Include path (Visual studio)

• Project-> Properties

• Configuration Properties -> C/C++ -> General -> Additional Include Directories

• 於下圖紅框處加入

    $(SolutionDir)External_lib\include
    $(SolutionDir)External_lib\include\opencv
    $(SolutionDir)External_lib\include\opencv2
    $(SolutionDir)為在電腦中資料夾的位置