def METHOD_NAME(anno_file):
    """
    get_size_ratios
    :param anno_file: coco anno flile
    :return: size_ratio: (box_long_size / pic_long_size)
    """
    coco_dict = json.load(open(anno_file))
    image_list = coco_dict['images']
    anno_list = coco_dict['annotations']
    image_id2hw = {}
    for im_dict in image_list:
        im_id = im_dict['id']
        h, w = im_dict['height'], im_dict['width']
        image_id2hw[im_id] = (h, w)
    box_ratios = []
    for a_dict in anno_list:
        im_id = a_dict['image_id']
        im_h, im_w = image_id2hw[im_id]
        bbox = a_dict['bbox']
        x1, y1, w, h = bbox
        pic_long = max(im_h, im_w)
        box_long = max(w, h)
        box_ratios.append(box_long / pic_long)
    return np.array(box_ratios)