code: def polarToLinear(img, shape=None, center=None, maps=None,
                    interpolation=cv2.INTER_AREA,
                    borderValue=0, borderMode=cv2.BORDER_REFLECT, **opts):
      '''
      map a 2d polar (r, phi) polar array to a  Cartesian (x,y) array
      using opencv.remap
      '''
  
      if maps is None:
          mapY, mapX = polarToLinearMaps(img.shape[:2], shape, center)
      else:
          mapY, mapX = maps
  
      o = {'interpolation': interpolation,
           'borderValue': borderValue,
           'borderMode': borderMode}
      o.update(opts)
  
      return cv2.remap(img, mapY, mapX, **of polarToLinear(img, shape=None, center=None, maps=None,
                    interpolation=cv2.INTER_AREA,
                    borderValue=0, borderMode=cv2.BORDER_REFLECT, **opts):
      '''
      map a 2d polar (r, phi) polar array to a  Cartesian (x,y) array
      using opencv.remap
      '''
  
      if maps is None:
          mapY, mapX = polarToLinearMaps(img.shape[:2], shape, center)
      else:
          mapY, mapX = maps
  
      o = {'interpolation': interpolation,
           'borderValue': borderValue,
           'borderMode': borderMode}
      o.update(opts)
  
      return cv2.remap(img, mapY, mapX, **o)
docs: map a 2d polar (r, phi) polar array to a  Cartesian (x,y) array
      using opencv.remap