Parsing the output of onnx YOLOv3 model

[pasmai]

I do not understand how the output is parsed from the onnx model.

I have set-up a Unity project similar to this that uses YOLOv5m as its model and the output does not make sense. I would like to understand how this repository has achieved the transformation of the output layers into something useable.

Can anybody provide some insight?
Thanks