Display error while debugging remotely an OpenCV code

I am trying to use DS-5 debugger to debug remotely an OpenCV code, that simply reads and displays an image. The target platform is Hardkernel ODROID-XU4 SBC running on Ubuntu 18.04, and the host is a Windows 7 host PC. Everything works just fine and I can debug and step into different regions in my program, however, when I try to display the image in my PC, I get the error depicted in the following debug log

Preparing the debug session

# cd "/home/bin"
# gdbserver :5000 "./opencv_cross_tutorial" 
Process ./opencv_cross_tutorial created; pid = 2362
Listening on port 5000
Debug session has been started, connecting to gdbserver
Remote debugging from host
Unable to init server: Could not connect: Connection refused

(Display window:2362): Gtk-WARNING **: 16:50:47.229: cannot open display: 

Child exited with status 1

I would like to know, how can I resolve this display error and display the image on my host PC, and how can I export the display to the ODROID since it is connected to an LCD screen ? 

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