ISPRS, Vol.34, Part 2W2, “Dynamic and Multi-Dimensional GIS", Bangkok, May 23-25, 2001 
Fig.5: Orthorectified and georeferenced IKONOS2 image according to GCOs of a DGPS mapping (red lines and points). 
The georectifying was done for the panchromatic file as well as 
for the four multispectral files. Then a first supervised 
classification was done with the green and the near infrared 
channels by using the results of the DGPS mapping again. In 
Fig.6, the result for an area of this image processing step is 
displayed. The field right next to the east of the experiment field 
is used for rice cultivation. It is clearly visible that the high 
resolution of the image even enables the identification of small 
water channels for irrigation. Because the classification was 
done for the differentiation of agricultural land use, the red color 
displays a broad spectrum from bare lands, settlements, roads 
etc.. In some fields a high proportion of bare land is classified 
which derives (i) from different land use (some crops already 
harvested) or (ii) less plant density. 
Fig.6: Supervised land use classification of IKONOS2 image (green: wheat/maize; bright green: rice; dark green: 
orchards and trees; red: bare land and all kind of settlements; blue: water)