How to send video from AGX ORIN detectNet.cpp to GTK3 window

How do I send video output from C++ version of detectnet.cpp to a window existing in GTK3. detectnet created/maintaind by dusty-nv provided for jetson-inference Hello World documentation. GTK3 is a C version UI building application from the Genome Tool Kit. I’m thinking I need shared memory where I can read the video output from a process running the C++ detectnet.cpp program. I will have a MIPI CSI camera as the source. I’m trying to avoid using GTK+ as it would be a complete new tool to learn…

Any hints, suggestions? Do or don’t do it this way?
Thanks, Steven