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pixels to the 
ıtion for the final 
lar pixels (within 
ation 
option was used 
the image menu 
id pixel amount 
caly filtered Test 
w in Table.l and 
n 
get 
Tot. 
Pixels 
3374 
3226 
3181 
3167 
3183 
3213 
3163 
3238 
3226 
3226 
  
  
n 
ge#2 
Tot. 
Pixels 
2401 
2434 
2385 
2401 
2383 
2469 
2473 
2452 
2407 
2350 
  
s freely while the 
es of the defined 
e edges and the 
selection and its 
ons to determine 
value in pixels 
; which will be 
isitivity to edges 
at differs highly 
ue allows lower 
( rate between 
cy means close- 
.dobe Photoshop 
ing and feather 
ind blurriness is 
ake the selection 
els (in diameter) 
by the software; 
edge contrast was chosen to be 20% after some trial. This value 
can be chosen according to the color or contrast between the 
scar and normal skin and frequency 75 was considered enough 
to make a sufficient border 
Table3. Magic Wand process on 
Homomorphicaly Filtered Test Image#1 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
; Std. Tot. 
No. Mean | Median Dev Pixels 
1 114.48 114 10.44 3336 
2 114.76 114 9.04 3238 
3 113.94 114 8.82 3262 
4 114.54 114 9.49 3297 
5 113.99 114 9.49 3297 
6 114.16 114 8.87 3267 
7 114.22 114 9.17 3261 
8 114.65 114 10.42 3347 
9 114.66 114 8.32 3217 
10 114.04 114 8.32 3217 
  
Table4. Magic Wand process on 
Homomorphicaly Filtered Test Image#2 
  
  
  
  
  
  
  
  
  
  
  
: Std. Tot. 
No. Mean | Median Dev. Pixels 
1 128.90 127 8.71 2422 
2 128.67 127 8.34 2391 
3 128.85 127 8.58 2418 
4 128.90 127 8.86 2411 
5 128.74 127 8.31 2412 
6 128.51 127 8.13 2378 
7 127.99 127 7.14 2332 
8 128.17 127 7.41 2357 
9 128.42 127 7,73 2380 
10 128.94 127 8.80 2422 
  
  
  
  
  
  
  
7.3 Comparison of the Results 
First of all, there is a significant difference in the amount of 
pixels selected when the two methods are used. During the 
application it was observed that the magic wand tool can 
exclude some pixels (from of manual operator's selection) 
depending on the tolerance value that is specified. This effect is 
shown in Figure.9. Red squares show the pixels which are not 
included in the selected area. 
Another reason can be that, magnetic lasso is an operator 
depended tool. Operator selects the points and creates border 
manually from the beginning. 
This enables the person to decide the extensity of the edging. In 
that way, the operator might select a wider border that he thinks 
it is part of the scar. On the other hand the magic wand tool is 
an automated tool that only results according to the digital 
numbers of the selected pixel. 
  
  
  
  
Figure 10. Pixels which are not included at result of Magic 
Wand tool process 
    
     
     
    
    
         
   
   
   
     
     
           
   
  
   
   
    
    
     
   
  
    
  
     
   
   
     
     
    
    
  
    
   
Standard deviation rates are higher in magnetic lasso selection 
process. This can be the effect of exclusion of outlier pixels 
over scars by the magic wand tool. Also standard deviation 
represents the variation among the pixels in the selection area 
which reveals their difference in digital numbers. However, this 
does not mean that these pixels do not belong to the scar. 
7.4 Quantitative Analysis on Filtered Images 
Filtered images were chosen according to their results which 
were considered most accurate or suitable to represent the 
whole scar on the skin by using overlay visualization of filtered 
and original images. Because filtered images are only black and 
white images, magic wand tool is enough to calculate the 
amount of pixels and also it is enough to execute the tool once 
since there will be no change in the digital number of the pixel 
that is chosen by the operator inside the region of the scar. 
Table 5.Magic Wand tool applied on filtered images 
Test Test 
  
  
Filters Image Image Diff, 
#1 #2 
Photocopy: Det:24 -Dark:5 2409 
Trace: Lower: 128 
Photocopy: Det:24 -Dark:5 
Trace: Lower: 170 
Photocopy:Det:24 -Dark:10 
Trace: Lower: 128 
Photocopy: Det:24 -Dark:10 
Trace: Lower: 170 
Photocopy: Det:24 -Dark:5 
Thresh: Lower: 128 
Photocopy: Det:24 -Dark:5 
Thresh: Lower: 165 
Photocopy: Det:20 -Dark:5 
Thresh: Lower: 200 
  
3500 2569 931 
  
3637 2682 955 
  
3783 2832 951 
  
2409 
  
3473 2547 926 
  
3537 
  
  
  
  
  
  
7.5 Comparison between Homomorphic Images and 
Filtered Images 
When the Test Image#1 and Test Image#2 are compared, it can 
be seen that total pixel amount difference calculated by magic 
wand tool is less on homomorpicaly filtered images than 
enhanced images (different filter applications). The reason of 
this difference is that, filters comprise some pixels from upper 
part which has lighter red color than main scar. But when the 
magic wand tool was used on non-enhanced images this part is 
not counted as adjacent pixels. See Figure 9. 
8. CONCLUSIONS 
As a conclusion, all the performed tests show that it is possible 
to use the filters mentioned above for the determination and 
monitoring of skin disorders. On the one hand they have 
achieved satisfactory results and on the other hand the software 
used (Photoshop) is user friendly and requires no special 
training or skills to use. The combination of the “Trace Contour 
- Photocopy” filters provides good results which are easy to 
interpret and provide some conclusions because they show not 
only the original image but also the border. On the contrary; 
"Find Edges-Photocopy-Trace Contour" filters don't reveal 
exact boundaries. Parameters of filters are also another aspect 
which needs to be considered in further investigations 
concerning also the hurt area size on the image.