def changeGroupImageRemote(self, image_url, thread_id=None):
        """
        Changes a thread image from a URL

        :param image_url: URL of an image to upload and change
        :param thread_id: User/Group ID to change image. See :ref:`intro_threads`
        :raises: FBchatException if request failed
        """
        (image_id, mimetype), = self._upload(get_files_from_urls([image_url]))
        return self._changeGroupImage(image_id, thread_id)