script.py

import PIL
from PIL import Image
import os
import subprocess as sub

coef = 0.45
waifu2xCaffeExe = 'C:\\Programmes\\waifu2x-caffe\\waifu2x-caffe-cui.exe'
picFolder = os.getcwd()
waifuOption = '-m noise_scale -s 4 -n 3 -p cudnn -q 100'

fileList = os.listdir()
for file in fileList:
    if( ".jpg" in file):
        print(file)
        img = Image.open(file)
        size = int((float(img.size[0]) * coef)),int((float(img.size[1]) * coef))
        img = img.resize(size, PIL.Image.ANTIALIAS)
        img.save('smaller-'+file,quality=100)
        print("waifu2x-caffe-cui.exe -i "+picFolder+"\\smaller-"+file + " -o "+picFolder+"\\waifu2x-"+file + " " + waifuOption)
        sub.check_call(waifu2xCaffeExe
                       + " -i "+picFolder+"\\smaller-"+file
                       + " -o "+picFolder+"\\waifu2x-"+file
                       + " " + waifuOption
                       , shell=True)