64 Packages