ad 
Ahmed Elaksher 
  
  
ATE 
—-COST 
150j- 
Ha of points 
  
  
  
  
  
Figure 9. Error Distributions from the the COST and ATE Systems 
5 CONCLUSIONS 
This paper has described an integrated stereo matching technique for object -surface reconstruction. The matching 
problem is addressed by the integration of both signal and feature based approaches. To address stereo matching in 
urban area images, we developed two innovative features, i.e., the plateau and spike. The classic dynamic programming 
for feature matching is modified and enhanced to integrate signal and feature matching into a simultaneous 
profile/surface determination. The initial global error statistics indicate that no improvement has been achieved over 
strictly correlation based methods. However examination of some individual area (see Figure 7) indicate that the 
methods offers promising potential in exactly the circumstances where area correlation is weak. This approach can be 
further developed with other features, other match criteria, and improved search methods to yield even better results in 
the future. 
ACKNOWLEDGEMENTS 
The work described in this paper was partially supported by the U.S. Army Research Office under Grant Number 
DAAHO4-96-1-0444. The authors would like to acknowledge the support of Dr. Edward Mikhail, the project director. 
They would also like to thank Ahmed Elaksher for his help in data analysis. 
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ta 
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B3. Amsterdam 2000. 273