The Radius Outlier filter passes data through the Point Cloud Library (PCL) RadiusOutlierRemoval algorithm.
RadiusOutlierRemoval filters points in a cloud based on the number of neighbors
they have. Iterates through the entire input once, and for each point, retrieves
the number of neighbors within a certain radius. The point will be considered an
outlier if it has too few neighbors, as determined by min_neighbors. The
radius can be changed using radius.