International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B1. Istanbul 2004 
  
2.3 Component Development for Fusion 
Main components to be developed in this study were data 
input component, filtering component for image improvement, 
image analysis component for such as geometric correction of 
images, image fusion component and output component. For 
image fusion component, modules for IHS and Wavelet method 
were developed. 
3. EXPERIMENT BY FUSION METHOD 
3.1 IHS Fusion Method 
The image fusion method using color models of IHS(Intensity- 
Hue-Saturation) had been firstly used by Hydan in 1982. Since 
then, it has been the most common method. IHS fusion method 
applies IHS transformation to three low resolution images 
existing on RGB color models and creates intensity images, 
hue images and saturation images(Jensen, 1996). 
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Whereas, intensity images(grey image) include information 
related to spatial resolutions of low resolution images and hue 
images and saturation images contain data related to spectral 
resolutions. Thus, when intensity images are replaced by high 
resolution images with good spatial resolutions, spectral 
resolutions of low resolution images and spatial resolutions of 
high resolution images are combined. These images become 
fusion images of high resolutions containing plenty of spectral 
resolutions of low resolutions through RGB transformation. 
IHS transformation method is easy to apply, but allows only 
three bands to be applied. 
3.2 Wavelet Fusion Method 
Multiple resolution Wavelet transformation has been recently 
studied. It has been applied to signal processing and image 
processing in various ways. In particular, it has been widely 
used for image compression, boundary extraction, object 
recognition and image fusion in image processing (H.H.Kang 
et al., 2001; Garguet-Duport et al. 1996). 
When applying Wavelet transformation to images, one rough 
image and three precise images are obtained. At this point, a 
rough image contains data related to spectral resolutions of 
images and three precise images contains spatial resolutions 
according to directivity. Therefore, Wavelet fusion method 
applies Wavelet transformation to high and low resolution 
images using properties of Wevelet transformation, replace a 
rough image of low resolution image by that of high resolution 
image and then, carries out Wavelet reverse transformation 
using a rough image of low resolution image and precise 
images of high resolution images. Wavelet transformation 
formula is defined as follows(Sunar et al. 1998). 
Wa, b= [ A) C0), a»0, be R 
v la] a (2) 
a : scalar Factor 
b : translation Factor 
(1) : mother wavelet 
Approximation 
Image (change) 
Horizontal detail 
image 
Vertical detail 
image 
Diagonal detail 
  
Figure 2 1 pass diagram of Wavelet method 
Figure 2 describes image fusion processes using sample 
images applied in this study. Firstly, as applying two-step 
Wavelet transformation to KOMPSAT with high spatial 
resolution, approximate images and detailed images with the 
same size as LANDSAT images with low spatial resolutions are 
obtained. Next, approximate images on the second step are 
replaced by each multi-spectral image and then are reversely 
transformed. Accordingly, the images are fused as multi- 
spectral images with three spectral bands having high spatial 
resolutions. 
4. DEVELOPMENT OF IMAGE FUSION COMPONANT 
This study created component-based program using object- 
oriented concept to perform pre-processing function and image 
fusion function for image fusion. Figure 3 shows overall layout 
of image fusion system. Figure 4 explains links among classes 
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Figure3 Diagram of Fusion System. 
and data flow for image fusion. System implementation largely 
consists of image input sector, fusion sector and output sector, 
in which fusion sector contains fusion modules and image filter 
modules of IHS and Wavelet. 
  
Source & Result 
Image FR Method Fusion 
Management election Execution 
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Figure 4 Work Flow of Class and Data 
  
  
  
   
  
  
   
   
    
   
    
  
   
   
  
    
    
    
    
   
    
   
    
    
   
  
  
    
     
  
   
    
   
   
    
  
   
    
    
      
        
   
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