International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B3. Istanbul 2004 
  
[= lower cutoff of the shadow area 
H = upper cutoff of the companion area 
L = lower cutoff of the companion area 
Gamma - the control parameter 
CAIM maps the upper and lower cutoffs of the shadow area to 
the upper and lower cutoffs of the companion area respectively, 
and so for the means of the shadow and companion areas. Thus, 
the gamma parameter can be decided by the averages of the two 
areas. 
The intensities at the edges of the shadow area are higher than 
those in the inner, because the illuminating condition is a little 
different at the edge from in the inner. They generally belong to 
or close to the upper cutoff of the shadow area, and become very 
bright after restoring. This edge effect is reduced by smudging. 
4. THE RESULT AND DISCUSSIONEA 
We made experiments using ADS40 image of level 1 and the 
associated data to test our shadow detection and shadow removal 
method. The study field is in Tsukuba, Japan. The resolution of 
image and DSM is 20cm and Im respectively. Figure 6 shows 
some patches of the image and the effects of 
  
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