A hybrid conditional random field for estimating the underlying ground surface from airborne LiDAR data

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

62 Scopus Citations
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Author(s)

  • Wei-Lwun Lu
  • Kevin P. Murphy
  • James J. Little
  • Alla Sheffer
  • Hongbo Fu

Related Research Unit(s)

Detail(s)

Original languageEnglish
Article number4909008
Pages (from-to)2913-2922
Journal / PublicationIEEE Transactions on Geoscience and Remote Sensing
Volume47
Issue number8
Publication statusPublished - Aug 2009

Abstract

Recent advances in airborne light detection and ranging (LiDAR) technology allow rapid and inexpensive generation of digital surface models (DSMs), 3-D point clouds of buildings, vegetations, cars, and natural terrain features over large regions. However, in many applications, such as flood modeling and landslide prediction, digital terrain models (DTMs), the topography of the bare-Earth surface, are needed. This paper introduces a novel machine learning approach to automatically extract DTMs from their corresponding DSMs. We first classify each point as being either ground or nonground, using supervised learning techniques applied to a variety of features. For the points which are classified as ground, we use the LiDAR measurements as an estimate of the surface height, but, for the nonground points, we have to interpolate between nearby values, which we do using a Gaussian random field. Since our model contains both discrete and continuous latent variables, and is a discriminative (rather than generative) probabilistic model, we call it a hybrid conditional random field. We show that a Maximum a Posteriori estimate of the surface height can be efficiently estimated by using a variant of the Expectation Maximization algorithm. Experiments demonstrate that the accuracy of this learning-based approach outperforms the previous best systems, based on manually tuned heuristics. © 2006 IEEE.

Research Area(s)

  • Conditional random fields (CRFs), Digital terrain model (DTM), Light detection and ranging (LiDAR) data filtering

Citation Format(s)

A hybrid conditional random field for estimating the underlying ground surface from airborne LiDAR data. / Lu, Wei-Lwun; Murphy, Kevin P.; Little, James J.; Sheffer, Alla; Fu, Hongbo.

In: IEEE Transactions on Geoscience and Remote Sensing, Vol. 47, No. 8, 4909008, 08.2009, p. 2913-2922.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review