Is there a faster alternative to PIL's Image.paste for multiple images?

Question

I am trying to use image.paste to paste many images onto one background.

My images contain their x,y offset values in their filenames (eg. Image_1000_2000.png is offset 1000,2000).

The code below works, but it's painfully slow. Here's what I've got:

import re
import glob
from PIL import Image

# Disable Decompression Bomb Protection
Image.MAX_IMAGE_PIXELS = None

# Set the dimensions of the blank canvas
newheight = 13000
newwidth = 13000

# Glob all the PNG images in the folder and create the blank canvas
photos = glob.glob("*.png")
blankbackground = Image.new('RGB', (newheight, newwidth), (0, 0, 0))
blankbackground.save(r'..\bg999.png', "PNG")

for photo in photos:
  blankbackground = Image.open(r'..\bg999.png')
  photog = Image.open(photo)

  # Get the x , y offsets from the filenames using re
  y_value = re.findall(r"0_(\d*).", photo)[0]
  y = int(y_value)
  x_value = re.findall(r'_(\d*).', photo)[0]
  x = int(x_value)

  # The actual paste operation, and save the image to be re-opened later
  blankbackground.paste(photog,(x,y))
  blankbackground.save(r"..\bg999.png")
  print(photo)

Any suggestions on a speedier alternative?

EDIT: As per the comments below, it is not necessary to save / reload the image with every photo. This makes it considerably faster.

Answer 1

As pointed out by Siyuan and Dan, Image.save does not require you to save the image and re-load it every loop.

Move the Image.open to before the loop, and move the Image.save to after the loop, as shown:

import re
import glob
from PIL import Image

# Disable Decompression Bomb Protection
Image.MAX_IMAGE_PIXELS = None

# Set the dimensions of the blank canvas
newheight = 13000
newwidth = 13000

# Glob all the PNG images in the folder and create the blank canvas
photos = glob.glob("*.png")
blankbackground = Image.new('RGB', (newheight, newwidth), (0, 0, 0))
blankbackground.save(r'..\bg999.png', "PNG")

# MOVE THE IMAGE.OPEN BEFORE THE LOOP
blankbackground = Image.open(r'..\bg999.png')
for photo in photos:
  photog = Image.open(photo)

  # Get the x , y offsets from the filenames using re
  y_value = re.findall(r"0_(\d*).", photo)[0]
  y = int(y_value)
  x_value = re.findall(r'_(\d*).', photo)[0]
  x = int(x_value)

  # The actual paste operation
  blankbackground.paste(photog,(x,y))
  print(photo)
# MOVE THE IMAGE.SAVE AFTER THE LOOP
blankbackground.save(r"..\bg999.png")

Thus, it goes from ten minutes to ten seconds.