joining images вертикально

import numpy as np
from PIL import Image

import os


# РАБОТАЕТ !!!!!!!!!
os.chdir(r'path to ya folder')


list_im = [file for file in os.listdir()]
imgs    = [ Image.open(i) for i in list_im ]
# pick the image which is the smallest, and resize the others to match it (can be arbitrary image shape here)
min_shape = sorted( [(np.sum(i.size), i.size ) for i in imgs])[0][1]
imgs_comb = np.hstack( (np.asarray( i.resize(min_shape) ) for i in imgs ) )

# save that beautiful picture
imgs_comb = Image.fromarray( imgs_comb)
imgs_comb.save( 'testttttttt.jpg' )    

# for a vertical stacking it is simple: use vstack
imgs_comb = np.vstack( (np.asarray( i.resize(min_shape) ) for i in imgs ) )
imgs_comb = Image.fromarray( imgs_comb)
imgs_comb.save( os.path.join( os.getcwd(), 'testt final.jpg') )

Взял отсюда: https://stackoverflow.com/questions/30227466/combine-several-images-horizontally-with-python