The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B7. Beijing 2008 
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three fusion methods used in the paper. The result of 
quantitative spatial analysis is consistent with the initial visual 
interpretation (Fig. 3(b), Fig. 4). 
3.3 Results on IKONOS Images 
A sub-scene of IKONOS image taken on 28 March 2003 is 
selected as the other kind of test data, which covers an area of 
the urban area of Dujiangyang city in Sichuan province China. 
The size of selected HSR image is 1600x1600 pixels (400x400 
pixels for LSR images) and Fig.5 is the original HSR image 
(308x152 pixels ) and LSR images. 
Figure 5. Original HSR and LSR images of IKONOS. (a) HSR 
image, (b) RGB false-colour composition 4, 3 and 2 of LSR 
(resampled at 1 m) 
Fusion method 
Spectral quality 
Spatial quality 
SD 
ERGAS 
CC 
ERGAS 
MSI 
0.002 
0.894 
SFIM 
MS3 
0.001 
0.001 
0.553 
0.919 
0.924 
83.396 
MS4 
0.001 
0.910 
MSI 
0.010 
0.712 
DWT 
MS3 
0.010 
0.018 
6.887 
0.739 
0.750 
87.621 
MS4 
0.021 
0.707 
MSI 
0.210 
0.958 
MBT MS3 
0.211 
0.213 
85.201 
0.981 
0.973 
57.881 
MS4 
0.217 
0.922 
Table 2. Quantitative evaluation results of IKONOS 
From the fusion results of IKONOS images (Fig. 6), the spectral 
information of three fusion methods is almost the same with 
original LSR images (Fig. 6, Fig. 5(b)). On the other hand, the 
features in fused images are clearer than that in original LSR 
images. However, the edges between different features are 
blurred in SFIM-fused images or WT-fused images (Fig. 6(a)- 
(b)), and the features in MBT-fused images are clearer 
compared with SFIM-fused or DWT-fused productions (Fig. 6). 
Figure 6. The fusion results of IKONOS. (a) RGB false-colour 
composition 4, 3 and 2 of SFIM. (b) RGB false-colour 
composition 4, 3 and 2 of DWT. (c) RGB false-colour 
composition 4, 3 and 2 of MBT 
From Table 2, the index SD values of SFIM-fused images are 
the lowest. The spectral ERGAS and average SD values of three 
fusion methods are 0.553 and 0.001 (SFIM), 6.887 and 0.015 
(DWT), 85.201 and 0.213 (МВТ), respectively. So, both 
average SD and spectral ERGAS indexes of SFIM-fused images 
are more close to zero compared with those of DWT or МВТ 
productions. In other words, SFIM fusion method has superior 
spectral information preservation with LSR images of IKONOS, 
followed by DWT and МВТ. When we come to the spatial 
quality evaluation indexes CC and spatial ERGAS. The value of 
CC index between either band MBT-fused images with HSR 
image is the highest. The average values of CC index of three 
fusion methods are 0.912 (SFIM), 0.727 (DWT), 0.959 (МВТ), 
and the spatial ERGAS indexes of three fusion methods are