code: def fill_hole(input_mask):
      h, w = input_mask.shape
      canvas = np.zeros((h + 2, w + 2), np.uint8)
      canvas[1 : h + 1, 1 : w + 1] = input_mask.copy()
  
      mask = np.zeros((h + 4, w + 4), np.uint8)
  
      cv2.floodFill(canvas, mask, (0, 0), 1)
      canvas = canvas[1 : h + 1, 1 : w + 1].astype(np.bool_)
  
      return ~canvas | input_mask
  
file_path: PaddleOCR/ppocr/postprocess/fce_postprocess.py
imports: import cv2
  import paddle
  import numpy
  from numpy.fft import ifft
  from ppocr.utils.poly_nms import poly_nms, valid_boundary
label_desc: Use image node_id 1 for calling a global function with example usage: fill_hole(input_mask) and returns: unknown