Comparison of Filtering Algorithms

To determine the performance of filtering algorithms a study was conducted in which eight groups filtered data supplied to them. The study aimed to determine the general performance of filters, the influence of point resolution on filtering and future research directions. To meet the objectives the filtered data was compared against reference data that was generated manually. In general the filters performed well in landscapes of low complexity. However, complex landscapes as can be found in city areas and discontinuities in the bare earth still pose challenges. Comparison of filtering at lower resolutions confirms that amongst other factors the method of filtering also has an impact on the success of filtering and hence on the choice of scanning resolution. It is suggested that future research be directed at heuristic classification of point-clouds (based on external data), quality reporting, and improving the efficiency of filter strategies.