ISPRS, Vol.34, Part 2W2, “Dynamic and Multi-Dimensional GIS”, Bangkok, May 23-25, 2001
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3D SPATIAL OBJECTS MODELING AND VISUALIZATION BASED ON LASER LANGE DATA
Jie DU 1 , Apisit EIUMNOH 1 , Xiaoyang CHEN 2 , Michiro KUSANAGI 2
Natural Resources Management,
Rural Development, Gender and Resources Program,
Asian Institute of Technology,
P.O. box 4, Klong Lung, Pathumthani, 12120, Thailand
Space Technology Application and Research Program,
Asian Institute of Technology,
P.O. box 4, Klong Lung, Pathumthani, 12120, Thailand
KEYWORDS: 3D spatial data, visualization, laser range-scanning data, DEM, DSM
ABSTRACT
The laser technology has been currently brought into photogrammetry and cartography fields as a tool for mapping. The main application
of laser scanning systems concerns large-scale and precise topographic DEMs. Automatically interpret range images for extracting geo
spatial features and reconstruction of geo-objects are the main research problems. The objective of this paper is to develop the
algorithms and methods for modeling and visualization of 3D spatial data in large scale based by processing laser-scanning data. For
processing airborne laser range data, a set of algorithms should be developed. Those algorithms are mainly include: TIN based range
image interpolation, MM (Mathematical Morphology) based range image filtering, features extraction and range image segmentation,
feature generalization and optimization, 3D objects reconstruction and modeling, CG (Computer Graphic) based visualization and
animation of virtual environment.
1 Introduction
Over the past few years, the need for describing larger scale
3D spatial data is continually increasing. These data are used
for variety of applications such as region planing, architecture,
archaeology, disaster prevention, microclimate investigations or
transmitter placement in telecommunication. Many kinds of
raster and vector based models for describing, modeling, and
visualizing 3D spatial data in large scale have been developed.
With the development of laser technology and sensor
techniques, several kinds of airborne laser scanners are
available for acquisition of high accuracy 3-D spatial data in
real or very fast time. The main application of laser scanning
systems concerns large-scale and precise topographic DEMs,
especially in areas that are difficult for conventional
photogrammetry. These are forest areas of total or scattered
coverage. As a side product tree heights are obtained. Other
interesting applications concern coastal areas, wetland,
beaches, dunes etc. As in all successful developments, new
applications emerge which had not been anticipated at the
beginning.
The purpose of this research is to study and develop the
algorithms and methods for modeling 3D spatial objects based
on airborne laser range data. For processing airborne laser
range data, a set of algorithms should be developed. Those
algorithms are mainly include TIN based range image
interpolation, MM based range image filtering, features
extraction and range image segmentation, feature
generalization and optimization, 3D object reconstruction and
modeling, CG based visualization and animation of virtual
environment. In this research we using laser scanning data of
Kyoto Station area simulate 3D reconstruct result.
2 Methodology
The airborne laser scanner reaches area coverage, for
instance, by an oscillating deflection of the laser beam
perpendicular to the flight direction. The instant angle of
deflection has to be known precisely, as the basic geometric
principle is maintained of providing position, direction and
length of the vector to the ground point, for each shot.
An essential feature of laser scanning is the potentials for
almost complete automation, the GPS, INS and laser data
being digitally recorded. After the GPS processing and the
necessary system calibration the computation of the terrain
points, the interpolation of a DEM and the block formation of
the DEM is quite straightforward, as far as open terrain is
concerned.
It includes following main problems:
• Pre-processing for inputting airborne Laser range
data
• Semi-automated extraction of 3D Spatial features
• Methods for 3D-visual modeling
• Generation of virtual reality environments
• Editing & Checking methods
Figurel Integration of laser range images and existing maps
Figure2 3D object reconstruction based on laser range images