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namedWindow fails to display graphics if minimised immediately on creation

asked 2017-02-19 11:17:32 -0500

JimboStlawrence gravatar image

Since upgrading to OpenCV 3.2 from 2.4.3 (I believe it was around that), a window created using OpenCV fails to display any graphics if minimised immediately after creation, even if it is brought back up. The standard white cross still appears in the window as the mouse is moved across it, but no graphics can be displayed. If the window is left alone after creation and the first graphics are drawn, all is well; the window can be minimised, graphics drawn etc. and the window brought back up without issue.

Not sure where/how to report this issue.

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First try to reproduce on a small example : everybody would be able to reproduce error.

Second record your screen and share video

LBerger gravatar imageLBerger ( 2017-02-19 13:44:34 -0500 )edit

os ? gui toolkit used ?

berak gravatar imageberak ( 2017-02-20 03:18:32 -0500 )edit

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answered 2017-02-24 15:40:02 -0500

JimboStlawrence gravatar image

Hi, it'd take me forever to redo something like that from scratch i.e. a 'small example'.

I use Visual Studio 2015 / Windows 10.

I fixed the issue, well not exactly a fix, but I simply do an "cv::imshow("drawing", img);" of the Mat immediately after creating the window. The user therefore doesn't have time to minimise it before it's had its first image...



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sorry, but i cannot reproduce it.

please again, add the code you were using originally to your question

berak gravatar imageberak ( 2017-02-25 03:37:31 -0500 )edit

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Asked: 2017-02-19 11:17:32 -0500

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Last updated: Feb 24 '17