def METHOD_NAME(self, ann_path):
    """
    Load basic information of dataset such as image path, label and so on.
    :param ann_path: coco json file path
    :return: image info:
    [{'file_name': '000000000139.jpg',
      'height': 426,
      'width': 640,
      'id': 139},
     ...
    ]
    """
    coco_dict = self.xml_to_coco(ann_path)
    self.coco_api = CocoXML(coco_dict)
    self.cat_ids = sorted(self.coco_api.getCatIds())
    self.cat2label = {cat_id: i for i, cat_id in enumerate(self.cat_ids)}
    self.cats = self.coco_api.loadCats(self.cat_ids)
    self.img_ids = sorted(self.coco_api.imgs.keys())
    img_info = self.coco_api.loadImgs(self.img_ids)
    return img_info