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What happens during the execution of cvWaitKey()? What are some typical use cases? I saw it in OpenCV reference but the documentation isn't clear on its exact purpose.
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Python OpenCV – waitKey() Function waitkey() function of Python OpenCV allows users to display a window for given milliseconds or until any key is pressed. It takes time in milliseconds as a parameter and waits for the given time to destroy the window, if 0 is passed in the argument it waits till any key is pressed.
cv2. waitkey(1) waits for 1 ms and returns the code of the key on keyboard if it is pressed.
4. cv2. waitKey() This function is very important, without this function cv2.
Answer #1: 0xFF is a hexadecimal constant which is 11111111 in binary. By using bitwise AND ( & ) with this constant, it leaves only the last 8 bits of the original (in this case, whatever cv2. waitKey(0) is). Answered By: Kevin W.
cvWaitKey(x) / cv::waitKey(x) does two things:
cv::imshow()). Note that it does not listen on stdin for console input. If a key was pressed during that time, it returns the key's ASCII code. Otherwise, it returns -1. (If x is zero, it waits indefinitely for the key press.)cv::namedWindow(), or showing images with cv::imshow().A common mistake for opencv newcomers is to call cv::imshow() in a loop through video frames, without following up each draw with cv::waitKey(30). In this case, nothing appears on screen, because highgui is never given time to process the draw requests from cv::imshow().
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