International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B-YF. Istanbul 2004 
water body and other regions. Figure 2 shows the initial 
shoreline extracted from the image. 
The initial shoreline extracted from image is superimposed on 
the segmented images. By visual checking, one can see that as 
the boundary of the initial shoreline is generally at the correct 
position; a method is needed to correct the deviated shoreline 
portions either automatically or interactively. In our case study, 
it is easy to extract the shoreline. The extracted shoreline 
developed in a GIS setting by manually selecting the correct 
boundaries. Figure 2 shows that the extraction of shoreline had 
been accepted while; it is difficult to locate the breakwater, so it 
can be added manually. Also we can use the edge detection as 
shown in Figure 3. 
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Figure 3 Edge detection for the shoreline. 
5, 
Figure 1 The different four satellite images for the studied 
area of Port Said during the years 1991,1995, 1998, and 2001 6. CONTROL POINTS AND 
CORRDINATES TRANSFORMATION 
Control points and coordinates transformation are required to 
achieve good accuracy satellite imagery, and reference 
information. 
4. SHORELINE GENERATION 
After removing the noise from the images, a raster-to-vector 
conversion is applied to the images. All the segmented regions 
are represented as vector polygons. The major water body can 
be identified from the other regions using statistical and shape 
information. In our experiment, the region with the biggest size 
is recognized as the major water body. Then the initial shoreline 
is automatically extracted from the boundary between the major 
The ground control points must be clearly discernable on the 
ground as well as in the image. They were taken to ensure that 
the correct points are obtained. The available data for the 
ground control points are obtained from GPS. Control points 
were taken on the western breakwater at the entrance of the 
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