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fbmfbm
23rd February 2009, 16:08
Hi all,

Sorry for this newbee question but i 'don't find answer on doc or forum for this.....


In an application with Qt4.43 on window, i would like to display alternate QPicture in a QLabel and capture picture of this screen (projected with display projector) with webcam.

I have made all the sys and i have a little probleme of synchronisation with capture and display in the QLabel : How to be certain that the QLabel display the new QPicture before i capture img with webcam ????

I would like to find some signal or listener in QLabel to wait for end of updating process.....but don't find any one....

So, my capture whase some time more rapidly process than the refresh in QLabel....

Did someone know some way to track the enf of QLabel/Qpicture display process, before i can grabe the frame with webcam.

Did i use an other tread...but how to wait end of refresh process to proced cap ..????


thank's for your help.

user_mail07
24th February 2009, 00:54
You can have timer. Use timeout() signal when picture will be set. U can check whether picture has been set on the QLabel by calling picture() m/d of QLabel.

fbmfbm
24th February 2009, 11:10
Thank's for your answer.

I'm lookink for sort of listener about QPicture...but don't find any.....what do you means about pictur() m/d ...??? sorry it's certanely a dummy ask....