How do I paste multiple images onto one image and output multiple other images?

Question

I am busy writing something to manipulate a image and paste other images onto it.

I am trying to change the background and the hat on a dog to various others and output multiple files with randomly generated images. The input images come from folders ( backgrounds and hats ). As we take pictures and copy them into the folder called background, I want to be able to run my Python script to change the background of the dog by picking a random image from the backgrounds folder. I want to be able to do the same with images in the hats folder. Will add more folders over time, but that's another day's question.

So far, I am able to paste items onto the main image. I have multiple PNG files in the folders and I get three images out, but all three images are the same. My code only seems to load one background and one hat.

Please help on how I can paste random images from the two folders onto my main image of the dog. Dog stays static, but backgrounds and hats will change. The options should be as many as the combinations can allow. So three folders with three options each will have alot of combination options. I have set the limit to three, but each time the images should render different combinations.

My code so far:

import glob
from PIL import Image

def main():

    q = 0
    hat_image = glob.glob("hats/*.png")
    for image in hat_image:
        with open(image, 'rb') as file:
            hat = Image.open(file)

    bg_image = glob.glob("backgrounds/*.png")
    for image in bg_image:
        with open(image, 'rb') as file:
            bg = Image.open(file)

    try:
        while q < 3:
            img = Image.open("base.png")
            img.paste(hat, (276, 176), hat)
            # mouth = Image.open("./mouth/mouth1.png")
            img.paste(bg, (226,476), bg)
            img.save("final{}.png".format(q), "PNG")
            q += 1

    except IOError:
        pass

if __name__ == "__main__":
    main()

Answer 1

If you want to have all possible combinations of background and hat images, you simply need to iterate accordingly, ie using nested for loops:

import glob

from PIL import Image

bg_filenames = glob.glob('backgrounds/*.png')
hat_filenames = glob.glob('hats/*.png')
dog_image = Image.open('dog.png')

for bg_filename in bg_filenames:
    for hat_filename in hat_filenames:
        output_image = Image.open(bg_filename)
        output_image.paste(dog_image)
        output_image.paste(Image.open(hat_filename))
        output_image.save('output/{}_{}.png'.format(
            bg_filename.split('\\')[1].split('.png')[0],
            hat_filename.split('\\')[1].split('.png')[0]
        ))

print(glob.glob('output/*.png'))
# ['output\\alley_baseball.png',
#  'output\\alley_cowboy.png',
#  'output\\alley_fedora.png',
#  'output\\garden_baseball.png',
#  'output\\garden_cowboy.png',
#  'output\\garden_fedora.png',
#  'output\\park_baseball.png',
#  'output\\park_cowboy.png',
#  'output\\park_fedora.png']

If you actually want a single image per execution with randomly chosen background and hat, simply use randint w.r.t. the amount of background and hat images:

import glob

from PIL import Image
from random import randint

bg_filenames = glob.glob('backgrounds/*.png')
hat_filenames = glob.glob('hats/*.png')
dog_image = Image.open('dog.png')

bg_filename = bg_filenames[randint(0, len(bg_filenames)-1)]
hat_filename = hat_filenames[randint(0, len(hat_filenames)-1)]

output_image = Image.open(bg_filename)
output_image.paste(dog_image)
output_image.paste(Image.open(hat_filename))
output_image.save('output/{}_{}.png'.format(
    bg_filename.split('\\')[1].split('.png')[0],
    hat_filename.split('\\')[1].split('.png')[0]
))

print(glob.glob('output/*.png'))
# ['output\\alley_cowboy.png',
#  'output\\garden_baseball.png',
#  'output\\garden_fedora.png']                 After three runs

For both versions, you can easily add more folders like shoes or gloves or whatever.

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System information
----------------------------------------
Platform:      Windows-10-10.0.19042-SP0
Python:        3.9.6
PyCharm:       2021.2
Pillow:        8.3.1
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