merging.py

from PIL import Image
import os


# folder with the original image upscaled
imgUpscl_folder = "upscale/"
# folder with the alpha image upscaled
imgUpsclAlpha_folder = "upscale/alpha/"
# folder where the merged image is saved
imgMerging_folder = "upscale/alpha/merging/"
imgUpsclAlpha_name_extension = "_alpha"


# Create target Directory if don't exist for the merging folder
if not os.path.exists(imgMerging_folder):
    os.mkdir(imgMerging_folder)
    print("Directory " , imgMerging_folder ,  " Created ")
else:
    print("Directory " , imgMerging_folder ,  " already exists")


for element in os.listdir(imgUpsclAlpha_folder):
    if element.endswith(imgUpsclAlpha_name_extension + '.png'):

        alpha_channel = Image.open(imgUpsclAlpha_folder + element).convert('L')

        original_name = element.replace(imgUpsclAlpha_name_extension, '')

        image = Image.open(imgUpscl_folder + original_name).convert('RGBA')

        image.putalpha(alpha_channel)

        image.save(imgMerging_folder + original_name)