new_contents: from __future__ import print_function, division
  import numpy as np
  
  import imgaug as ia
  import imgaug.augmenters as iaa
  from imgaug.augmentables.polys import Polygon, PolygonsOnImage
  
  
  def main():
      nb_checked = 0
  
      augs = iaa.SomeOf((1, None), [
          iaa.Resize({"height": (1, 100), "width": (1, 100)}),
          iaa.Affine(
              scale=(0.01, 2.0),
              rotate=(-360, 360),
              shear=(-360, 360),
              translate_px={"x": (-50, 50), "y": (-50, 50)}
          ),
          iaa.PerspectiveTransform((0.01, 0.2))
      ])
  
      height, width = 100, 200
  
      while True:
          poly = create_random_polygon(height, width, nb_checked)
          psoi = PolygonsOnImage([poly], shape=(height, width, 3))
          psoi_aug = augs.augment_polygons(psoi)
  
          if not poly.is_valid or not psoi_aug.polygons[0].is_valid:
              print("poly:     ", poly, poly.is_valid)
              print("poly_aug: ", psoi_aug.polygons[0], psoi_aug.polygons[0].is_valid)
  
          assert poly.is_valid
          assert psoi_aug.polygons[0].is_valid
  
          nb_checked += 1
          if nb_checked % 100 == 0:
              print("Checked %d..." % (nb_checked,))
          if nb_checked > 100000:
              break
  
  
  def create_random_polygon(height, width, seed):
      rs = np.random.RandomState(seed)
      nb_points = rs.randint(3, 50)
      coords = rs.rand(nb_points, 2)
      coords = (coords * 2 - 0.5)  # allow coords outside of the image plane
      coords[:, 0] *= width
      coords[:, 1] *= height
      poly = Polygon(coords)
      if poly.is_valid:
          return poly
  
      new_seed = rs.randint(ia.SEED_MIN_VALUE, ia.SEED_MAX_VALUE)
      return create_random_polygon(height, width, new_seed)
  
  
  if __name__ == "__main__":
      main()
  
subject: Add check script for polygon validity during aug