COMPARISATION OF SPATIAL ACCURACY OF DATA ACQUARIED FROM MONO 
AND STEREO IMAGES :A CASE STUDY OF CAMPUS AREA KONYA -TURKEY 
O. Mutluoglu 3 M. Yakar a H.M. Yilmaz b , F. Yildiz 3 
a Selcuk University, Engineering and Architecture Faculty, Geodesy and Photogrammetry Department, 42075 Konya, 
TURKEY - yakar, omutluoglu, fyildiz )@selcuk.edu.tr 
b Aksaray University, Engineering Faculty, Geodesy and Photogrammetry Department, Aksaray, TURKEY - 
hmyilmaz@aksaray.edu.tr 
Commission IV, WG IV-9 
KEY WORDS: High Resolution IKONOS Images, Feature Points, Geodetic Methods, Ortho Photo 
1. ABSTRACT: 
Nowadays, high resolution IKONOS images for map productions, local municipality studies, communications, agriculture, forestry, 
energy and infrastructure, monitoring of environment, disaster management, determination of natural resources, pipeline, 
transportation, security, defence and GIS studies. Accuracy of spatial is the most important factor in view of the map production 
using IKONOS images.In this study, digital ortho photo maps have been produced using 1 m resolution mono and stereo IKONOS 
images. Mono and stereo images have been covered the same area. Some feature coordinates have been measured from the produced 
ortho photo maps of selected test area. The same feature points surveyed using electronic total stations according to geodetic methods. 
Ortho photo coordinates and geodetic coordinates have been compared. Differences have been calculated and results have been given. 
1. INTRODUCTION 
Nowadays, satellite images have been used for many 
applications intensively. For example, updating existing maps, 
land use mapping, urban planning, disaster monitoring, and so 
on. To use high resolution satellite images in such fields, they 
had to be rectified. Rectification process is done by points, 
which coordinates are known in both land and image. The 
selected points may indicate either measured points in the field 
or/and can be designated as visible points in images. These 
points may represent; building comer, road cross, painting 
objects, etc. 
The launch of IKONOS by Space Imaging opens a new era of 
high-resolution satellite imagery collection and also promotes 
the mapping applications of satellite imagery. The IKONOS 
satellite simultaneously acquires lm panchromatic and 4m 
multi-spectral images in four bands with 11 -bit radiometric 
resolution that are suitable for high accuracy photogrammetric 
processing and mapping applications (Tao et al. 2004). Space 
Imaging provides a broad category of mono and stereo products 
including georectified, orthorectified and stereo imagery 
products with different accuracy levels (Dial 2000, Grodecki 
and Dial 2001). The specified horizontal accuracies of the Geo, 
Reference, Pro, Precision and Precision Plus IKONOS products 
are 25 m, 11.8 m, 4.8 m, 1.9 m and 0.9 m CE90 (Circular Error 
90%), respectively. 
Many investigations related to the accuracy of IKONOS 
imagery by means of some photogrammetric process have been 
reported so far. Zhou and Li (2000) showed the potential 
accuracy (2-3 m) of ground points gained using simulated 1 m 
IKONOS stereo images and the pushbroom imaging principle. 
Fraser and Hanley (2003) achieved submeter accuracy using 
one ground control point (GCP) for bias compensation in 
IKONOS RFs. Toutin (2003) evaluated the potential, the 
accuracy and the robustness of the 3D parametric model under 
different conditions. It was concluded that 20 3-m accurate 
GCPs were a good compromise to achieve a 3- to 4-m error in 
the bundle adjustment, while 10 1-m accurate GCPs were 
enough to achieve a 2- to 3-m accuracy. Wang et al. (2005) 
presented four different models defined in both object space and 
image space to refine the rational function derived ground 
coordinates. It was demonstrated that if an appropriate model 
and GCPs were used, ground point errors could be reduced from 
5-6 to 1.5 m in horizontal and from 7 to 2 m in vertical 
directions. Dial and Grodecki (2003) had tested Ikonos stereo 
accuracy without ground control. They had achieved to absolute 
accuracy at 6.2 m. horizontal, 10.1 m. vertical, and found out 
the most relative accuracy results for points more than 3 meters. 
Due to its superior geometric accuracy characteristics, IKONOS 
satellite imagery is particularly well suited for large scale 
mapping applications [Dial and Grodecki, 2002], [Grodecki et. 
al., 2003]. As for geometric correction of high-resolution 
satellite imagery, acquisition of ground control points is 
important [Kadato and Takagi, 2002]. 
2. MATERIAL AND METHOD 
2.1. Test area 
Alaeddin Keykubat campus area of Selcuk University was 
selected as the test area in order to compare. The campus area is 
located from 20 km north of Konya city center which includes 
10 faculties, 2 vocational high schools, dormitories, social 
facilities such as sports centers, health centers, cafeterias, 
shopping centers, etc (Mutluoglu, 2004). In this study, one pair 
of stereo IKONOS imagery (acquisition date 30/01/2004) and 
mono IKONOS imagery (acquisition date 03/05/2003) 
covering Selcuk University Campus, in the northern part of 
Konya city, were used (Figure 1).