From: Antonio Ospite <ao2@ao2.it>
Date: Thu, 22 Feb 2018 11:56:50 +0000 (+0100)
Subject: opencv_trail_effect.cpp: use cv::waitKeyEx() instead of cv::waitKey()
X-Git-Url: https://git.ao2.it/experiments/opencv_trail_effect.git/commitdiff_plain/1fb92e6c58573d8188e8fe2cd49257409d15f527?ds=sidebyside

opencv_trail_effect.cpp: use cv::waitKeyEx() instead of cv::waitKey()

In some OpenCV 3 version there was a change of behavior of cv::waitKey()
in case the delay expired with no key presses, use cv::waitKeyEx() to
rely on the old behavior.

For details see
https://github.com/opencv/opencv/pull/7866#issuecomment-269322846
---

diff --git a/opencv_trail_effect.cpp b/opencv_trail_effect.cpp
index 97b4aa7..5a4e928 100644
--- a/opencv_trail_effect.cpp
+++ b/opencv_trail_effect.cpp
@@ -204,7 +204,7 @@ int main(int argc, char *argv[])
 		trail->draw(canvas);
 
 		cv::imshow("Frame", canvas);
-		if (cv::waitKey(30) >= 0)
+		if (cv::waitKeyEx(30) >= 0)
 			break;
 
 		if (outputVideo.isOpened())