Cloudcompare & PCL matching point median (or standard deviation) distance suppression

One 、 brief introduction

During registration , After completing the matching of points （https://blog.csdn.net/dayuhaitang1/article/details/125934553?spm=1001.2014.3001.5501）, It is often necessary to further screen these matching points , Because some low-quality matching points not only affect the effect of registration , It will also increase the number of iterations , In many papers, in order to achieve better results , Often by setting the standard deviation or median of the distance between these matching points $3$