How to augment training data 'on the fly' with multiclass segmentation

I am trying to follow through this code sample: https://keras.io/examples/vision/deeplabv3_plus/

The author is not augmenting the data in anyway. The dataset used here (CIHP) has training, validation and test images and both training and validation have corresponding masks for the objects of interest.

How can we run augmentations on the data during training?

computervision data segmentation training training data