ISPRS Commission III, Vol.34, Part 3A „Photogrammetric Computer Vision“, Graz, 2002 
  
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(a) Three steps of interactively extracting a road line, (Left #1: result after assigning the starting point, Left #2: result after assigning 
the 1* directional point, Right #1: final result) 
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(b) Enlarged figure of area “A”, (Left 41: result of road line extraction, Left #2: IKONOS image, Right #1: road mask and road 
seeds). 
Figure 12. Extracting a road line 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
(b) Countryside 
Figure 13. Generating road map of a specific area (Left #1: road mask and road seeds, Left #2: IKONOS image, Right #2: road lines 
that are extracted, Right #1: 1:25,000 road map) 
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