Tflite modelmaker object detection: normalizing bounding box values

I am new to TF lite object detection and have gone through the tutorial:

and I think I understand it reasonably well. However, I notice that the bounding box is somehow normalised.

So, when I have my own dataset, each row looks like so (only 1 class:

``
TRAIN,/path/to/data//images/0.jpg,ONE_CLASS_CAT,270.5,115.10000000000036,787.3000000000011,483.3000000000011,


How does one normalise these coordinates values for tflite input?

Thank you!