The Cumulative Displacement Filter
Those interested in GPS, car navigation, geo-positionning and the like can check my paper about The Cumulative Displacement Filter, a new GPS position filtering algorithm for unaided GPS devices.
In this paper, I present a simple way to eliminate most of the residual noise in positions sent by typical GPS units, relying only on very basic mathematics such as averaging two-dimensionnal vectors.
It output smooth and evenly spaced positions, while removing part of the artifacts introduced by multipath, and thus is an ideal candidate filter for any road reduction filter.
A sample implementation is provided as well, that outputs KML-formatted data ready to be used with Google Earth.