Function convert_to_bytes

DemoPrograms/Demo_Image_Viewer_Thumbnails.py:37–67

Will convert into bytes and optionally resize an image that is a file or a base64 bytes object. Turns into PNG format in the process so that can be displayed by tkinter :param file_or_bytes: either a string filename or a bytes base64 image object :type file_or_bytes: (Union[str, b

(file_or_bytes, resize=None, fill=False)

def convert_to_bytes(file_or_bytes, resize=None, fill=False):
    '''
    Will convert into bytes and optionally resize an image that is a file or a base64 bytes object.
    Turns into  PNG format in the process so that can be displayed by tkinter
    :param file_or_bytes: either a string filename or a bytes base64 image object
    :type file_or_bytes:  (Union[str, bytes])
    :param resize:  optional new size
    :type resize: (Tuple[int, int] or None)
    :return: (bytes) a byte-string object
    :rtype: (bytes)
    '''
    if isinstance(file_or_bytes, str):
        img = PIL.Image.open(file_or_bytes)
    else:
        try:
            img = PIL.Image.open(io.BytesIO(base64.b64decode(file_or_bytes)))
        except Exception as e:
            dataBytesIO = io.BytesIO(file_or_bytes)
            img = PIL.Image.open(dataBytesIO)

    cur_width, cur_height = img.size
    if resize:
        new_width, new_height = resize
        scale = min(new_height / cur_height, new_width / cur_width)
        img = img.resize((int(cur_width * scale), int(cur_height * scale)), PIL.Image.LANCZOS)
    if fill:
        img = make_square(img, THUMBNAIL_SIZE[0])
    with io.BytesIO() as bio:
        img.save(bio, format="PNG")
        del img
        return bio.getvalue()