the extracted 
d using all the 
ortho-rectified 
y are merged 
one where the 
complemented 
es. Figure | 
ith the merged 
  
to with partial 
same scen 
    
    
    
| true ortho- 
he scene 
n 
) is computed 
bands of the 
(1) 
d to tune the 
ording to the 
).2) and high 
0.2) and low 
. 
wo conditions 
i| images and 
of the city of 
'e provided by 
| 3D building 
gs with rather 
dings that are 
ea with small 
art of the high- 
  
resolution DMC block of the DGPF test (Cramer, 2010). They 
were acquired using an Intergraph/ZI DMC by the company 
RWE Power on 24 July and 6 August 2008. In total, the block 
consisted of five overlapping strips with two additional cross 
strips at both ends of the block. 
  
Figure 2. The three test areas shown on DSM 
The images are pan-sharpened colour infrared images with a 
ground sampling distance of 8 cm and a radiometric resolution 
of 11 bits with known interior and exterior orientation 
parameters. 
The Vaihingen data set also contains Airborne Laser Scanner 
(ALS) data. The entire data set consists of 10 ALS strips 
acquired on 21 August 2008 by Leica Geosystems using a Leica 
ALS50 system with 45? field of view and a mean flying height 
above ground of 500 m. The average strip overlap is 3096, and 
the median point density is 6.7 points/m^. Point density varies 
considerably over the whole block depending on the overlap, 
but in regions covered by only one strip the mean point density 
is 4 points/m/?. In addition to the original ALS point cloud, a 
digital surface model (DSM) is provided. This DSM was 
interpolated from the ALS point cloud with a grid width of 25 
cm, using only the points corresponding to the last pulse. 
To quantitatively evaluate the proposed approach, the obtained 
classification results are compared to reference data acquired 
using photogrammetric plotting. The evaluation is based on the 
technique described in (Rutzinger et al., 2009) that provides 
completeness, correctness, and quality of the results both on a 
per-object and on a per-area level. The 2D RMS error of the 
object outlines of the correct objects are also provided to be 
compared with those of the reference data. 
Figure 3 shows the generated true ortho-photo for the first area, 
and Figure 4 illustrates the classification results of the buildings 
class for the first area. Figure 5 depicts the classification results 
of the trees class for the first area. 
Figure 6 shows the generated true ortho-photo for the second 
area, and Figure 7 illustrates the classification results of the 
buildings class for the second area. Figure 8 depicts the 
classification results of the trees class for the second area. 
    
   
    
     
    
   
  
   
   
  
   
   
  
    
     
   
   
  
   
   
     
   
     
    
    
  
     
   
   
  
  
Figure 4. Buildings classification (correctly classified as 
yellow, misclassified as red, missing as blue) 
  
PS xr. 
.* 
* P 
5 
$ 
d 
9 À. : 
2 » 
* 5.9 = 
, # 
(S, ad 3 "d 
* ; 1 oF So 
2 ^ 
f», 2 ex 
I? 
ug, °° 
Figure 5. Trees classification (correctly classified as yellow, 
misclassified as red, missing as blue)