to_png_with_metadata.py

def to_png_with_metadata(img, path, **meta_kwds):
    """Write a PIL image to PNG with associated metadata.

    Parameters
    ----------
    img : PIL.Image.Image
        Image to write.
    path : str, pathlib.Path
        Save the image to this path. The extension '.png' is added
        if it is not present.
    **meta_kwds
        Key=value pairs to write to the PNG file.

    Returns
    -------
    None

    Example
    -------
    >>> import PIL.Image
    >>> to_png_with_metadata(image, "foo.png", name="bob")
    >>> saved_img = PIL.Image.open("foo.png")
    >>> saved_img.text
    {"name": "bob"}
    """
    from pathlib import Path
    from PIL.PngImagePlugin import PngInfo

    pnginfo = PngInfo()
    for key, value in meta_kwds.items():
        pnginfo.add_text(key, str(value))
    path = Path(path).with_suffix(".png")
    img.save(path, format="png", pnginfo=pnginfo)