In [10]:

    

import numpy as np
import PIL
from PIL import Image

list_im = [
#     './output_images/test1.png'
#           ,'./output_images/sobelTH-test1.png'
          './output_images/fs.png'
          , './output_images/cc.png'
          ]
imgs    = [ PIL.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 = PIL.Image.fromarray( imgs_comb)
# imgs_comb.save( './output_images/cc.png' )    

# 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 = PIL.Image.fromarray( imgs_comb)
imgs_comb.save( './output_images/Lane_thresh.png' )