2. image_resize_resample.py to resize and resample the pictures in a file location. you can set specific size to resize the images i.e 128x128 or 512x512.
3. extract_face_image.py to extract the frontal face part of human face using haar cascade frontalface default . xml file.
you can see how haar cascade classifier works here : https://docs.opencv.org/3.4/db/d28/tutorial_cascade_classifier.html
Bye Bye.