04
RAPIDLY FLOOD EXTENT MAPPING SERVER DESIGN AND EXPERIMENT USING
MATHEMATICAL MORPHOLOGY RECOGNITION AND COOPERATED DISASTER
INFORMATION SERVERS ON THE INTERNET
Yasuharu YAMADA*, Tawatchai Tingsanchali**, Virat Khao-Uppatum***, Chatchom Chompradist***
*Japan International Research Center for Agricultural Sciences(JIRCAS), Owashil-1, Tsukuba, Ibaraki, 305-8686 JAPAN, -
yamaday(àjircas.affrc.go.jp
**Professor of Water Resources Engineering, School of Civil Engineering, Asian Institute of Technology(AIT), Paholyothin Highway,
Km.42, P.O.Box 4, Klong Luang, Pathumthani 12120 Thailand, - tawatch(@ait.ac.th
***Office of Hydrology and Water Management, Royal Irrigation Department(RID), Samsen Road Dusit Bangkok 10300 Thailand, -
(viratk, ccchom)@mail.rid.go.th
Commission VII, WG5
KEY WORDS: Flood, Mathematical morphology, SAR, ALOS, Thailand, Terrain feature recognition
ABSTRACT:
Mathematical morphology operations and directional filters provide image feature measurements. Terrain feature recognition for SAR
imagery combines both target's physical property and morphological image processing. This method should be adopted in order to
solve the problem how to distinguish paddy fields from flood inundated areas by using the conventional SAR signal intensity change
method. For example, if the Levee of paddy fields is above the inundated water surface, the paddy fields should be almost without
damages in the consolidated farm lands. If the region of the low backscattering intensity level occupy large area, that can be most likely
large water surface, flood-inundated areas. These calculations require only a snapshot of SAR image. This image processing procedure
will have advantage over the flood disaster monitoring using SAR satellite data. The authors plan to make rapidly flood extent mapping
server on the Internet for the early warning system of regional and agricultural flood damage. The analyzed satellite images showing
flood extent superimposed on a geographic global map should be converted to an appropriative format image and stored into image
database. The authors installed web server such as windows2000 server IIS, the ColdFusionMX as a web application server and the
MapGuide server as a web map generator, the ImageWebServer as a swiftly showing tool bridged from the image database and the
MapGuide server. The users of such web map only should prepare a web browser. They can see the flood extent image and global maps
in the same browser. The SAR data should be the useful tool for risk management as monitoring change or disaster in the first situation.
Recently, as web mapping standard is preparing, distributed map server design and its experiment is planning among JIRCAS, AIT and
PDC.
1. INTRODUCTION production. The water level usually rises several centimeters
There are many kinds of agricultural disaster, such as per day during flood in such areas. Then satellite SAR, which
cool summer damage of paddy rice crop, drought damage, recurrent time is rather long period, can detect flood extent.
flood damage, etc. In the big river downstream regions of Addition to that, the next Japanese satellite, ALOS has
tropical areas, flood is not unusual thing. But the life style PALSAR sensor and one of the mission of ALOS is the
among the people living in such regions and the way of rice disaster monitoring.
crop production was changed. (Farmers cultivate less floating Natural disaster can happen anywhere on the earth, but
rice.) The flood influences both their daily life and rice crop the organizations, which can analyze satellite data, will be
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