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