class_docstr: This class represents masks in the form of bitmaps.
  
  Args:
      masks (ndarray): ndarray of masks in shape (N, H, W), where N is
          the number of objects.
      height (int): height of masks
      width (int): width of masks
class_docstr_tok: ["This","class","represents","masks","in","the","form","of","bitmaps",".","Args",":","masks","(","ndarray",")",":","ndarray","of","masks","in","shape","(","N",",","H",",","W",")",",","where","N","is","the","number","of","objects",".","height","(","int",")",":","height","of","masks","width","(","int",")",":","width","of","masks"]
code: def __repr__(self):
      s = self.__class__.__name__ + "("
      s += f"num_masks={len(self.masks)}, "
      s += f"height={self.height}, "
      s += f"width={self.width})"
      return s
  
imports: from abc import ABCMeta, abstractmethod
  import cv2
  import mmcv
  import numpy
  import pycocotools.mask
  import torch
  from mmcv.ops.roi_align import roi_align
label_desc: Use image node_id 4 for calling the BitmapMasks obj's underlying member method code with example usage: obj.__repr__() and returns: s