C++ waitKey (30) 在 OpenCV 中是什么意思？
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what does waitKey (30) mean in OpenCV?
提问by Imbarfar
Possible Duplicate:
OpenCV - cvWaitKey( )
可能重复：
OpenCV - cvWaitKey()
I want to filter the video frame.
我想过滤视频帧。
for(;;)
{
cap.read( frame);
medianBlur(frame,framedst,5);
imshow("frame",frame);
imshow("framedst",framedst);
if( waitKey (30) >= 0) break;
}
What does the waitKey(30)mean? Because if I comment out the line if( waitKey (30) >= 0) break;, the above code doesn't work!
这是什么waitKey(30)意思？因为如果我注释掉那行if( waitKey (30) >= 0) break;，上面的代码就行不通了！
采纳答案by tito
The function waitKey()waits for a key event for a "delay" (here, 30 milliseconds). As explained in the OpenCV documentation, HighGui (imshow()is a function of HighGui) need a call of waitKey regularly, in order to process its event loop.
该函数waitKey()等待按键事件的“延迟”（此处为 30 毫秒）。正如OpenCV 文档中所解释的，HighGui（imshow()是HighGui的一个函数）需要定期调用 waitKey，以处理其事件循环。
Ie, if you don't call waitKey, HighGui cannot process windows events like redraw, resizing, input event, etc. So just call it, even with a 1ms delay :)
即，如果您不调用 waitKey，HighGui 无法处理窗口事件，如重绘、调整大小、输入事件等。所以只需调用它，即使延迟 1 毫秒 :)
