无法在 openCV 中显示图像显示 windows

Question

I am using openCV python bindings. I am trying to show the output image using the following listing:

cv.NamedWindow('display')
cv.MoveWindow('display', 10, 10)
cv.ShowImage('display', cvImage)

But I do not see any window.

My platform is Linux (openSuse 11.4), python-opencv version 2.1 and python 2.7.

Answer 1

You need to call the WaitKey function to process the events. Check out the documentation: http://opencv.willowgarage.com/documentation/python/highgui_user_interface.html#waitkey

This function is the only method in HighGUI that can fetch and handle events, so it needs to be called periodically for normal event processing, unless HighGUI is used within some environment that takes care of event processing.

Just add a WaitKey(0) at the end of your code and it should work just fine.

Answer 2

in addition to this information: WaitKey(1) does not wait for 1ms but for at least 15ms...you can measure that if you want.