Error in compiling specific Dlib program c++

I am trying to make a program for face recognition using dlib & opencv

Program for face detection is working correctly but when I copied the code in another program which is supposed to work on frame of camera instead of images I'm getting a error - see image for errordlibfacedetectError

code for program working correctly- [facedetectcorrectprogram][2] code for program with errors- https://pastebin.com/7EktwVfM

another problem -I have to compile program inside dlib's libray example folder for correct compilation else I get error see screenshot facedetectErrorOtherLocation
when I compile inside example folder program works correctlyenter image description here is this related to the cause of error?