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FAST RECONSTRUCTION OF THREE DIMENSIONAL CITY MODEL 
BASED ON AIRBORNE LIDAR 
H. Lin *, H.T. Jing, L.P. Zhang 
School of geodesy and geomatics of XuZhou Normal University, XuZhou, 221116, PR China. 
Commission I, WG 1/2 
KEY WORDS: Airborne LIDAR, Three Dimensional City Model (3DCM), 3D Data Acquisition, Digital Surface Model(DSM), 
Point Cloud, Data Classification and Extraction 
ABSTRACT: 
Three Dimensional City Model (3DCM) research becomes a hot area in GIS field in recent years. The 3DCM research also has great 
significance in traffic, land, mine, surveying and mapping, and other fields, especially in urban plan. The difficulty of acquiring 3D 
data is the key hamper for the development of 3DCM. Airborne LIDAR, which integrates GPS, INS and scanning laser rangefinder, 
can rapidly acquire the 3D position of ground using airplane. It is very economical, efficient and convenient to acquire 3D data. 
Traditional three-dimensional data acquisition method can’t satisfied with the more and more fast development need of the 
city .airborne LIDAR technology is regarded as a convenience, swift, high-efficient three-dimensional data acquisition method, 
widely admitted progressively. LIDAR technology already has a history of more than ten years, major problem of hardware 
technology and system integration has already solved, had already developed successfully many business soft systems. But post 
processing technology of LIDAR data still lag behind after practice, among them, the key problem is the data classification and 
extraction. A lot of commercial companies and some large institute are devoted to the research of this respect in the world, many 
kinds of filtration algorithm and extraction method have been introduced .in the fixture, more effective and more perfect algorithm 
will been used. Because of the complexity of the topography and surface feature of the objective world, at present, the research on 
data classification and extraction lay particular emphasis on different applications. As regards modeling of three-dimensional city, 
study mainly concentrate on the topography extraction and the building extraction etc. This paper has introduce post-processing 
procedure of airborne LIDAR data systematically, has realized the fast reconstruction of three-dimension urban model based on 
LIDAR data, enable this technology to serve the information construction of the city better. 
1. INTRODUCTION 
The construction of city informationization is gradually 
developing towards depth and width by the impetus of the 
national informationization tide. As an important technical 
support of the construction, GIS technology has already 
developed from two-dimension to three-dimension step by step. 
Three-dimension GIS can provide richer spatial information for 
city, give a more real expression of the objective world, enable 
the users to carry out browse, analysis and decision-making 
under the spatial and the three-dimension environment. Three- 
dimension city model is the foundation of establishing three- 
dimensional GIS, however ,for a long time, owing to the 
acquisition problem of three-dimension data, three-dimensional 
city model is difficult to establish fast and update timely, which 
impedes three-dimensional GIS’s further development. The 
traditional methods of acquiring three-dimensional data include 
the topographic map with the architectural design blueprint, 
aerial photogrammetry, close-range photogrammetry, field 
surveying and etc, each of which has its own characteristics, but 
all have following limitation: complicated data acquisition 
procedure, long cycle, low efficiency and high cost. And worse 
still, regarding the complex building, the data acquisition is of 
low precision, and reconstruction model may be seriously 
distorted, such as Shanghai symbolic building -the oriental 
Pearl and Jinmao mansion. 
* E-mail:linhuixznu@126.com ; Phone:13852002411 ; 
In recent years, airborne LIDAR is gradually regarded as a new 
technology to acquire the three-dimension data precisely and 
fast. LIDAR is the initial letter abbreviation of Light Detection 
And Ranging ( sometimes translated into laser radar),which is 
one kind of space surveying system integrating many advanced 
technologies such as laser ranging, digital aerial 
photogrammetry, global positioning system(GPS) and inertial 
navigation system(INS). Its operation principle is to use high 
speed laser scanning survey to obtain fast three-dimension 
coordinate of the measured object surface in a large area with 
high resolution, subsequently, three-dimension data information 
of city may be collected quickly and massively .Compared with 
the traditional surveying methods, the airborne LIDAR 
technology has the following characteristics: high efficiency, 
high precision, automation, lower cost and rich information etc. 
1) high efficiency: the airborne LIDAR can survey 1000 square 
kilometers within 12 hours, with the help of relevant software, 
the post-processing of LIDAR data may be conducted 
automatically or semi-automatically, transforming the LIDAR 
point cloud data into GIS or data formats received in other 
fields. 
2) high precision: because laser pulse is not easily influenced by 
shadow and solar angle, the quality of acquired data is greatly 
improved, and especially the precision of elevation data is not 
limited by flight height. The precision of plane may reach 0.15 
to 1.0 meter and the precision of elevation may reach 10