ISPRS Commission III, Vol.34, Part 3A „Photogrammetric Computer Vision“, Graz, 2002
SURFACE MODELLING OF URBAN 3D OBJECTS FROM
VEHICLE-BORNE LASER RANGE DATA
Huijing Zhao, Ryosuke Shibasaki
University of Tokyo
Commission III, WG III/7
KEY WORDS: Laser Range Scanner, Vehicle-borne, Marching Cube, Urban 3D Model, Reconstruction
ABSTRACT:
In this paper, a method is presented to generate surface model of urban out-door environment using vehicle-borne laser range
scanners, which have been developed in Konno ef al.[11]. A classification is conducted first, where range points are divided into the
groups of vertical building surface, road surface, other surface, window, tree and others, unknown objects. Erroneous measurement
are corrected, e.g. window data or discarded, e.g. irregular data. Volumetric modelling and marching cube method are exploited in
this research to model both surface-structured objects, e.g. building and road surface, and volume-structured objects, e.g. tree.
Estimates for signed distance are proposed. Through an experiment, it is demonstrated that urban out-door environment can be
reconstructed with high automation and efficiency using our method.
1. INTRODUCTION
Up to now, many research groups in photogrammetry
community have been devoted to the analysis of aerial based
imageries for the reconstruction of 3D urban object (e.g. [5,10]).
Normally, aerial survey can cover relatively wide area, but fail
in capturing details of urban objects such as sidewall (facade) of
buildings. On the other hand, most of the existing systems in
computer vision field have been demonstrated at small scales,
using simple objects, under controlled light condition. (e.g.
[1,6,15]). With the development of automobile navigation
system, 3D GIS (Geographic Information System), and
applications using virtual and augmented reality, details of
urban out-door objects are found to be of importance, as user
viewpoints are involved on the ground, not in the air. An
efficient reconstruction method exploiting ground-based survey
technique at large scale, for complicated and unexpected object
geometries, under uncontrolled light condition is required.
Several systems aiming at generating 3D model of real world
have been developed during the last few years. According to the
major data source being used for reconstructing object geometry,
the systems can be broadly divided into two groups. One is
called image-based approach. Another is called range-based
approach.
In the first group, 3D model of urban scene is reconstructed
using still or moving images. Image-based approach is also
called in-direct approach since object geometry has to be
automatically or human-assistedly extracted using stereo or
motion techniques. Debevec, et al. [3] presented an interactive
method of modelling and rendering architectural scenes from
sparse sets of still photographs, where large architectural
environment can be modelled with far fewer photographs than
using other full-automated image-based approaches. MIT City
Scanning Project [9] developed a prototype system of
automatically reconstructing textured geometric CAD model of
urban environment using spherical mosaic images, where
camera's position and orientation of each spherical image is
first initialised using positioning sensors, then refined through
image matching. Geometric representation is extracted either
using feature correspondence or by identifying vertical facades.
Uehara and Zen [12] proposed a method of creating textured 3D
map from existing 2D map using motion technique, where a
video camera is mounted on a calibrated vehicle and the image
streams that captured are geo-referenced to the existing 2D map
using GPS data. Through the above research efforts, it is
demonstrated that image-based approach can be used in
reconstructing 3D model of urban out-door environment.
Whereas, the difficulties in reliable stereo matching, distortion
from limited resolution and unstable geometry of CCD cameras
are the major obstacles to reconstruct a 3D model of
complicated environment with necessary accuracy and
robustness.
In the second group, 3D model of urban scene is reconstructed
using range image. Range-based approach is also called direct
approach since object geometry can be directed measured using
range scanner. In recent years, as the development of laser
technique, range scanners using eye-safe laser with high
accuracy, large range distance and high measurement frequency
are being used for the modelling of urban environment.
Sequeira et al.[14] and El-Hakim et al.[4] developed systems
on reconstructing indoor environment of rather large scale.
Stamos and Allen [17], Zhao and Shibasaki [20] aimed at
generating 3D model of urban out-door objects. In these
systems, range scanners are mounted on stationary platforms
(called stationary system). Range images produced by the
systems are typically rectangular grids of range distances (or 3D
coordinates after conversion) from the sensor to the objects
being scanned. Objects are measured from a number of
viewpoints to reduce occlusions, where location and direction
of viewpoints are unknown or roughly obtained using GPS,
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