INTERPRETABILITY OF GEOGRAPHIC INFORMATION FROM HIGH RESOLUTION SATELLITE IMAGES
Toshiaki Hashimoto
CEReS(Center for Environmental Remote Sensing), Chiba University
Japan
E-mail: hashi@rsirc.cr.chiba-u.ac.jp
Commission II, Working Group 1
KEYWORDS: Interpretability, High resolution images, Geographic information
ABSTRACT
One of the trends of sensor development is the improvement of spatial resolution. It will be expected that more information will be
extracted from the images of higher resolution. In this study, the interpretability of geographic information from high resolution images
are examined. The examination was performed using simulation images generated from aerial photos. Some conditions of real satellite
images like spatial resolution, atmospheric effects, dynamic range, etc. are taken into consideration in the generation of simulation
images. The geographic information to be interpreted are those containing in the existing topographic or thematic maps such as roads,
railways, buildings, water bodies, forests, etc. Through the examination, it was expected that most of geographic information could be
extracted from the images of the same resolution as ALOS satellite or better.
1. INTRODUCTION
This study was conducted on the following background.
(1) The launch of ADEOS/AVNIR, the plan of ALOS/PRISM
[RESTEC, 1995], AVNIR-2 and the development of
commercial high resolution satellites.
(2) The needs of revising technique of GIS data in proper cost.
The object of this study is to evaluate what kinds of geographic
information can be interpreted from high resolution satellite data.
2. METHODOLOGY
2.1 Test Area
Two kinds of test areas were selected in Japan. One contains
urban areas, agricultural areas, forest areas. Another contains
mountainous regions.
2.2 Simulated Images
Figure 1 shows the procedure for the generation of simulated
images.
(1) The simulated images were generated from color air photos of
1/10,000. The photos were digitized into 1 meter resolution.
(2) To consider the atmospheric effects, the digitized images were
blurred by the Point Spread Function with clear atmosphere
[Kawata, 1997].
(3) The spatial resolutions of simulated images were determined
under the assumption that ALOS, ADEOS/ AVNIR and
commercial satellites would be utilized.
(4) The dynamic range of digitized images were different from
that of real satellite images. The former was adjusted to the
dynamic range of ADEOS/AVNIR images.
(5) The high-resolution data will be compressed onboard for
downlinking and decompressed on the ground. The same
process was adopted for the simulation.
(6) The Pa/Mu composite, or the Pan-sharpened image, were used
for interpretation to take both advantages of the high
resolution of panchromatic band and the spectral character
istics of multi-bands.
Figure 1 Procedure of simulation image generation
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