code: def interest_points(
      f,
      nr_octaves=4,
      nr_scales=6,
      initial_step_size=1,
      threshold=0.1,
      max_points=None,
      is_integral=False,
  ):
      """
      desc_array = interest_points(f, nr_octaves=4, nr_scales=6, initial_step_size=1, threshold=0.1, max_points={all}, is_integral=False)
  
      SURF Detector
  
      Parameters
      ----------
      f : ndarray
          input image or integral image (if `is_integral`)
      nr_octaves : integer, optional
          Nr of octaves (default: 4)
      nr_scales : integer, optional
          Nr of scales (default: 6)
      initial_step_size : integer, optional
          Initial step size in pixels (default: 1)
      threshold : float, optional
          Threshold of the strength of the interest point (default: 0.1)
      max_points : integer, optional
          Maximum number of points to return. By default, return all.
      is_integral : boolean, optional
          Whether `f` is an integral image
  
      Returns
      -------
      points : ndarray of double, shape = (N, 5)
          `N` is nr of points. Each point is represented as
          *(y,x,scale,score,laplacian)* where *y,x,scale* is
          the position, *score* and *laplacian* the score and sign of the
          detector.
  
      See Also
      --------
      surf : SURF detection and descriptors
      descriptors : SURF descriptors
      """
      if not is_integral:
          f = integral(f)
      else:
          if f.dtype != np.double:
              raise TypeError(
                  "mahotas.surf: integral image must be of dtype double"
              )
      if max_points is None:
          max_points = -1
      return _surf.interest_points(
          f,
          nr_octaves,
          nr_scales,
          initial_step_size,
          threshold,
          max_points,
      )
  
file_path: mahotas/mahotas/features/surf.py
imports: from __future__ import division
  import numpy
  from .None import _surf
label_desc: Use image node_id 3 for calling a global function with example usage: interest_points(f, nr_octaves, nr_scales, initial_step_size, threshold, max_points, is_integral) and returns: _surf