Find (and potentially eliminate 😈) semi-transparent pixels in a bunch of PNG files

find_semitrasparent_pixels.py

from PIL import Image
import os


FOLDER_PATH = "output3"

for filename in os.listdir(FOLDER_PATH):
    img = Image.open(os.path.join(FOLDER_PATH, filename), 'r')
    has_alpha = (img.mode == 'RGBA')
    print(f"Handling {filename}...")
    if not has_alpha:
        print(f"Image {filename} has no alpha channel!")
        continue

    # red, green, blue, alpha = img.split()
    alpha = img.split()[-1]

    if not all((pixel == 0 or pixel == 255) for pixel in alpha.getdata()):
        # I know it iterates two times if any semi-transparent pixel is found,
        # but the goal is to get rid of them, so this code is a bit faster
        pixels = list(alpha.getdata())
        width, height = alpha.size
        for y in range(height):
            for x in range(width):
                if pixels[y * width + x] not in (0, 255):
                    print(f'Found semitrasparent pixel in "{filename}": ({y}, {x})')