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APPLICATIONS OF SPOT-5 IMAGERY IN SURVEYING AND MAPPING OF WEST
REGIONS IN CHINA
HaiBin Ai a ’ b ’*, Jianqing Zhang 3 , Yanson Duan b , Yong Zhang 1
School of Remote Sensing and Information Engineering, Wuhan University, 430074 Wuhan, Hubei, China
b Supresoft Incorporation, 430079 Wuhan, Hubei, China -
ahb32@163.com
Commission WgS-PS: Working Group IV/9
KEY WORDS: Satellite Remote Sensing, Digital Maps, Digital Photogrammetry, Absolute Orientation, Topographic Mapping,
SPOT-5, Image Fusion
ABSTRACT:
During the past 50 years, there are no topographic maps at scaled of 1:50,000 in the West Regions of China. Beside the extremely
adverse environmental condition of the regions, the poor surveying and mapping technology is an important factor to cause the
situation. This kind of present condition limited the Development of the West Regions and embarrassed the economic and social
sustainable development of China. For solve this kind of predicament, the project of Surveying and Mapping of the West Regions in
China was launched in 2006 and Remote Sensing techniques are applied to the project. SPOT-5 imagery is one of important data
sources of the project. The paper discusses the applications of SPOT-5 images in Surveying and Mapping of West Regions in China.
Within the SPOT constellation, SPOT-5 is the most innovative satellite. SPOT-5 HRS, HRG and multi-spectral images are applied
in the project of Surveying and Mapping of West Regions in China. SPOT-5 images orientation is studied firstly. Secondly, mapping
from SPOT-5 HRS stereo image pairs in seamless mapping system is also given. Thirdly, DEM generation by two means are
introduced. Finally, DOM from SPOT-5 HRG and multispectral imageries are also introduced.
1. INTRODUCTION
During the past 50 years, there are no topographic maps at
scaled of 1:50,000 in the West Regions of China. Beside the
extremely adverse environmental condition of the regions, the
poor surveying and mapping technology is an important factor
to cause the situation. This kind of present conditions limited
the development of the west regions and embarrassed the
economic and social sustainable development of China. For
solving the kind of predicament, a national project of Surveying
and Mapping of the West Regions in China was launched in
2006 and Remote Sensing techniques are applied to the project.
To obtain stereoscopy with images from satellite scanners, two
solutions are possible (Toutin, 2001):
1. The in-track stereoscopy from the same orbit using fore
and aft images; and
2. The across-track stereoscopy from two different orbits.
The latter solution was more used since 1980: firstly, with
Landsat from two adjacent orbits (Simard,1983), then with
SPOT using across-track steering capabilities (Denis, 1986),
and finally with IRS-1 C/D by “rolling” the satellite (Gopala
Krishna et al., 1996). In the last few years the first solution got
renewed popularity with the JERS-l's Optical Sensor (OPS)
(Maruyama et al., 1994), the German Modular Opto-Electronic
Multi-Spectral Stereo Scanner (MOMS)(Ackerman et al., 1995;
Raggam et al., 1997; Komuset al., 1998), the Advanced
Spacebome Thermal Emission and Reflection Radiometer
(ASTER) (Tokunaga et al., 1996), the Indian Cartorsat-1, the
Taiwan Formosat-2, and most of the agile high-resolution
satellites (Toutin, 2004a).
Within the SPOT constellation, SPOT-5 is the most innovative
satellite. SPOT-5 was launched on 4th May, 2002 by
Arianespace from the Kourou Space Centre in French Guyana.
After completing two months of in-orbit tests it became fully
operational in July 2002. It comprises two identical optical
High Geometric Resolution (HRG) imaging instruments and the
High Resolution Stereoscopic (HRS) imaging instrument
(Bouillon et al., 2002), which enables both stereo solutions to
be performed and addressed. The HRG instruments offer an
oblique viewing capability and the viewing angle being
adjustable through ±27° relative to the vertical enables the
generation of across-track multi-date stereoscopy from two
different orbits. The base-to-height ratio (B/H) is thus between
0.6 and 1.1. On the other hand, the HRS instrument offers fore-
and-aft viewing capability for in-track stereoscopy from the
same orbit. The HRS instrument with a telescope viewing angle
of ±20° is dedicated for taking simultaneous stereo-pairs with
B/H of around 0.80. The stereo-pairs of 120km swath and
600km long (maximum length) are acquired in panchromatic
(black and white) mode with a sensor spatial resolution of 10m
but with 5m ground sampling distance (GSD) in the line
direction. Users could then apply traditional three-dimensional
(3D) photogrammetric techniques with the stereo-images to
extract accurate planimetric and elevation information and
collect cartographic maps. However, same-date in-track stereo
data acquisition gives a strong advantage to multi-date across-
track stereo-data acquisition because it reduces radiometric
image variations, and thus increases the correlation success rate
in any image matching process (Toutin, 2001) and reduces the
workload of tuning the tone of DOM. Moreover other payload
packages such as the same Vegetation instrument as on SPOT-4,
Email: ahb32@163.com Tel: 13607138724
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