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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B7. Istanbul 2004 
For manual lineament extraction the image is first smoothed 
with an average low pass filter in order to eliminate the noise. 
Following the smoothing process, directional filtering method is 
selected for the lineament extraction because the directional 
nature of Sobel kernels generate an effective and faster way to 
evaluate lineaments in four principal directions (Süzen et 
al.,1998). 
The Sobel kernels in four principal directions are given in Table 
1. 
  
N-S NE-SW E-W NW-SE 
  
1 
N 
© 
N 
1 
e 
e 
e 
e 
1 
© 
  
  
  
  
  
Table 1. Sobel kernels in four principle directions 
A lineament in an aerial photo or a space image can show up 
either darker pixels in the middle and lighter on both sides: or, 
is lighter on one side and darker on the other side. When 
directional filtering is applied to the image the lineaments show 
up in light color which is surrounder by dark colored pixels. 
After the filtering operation, the lineaments are digitized 
manually with a scale of 1:1500. There are 3357 lineaments 
with total length of 130040 meters in the study area. 
4. RESULTS 
For the comparison of the manually digitized and automatically 
extracted lineaments more effectively, the manually extracted 
lineament map is subjected to further. 
The raw image contains agricultural fields in the north western 
part and village houses in the south western part. Because of 
this an area of interest is produced by excluding these areas by 
digitizing. In the reference lineament map, that is produced by 
manually, a boundary for the area of interest is formed. The 
automatically extracted lineaments are overlaid by the reference 
data and the lineaments in the restricted areas are deleted. 
Not only the field boundaries and village but also the mine 
roads are seen as a lineament in the automatic extraction 
process. Hence the vectors that corresponds to the roads of the 
mines are also deleted. The resultant lineament map produced 
by manual digitizing is given in figure 3. 
  
  
LS 3 LT 
Figure 3. Manual Digitized Lineament Map 
The automatically extracted lineament maps are overlayed with 
the area of interest and the lineaments outside this area are 
deleted. The andesite mine roads are easy to detect so the roads 
are also deleted. After these processes the length and number of 
the automatically extracted maps are found. 
The parameters for the LINE process are given Table 2. 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
a 
= 1 BYR R{& PE |Z 
Zz Z = km = E = 
3 Q - EX « e 
VEC 1 5 20 | 40 2 20 je 1. 
VEC 2 5 20 | 20 2 20 
VEC 3 5 20 | 15 2 20 1 
VECA | 5 20 | 25 2 20 1 
VEC5 5 30. 1 45 2 20 
VEC6 | 5 30 ] 20 2 20 I 
VEC 7 5 0 | 15 2 20 
VICE | 101 40] 75 2 20 1 
VECY | 12 1 0 | = 3 20 
VEC 16] Dl 10 | 35 3 30 1 
VECH | 12 | 20 | 25 3 40 ] 
VECIOI 12 1 0] 20 3 30 1 
VEC | 2 | 30 1 30 3 20 1 
VECM | 12 1 0] 5 3 20 1 
VECIS | 2 (0 | 2 3 20 ] 
VEC 16 [12 | 40 | 25 3 20 1 
VECITI 12 | so [| 25 3 20 1 
VECIS | 12 | 40 | D 3 20 1 
VECAIS | 12 [| 50 | 20 3 20 1 
VECO 12 | a0 | is 3 20 
VEC 21] 42] 50 | 15 3 20 1 
VEC22 | 12. ] e0 | 4s 3 20 
VEC | 12 | 60120 3 20 ] 
VEC24 | 12 | 0 | 25 3 2 
VECOS | 0 ] 100.15 3 2 1 
  
  
  
  
  
' Table 2. Parameters of LINE Process 
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