Opencv removes the console window from

After opening an opencv project, on the project properties page, "configuration properties"/"linker"/"system" ("configuration properties"/"linkers"/"system ") in "subsystem", select "windows (/subsystem: Windows) as" Console (/subsystem: Console )"; If you only modify this item, the following error will be reported during re-Compilation:
Msvcrtd. Lib (crtexew. OBJ): Error lnk2019: external symbol that cannot be parsed _ winmain @ 16, which is referenced in function ___ tmaincrtstartup
You need to add the "entry point": maincrtstartup in the "advanced" option.

Compile again and then OK.

In addition, you can directlyProgramAdd the followingCode

// Hide the console window
# Pragma comment (linker, "/subsystem: \" WINDOWS \ "/entry: \" maincrtstartup \"")

You can hide the console window.