The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B7. Beijing 2008 
5. CONCLUSIONS 
We have presented a newly developed method based on the 
PCA+astrous transform for fusing images. In this paper, an 
experimental study was conducted by applying the proposed 
method, and also other image fusion methods, for fusing 
Quickbird images. A comparison of the fused image from the 
astrous wavelet and PCA method was made. 
This study is a successful experience with the PCA+astrous 
wavelet transform based fusion approach. It is shown that 
proposed wavelet transform approach improves the spatial 
resolution of a multispectral image while it also preserves much 
portion of the spectral component of the image. 
This topic along with further formulation of fusion quality will be 
our future effort of study. 
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Figure.2 (a) Detail of the Quickbird multispectral image. (b)Result of the fusion by astrous wavelet method. (c)Result of the fusion 
by PCA. (d)Result of the fusion by PCA+astrous wavelt method. 
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