= 
  
        
   
  
  
      
S 
y 
| sll) 
2 
533 
    
     
Figure 9: Surface interpolation by a weak membrane. 
    
     
fr 
SA 
Figure 10: Detected break lines in the surface. 
Ongoing research is addressing the following issues: 
e Increasing the degree of automation of surface interpo- 
lation. 
e Subpixel accuracy in the determination of a break line. 
e Defining the means to convey discontinuity information 
to other modules and levels. 
e Integration of other cues for discontinuity, such as the 
residuals between successive levels of surface represen- 
tation. 
References 
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