undefined reference to `cv::VideoCapture::VideoCapture(int)’
找到cmark编译opencv的输出文件夹，我的是buildQT在.pro文件夹后添加： LIBS += D:\qt_opencv_config\opencv3.4.0\buildQT\bin\libopencv_shape340.dll LIBS += D:\qt_opencv_config\opencv3.4.0\buildQT\bin\libopencv_videoio340.dll
