4.3 Geometric correction 
On the image processing system satellite images are registered to the 
map image data. This may be done by using a split screen and 
displaying the two images in each half. Both images can be zoomed or 
roamed and by picking corresponding points in the two images the 
coefficients of the tranformation formula may be calculated. The 
final processing is done by the Warper of the Model 75 image 
processor. | 
4.4 Raster/vector convertion 
As vectorizing always is performed on binary data, images must be 
slized using a lower and upper threshold to produce binary data. Then 
the data are converted to the compressed format (run length coding) 
used by the scanner (Module IIS2LSC). The data is then vectorized 
using standard SysScan software which produces boarder lines from 
polygons and lines from linear features. (Module MONITOR) 
4.5 Storing of data in Map Information System 
1f data from the image processing system contains header information 
about transformation to user coordinates, the data may be loaded into 
a specific layer or sublayer in an existing vector file. (Module LGSW) 
5. APPLICATIONS 
The modules described above gives the user the opportunity to 
integrate data from both systems. Image-maps with different overlays 
from the map system are easily produced. Information from the map 
system are used as ground truth when selecting training areas for the 
classification process which simplifies and improves the 
classification. Such classified areas are then used for updating the 
map system. 
Below is shown the result from a processing where an image from the 
Thematic Mapper has been registered to the layer River in the mapping 
system (figure 2). This transformed image has then been classified, 
and one of these classes has been used for entering new data into the 
map system as shown in figure 3. 
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