points_foerstner算子提取关键点有两步，第一步和传统的foerstner算法一样，可是第二步中 ”把提取到的感兴趣点分成连接点和面积点，用两个优化函数平均点到边界的距离“ 这是什么意思呢？
points_foerstner算子：mvtec.com/doc/halcon/13/en/points_foerstner.html
原文：
In the second step, two optimization functions are calculated for the resulting points. Essentially, these optimization functions average for each point the distances to the edge directions (for junction points) and the gradient directions (for area points) within an observation window around the point. If Smoothing is 'gauss', the averaging is performed by a Gaussian of size SigmaPoints, if Smoothing is 'mean', the averaging is performed by a SigmaPoints x SigmaPoints mean filter. The local minima of the optimization functions determine the extracted points. Their subpixel precise position is returned in (RowJunctions, ColumnJunctions) and (RowArea, ColumnArea).
