Method getBlurredImageUsingIntegralImage

common/src/range_image.cpp:916–959

////////////////////////////////////////////////////////////////////

/////////////////////////////////////////////////////////////////////////
void
RangeImage::getBlurredImageUsingIntegralImage (int blur_radius, float* integral_image, int* valid_points_num_image,
                                               RangeImage& blurred_image) const
{
  this->copyTo(blurred_image);
  for (int y=0; y<static_cast<int>(height); ++y)
  {
    for (int x=0; x<static_cast<int>(width); ++x)
    {
      const PointWithRange& old_point = getPoint (x, y);
      PointWithRange& new_point = blurred_image.getPoint (x, y);
      if (!std::isfinite (old_point.range))
        continue;
      
      int top= (std::max) (-1, y-blur_radius-1), right = (std::min) (static_cast<int> (width)-1, x+blur_radius), bottom =
          (std::min) (static_cast<int> (height)-1, y+blur_radius), left= (std::max) (-1, x-blur_radius-1);
      
      float top_left_value=0, top_right_value=0,
            bottom_right_value=integral_image[bottom*width+right], bottom_left_value=0;
      int top_left_valid_points=0, top_right_valid_points=0,
          bottom_right_valid_points=valid_points_num_image[bottom*width+right], bottom_left_valid_points=0;
      if (left>=0)
      {
        bottom_left_value = integral_image[bottom*width+left];
        bottom_left_valid_points = valid_points_num_image[bottom*width+left];
        if (top>=0)
        {
          top_left_value = integral_image[top*width+left];
          top_left_valid_points = valid_points_num_image[top*width+left];
        }
      }
      if (top>=0)
      {
        top_right_value = integral_image[top*width+right];
        top_right_valid_points = valid_points_num_image[top*width+right];
      }
      int valid_points_num = bottom_right_valid_points + top_left_valid_points - bottom_left_valid_points -
                             top_right_valid_points;
      new_point.range = (bottom_right_value + top_left_value - bottom_left_value - top_right_value) / 
                        static_cast<float> (valid_points_num);
    }
  }
  blurred_image.recalculate3DPointPositions ();
}

/////////////////////////////////////////////////////////////////////////
void