def init_app(self, app):
        """Flask application initialization."""
        self.init_config(app)
        self.iiif_ext = IIIF(app=app)
        self.iiif_ext.api_decorator_handler(protect_api)
        self.iiif_ext.uuid_to_image_opener_handler(image_opener)
        app.extensions['invenio-iiif'] = self