GIS SOLUTIONS FOR LOCAL GOVERNMENTS WITH IKONOS IMAGERY
M. Ozen”
* INTA SPACETURK, Haymana yolu 12.Km 06830 Gólbasi, Ankara, Turkey —
mozen@spaceturk.com.tr
+90.312.6122370/5105
PS WG IV/S
KEY WORDS: GIS, local governments, resolution, applications, municipality, spatial data, mapping.
ABSTRACT:
Geographic information play an important role in activities of local governments such as management of land and
water resources ,real estate transactions, land use development, city planning etc...So, state & local governments
are very important GIS users. For many GIS applications of local governments, one-meter resolution will be more
beneficial than other satellite imageries to acquire more detailed data. In addition, IKONOS' ability to acquire
either 11*11 km images or bigger scenes in one pass allows municipalities to quickly and inexpensively update part
or all their base map to follow up developments and changes. These advantages make IKONOS satellite imagery a
data source rather than a product.
1. INTRODUCTION
Improvements in information technology have provided
lots of opportunities to support data analyses. %80 of data
acquired from survey is related with geography. So, GIS
has a big portion in information systems. GIS is an
organized collection of computer hardware, software,
geographic data and personnel, designed to efficiently
capture, store, update, manipulate, analyze and display all
geospatial information.
Nearly every GIS user is a potential satellite imagery
customer but especially provincial and local governments,
utilities and telecommunications are three vertical markets
that recognize the unique advantages of high-resolution
satellite imagery such as having current, correct, faster
and objective data; used as a base map and a data source,
having a higher quality.
There are lots of advantages of IKONOS satellite imagery
like acquiring 11*11 km images or bigger scenes in one
pass that allows to get information through imageries
quickly and inexpensively. 1 meter spatial resolution and
ability to acquire stereo pair imageries are the other
advantages of IKONOS.
In GIS applications, the basic handicap is the lack of up-
to-date data. High resolution IKONOS images are the
basic source to get updated geographic data. Through
heads-up digitizing, vector base data can be generated
from the imagery. The vector data is not a map but it is
base vector data that is very useful in GIS applications.
2. AN EXAMPLE OF GIS SOLUTIONS FOR LOCAL
GOVERNMENTS BY USING IKONOS
The overall goal of the GIS Management projects has
been to maintain base data that includes updated features.
Updated IKONOS imagery is acquired to maintain these
base features. Local governments use accurate data as
base maps. To use IKONOS imageries efficiently, they
should have the same coordinate accuracy with base maps
using by government authorities. So, production of raster
data is the first step of the solutions with GIS applications
by IKONOS. First of all, Precision Plus imageries are
produced. After stereo image collection, ground control
points (GCP) are chosen (figure 2) over geo images.
Then, they are collected from survey and ingested to the
system (figure 3). By this process, precision stereo images
are produced. Over these precision stereo images, by tin
editing, Digital Elevation Model (figure 4) is produced
and with orthorectification process, precision plus images
are produced. (figure 5) Steps can be seen in figure 1.
Stereo Productio ; i
fa wn of Geo GCP wp § GCP
mage Image and Collection Ingest
Collection us
With Over Choosing :
75 Degree GCP
Production Production
of Precision PI TIN Productio N of
Stereo Editing n of ITM Precision
Images ^ SE DEM Plus Image
| Vectorisation (Buildings I : Productio 5
! & Roads) N ÿ nofPre+ |
Figurel. Steps of producing coordinate accurate raster
data
1304
Internati
Figure3
