Gets a centered square crop of all images that is inside a directory and resize all of them to a size with a specific side and outputs them to another directory.

square_and_shrink.py

from PIL import Image
import os
import numpy as np

def _square(img):
	w, h = img.size
	s = min(h, w)
	sh = (h - s)/2.0
	sw = (w - s)/2.0
	cropped_img = img.crop((sw, sh, sw+s, sh+s))
	return cropped_img

def _shrink(cropped_img, side):
	return cropped_img.resize((side, side), resample=Image.LANCZOS)

def square_and_shrink(side, input_dir, output_dir):
	for f in os.listdir(input_dir):
		img = Image.open(input_dir + f)
		cropped_img = _square(img)
		resized_img = _shrink(cropped_img, side)
		resized_img.save(output_dir + f)

square_and_shrink(256, 'images/', 'squared_and_shrinked/')