Manfred H. Günzl 
  
improve the segmentation quality slightly. As an example using SCV - uA(7,,,,, P)/ l5s gives a result of e — 0.73 shown 
in image 6(f). Where / is the length of the boarder to remove and 4 is Zadehs S-Function used to control the influence 
of r,,,,, dependent on the segment size P. 
4 CONCLUSIONS 
The application of the shape parameter r;,,. in a region growing algorithm pinpointed two mayor problems. 
e The decision of a further fusion step needs to be derived out of a combination of radiometric and geometric param- 
eters. Even if both of them are sources of evidence they can disturb each other if combined to a merging criterion. 
Applied on single look SAR date with a signal to noise ratio of one in most cases the application of a shape param- 
eter leads to worse results as shown in image 6(e). In the early stage of the segmentation the correlated speckles 
with there compact shapes are increased. Using more complicated operators and weighting parameters to combine 
radiometric and geometric parameters can solve this problem. The drawback that prevents the practical application 
is that right now there is no way to derive these parameters from a priori knowledge. The better the signal to noise 
ratio the less critical the combination of radiometric and geometric parameter is. 
e The second principal problem is the application of r,,,. in greedy algorithms. Trying to keep segments as rectangular 
as possible during the entire segmentation process sometimes prevents the algorithm from finding large rectangular 
objects that need to be assembled out of non compact shapes. Comparisons with simulations of uncorrelated speckle 
showed that this is particularly valid when applied to data with correlated speckle. 
ACKNOWLEDGMENTS 
These investigations are a part of the EMAP project. EMAP is equally financed by the German Aerospace Center (DLR) 
and the German Federal Ministry of Agriculture (BML). The test site is located in southern Bavaria between Munich and 
the Danube river. Three sequences of 7-8 ERS-2-SAR-SLC images per year, acquired between March and October, have 
been kindly provided by the European Space Agency (ESA). 
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B3. Amsterdam 2000. 357