var dio 
  
  
Fig. 10 The blue band of a scanned aerial photograph of 
an urban area, size 256?, pizelsize 1.60m. The lower image 
shows the outlines of the detected regions after passing the 
entire procedure. 
6.3 Real Images 
Aerial Photograph (fig. 10a). Smoothing doesn’t im- 
prove the results, due to the inherent removal of details by 
smoothing. Predictor parameters: see SB image. Exper- 
iments on setting the confidence levels yielded for Stage I 
the range [95% — 99%]; for Stage Ila 99.9% was the only 
reasonable setting and for Stage IIc 9596 was a good option. 
Final region outlines are shown in fig. 10b. 
  
800 
  
Fig. 11 Landsat TM image of the Dutch Flevo Polder, 
size 128?, obtained by summing up band 3, 4 and 5, and 
rescaling the result to fit into the range [0-255]. The lower 
image shows the outlines of the detected regions after pass- 
ing the entire procedure. 
Landsat TM Image (fig. 11 a). Predictor parameters: 
see SB image. Optimal confidence level settings are: Stage 
I 95%; Stage Ila 9996 and Stage IIc 95%. Note that in 
Stage Ila, the confidence level is 99%. A confidence level of 
99.9% yields too much merging of regions, due to the low 
grey value differences between many parcels. 
m et pd AN ad |