The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B7. Beijing 2008
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system [4] . Image registration include relative registration and
is call for the error control within a single pixel in the high-
resolution images, or within the pixel size of 10% ~ 20% in the
low-resolution multispectral image ^ 5 l
In this study, use the relative registration method, take the
panchromatic band of ETM + images for the reference image,
select forty-six control points to make geometric correction
absolute registration [x! ,the general requirements of registration
with the multispectral images, in order to reduce loss of
spectrum by resample, use the nearest neighbour method to
resample, the accuracy of registration is controlled within 0.3
pixel, which can meet the need of registrations accuracy.
ETM+1
ETM+2
ETM+3
ETM+4
ETM+5
ETM+7
ETM+1
1
ETM+2
0.952
1
ETM+3
0.846
0.927
1
ETM+4
0.626
0.611
0.436
1
ETM+5
0.645
0.719
0.712
0.690
1
ETM+7
0.678
0.780
0.864
0.465
0.891
1
Table 1 Correlation coefficient matrix table
Bands
combination
OIF index
Range order
Bands
combination
OIF index
Range
order
123
12.832
1
134
22.605
11
127
16.739
2
157
22.724
12
124
17.229
3
357
22.840
13
237
18.043
4
245
23.918
14
125
18.359
5
145
24.316
15
137
19.160
6
247
24.858
16
135
19.693
7
147
25.724
17
235
20.596
8
457
27.442
18
257
21.314
9
347
29.209
19
234
22.169
10
345
29.230
20
Table 2. The OIF index of different bands combination (according to the order from small to big)
3. COMMON FUSION METHODS
In this study, the fusion methods are all based on pixel-level
fusion method, pixel-level image fusion method is a process to
analysis the original information, this fusion method loss the least
information, so the accuracy of the pixel-level fusion is the
highest, but the data transmission and processing is the largest. [6] .
3.1 Fusion Methods
pixel (tî) show the high frequency information of
the high-resolution panchromatic image.
3.1.2 SFIM Fusion Method: The full name of SFIM
transform is called Smoothing Filter-based Intensity
Modulation^,which is a brightness transformation based on
the smoothing filter. The formula of this arithmetic is as
follows:
3.1.1 High-pass Filter Fusion Method: High-pass filter fusion
method a method that make the high frequency components of
high-resolution panchromatic image superimposed on low-
resolution multispectral image, to obtain the enhanced spatial
resolution multispectral image. The formula is as follows:
»,=SZ
B.,_ xB
h 'S^ jk
i = 1,2,3
(2)
F k (i,j) = M k (i,j)+HPH{i,j)
In the formula, p (ij) is the fusion value of the band k pixel ^,
the value of multi-special of band k
In the formula B is the fusion image generated by this
arithmetic, i is the value of the band, j and k is the value
of row and line; Ti is the Low-resolution images, here
denote the multi-spectral band of ETM+; B h is the high-
resolution images, which is the panchromatic bands of ETM+;
D
mean j s simulate low-resolution images, which can be