Filtering buildings out of LIDAR-data without LIDAR-Module

Hi!

Is it possible to filter LIDAR Points in the way, that only building-Points result? I have LIDAR-data in the Format LAS 1.3 with only points that are no ground (only buildings an some points of trees). When loading the data into Global Mapper i made the Setting, that only single-points are displayed, but now there are still single points in the trees but I only want to have points in the buildings.