Small script that "flattens" transparent png files by setting the alpha layer to a color.

remove_png_alpha.py

from PIL import Image


class AmbiguousArgs(BaseException):
    pass


def remove_png_alpha(image_path, overwrite=False, color=(255, 255, 255), out_path=None):
    """
    Removes the alpha layer form an input png (probably works with other filetypes as well)
    """

    if out_path is None and overwrite is True:
        out_path = image_path
    elif overwrite is False and out_path is None:
        raise AmbiguousArgs("If overwrite is false, must input out_path argument!")

    with Image.open(image_path).convert("RGBA") as png:
        background = Image.new("RGBA", png.size, color)
        alpha_composite = Image.alpha_composite(background, png)
    alpha_composite.save(out_path)
    return alpha_composite