Mularz, Stanislaw
set being analysed. The merger of remotely sensed images based on PCA (Principal Component Analysis) concept high
rankings were obtained full set of Landsat bands combinations. For the IHS (Intensity, Hue, Saturation) merging
method relatively low rankings were observed. Another words, the HPF transformation seems to be the best merging
method being tested, than PCA and IHS formulas, when taking into account the average of the amount of the additional
information generated by the merger. Looking at the particular three bands combinations one can easily observed
interesting regularity, that for the Landsat TM (145 and 457) bands the high rankings were obtained, independently of
the merging method have been used. Also the Landsat TM (247) spectral bands might be effectively combined with the
spatial information of aerial photographs.
k123 k134 k234 k154 k247 k457
HPF IHS PCA
k123 k134 k234 k154 k247 k457 k123 k134 k234 k154 k247 k457
Figure 7. The rankings of the merged images for the six subset of Landsat TM band combinations
The relatively less promissive from interpretations point of view and the total amount of information are combinations
which contained in the three-pair subset the four Landsat TM bands (123, 134, 234). This was probably because, low
rankings usually resulted from contiguous band combinations caused by more highly correlation between these bands, if
compared the others. Also the similar conclusions are indicated by Chavez et al. (1984) and Davies et al. (1987) Table
… shows the correlation coefficients of that Landsat TM bands versus th
e intensity (after RGB transformation from
color aerial photographs). It is clearly visible the L
(high correlated), while TM 5 and 7 bands are in
band combinations, which contained one or two o
before and after merging.
andsat TM 1, 2, 3 and 4 bands provide almost the same information
fact different from other (relatively low correlated). Thus, the three
f these channels have been characterised by the largest OIF values,
Table 1. shows the correlation coefficients of the TM bands befo
re and after merging procedures, as well as
panchromatic equivalent image (Ie). Among the thre tested merging methods the HIS distorted the spectral
characteristic of the Landsat data the most. The reason i
s because the intensity image that is replaced by the airborne
(the equivalent of panchromatic image — Ie) can be different depending on the TM bands combination used. In all tested
three band combinations (TM 123, 134, 234, 247, 145, 457) very high correlations with panchromatic equivalent image
(Ie) are observed (Table 2.). The PCA method also distorted the spectral characteristic of satellite TM data, but the
distortions were less then those in the HIS method.
TM1 TM2
O
TM 3
0,975
0
TM 4
0,935
TMS TM 7 Ie
TM 1
TM2
TM3
TM 4
TMS 0 0,622 0 0,430
TM7 0,686 0,691 0,726 0,720 0,938 0,542
Table 1. Correlation coefficients of Landsat TM bands and equivalent of panchromatic image (Ie)
0,691
0,726
0,720
0
712
717
0,702
5 0,975
5
0
3 0 0,975
The HPF method distorted the spectral characteristics of the Landsat data the least. The correlations with panchromatic
(Ie) image were less than those in PCA method. It should be stressed that in SWIR bands (TM 5 and 7) after merging
the spectral information contents were preserved better than in the visible (TM 123) and near infrared (TM 4) bands. In
PCA and HPF method correlation coefficients were low contrary to expectation.
An important result of the merger is that the different three-band combination furnished valuable lithologic information
for detection and recognition of the geological units within the overburden as well as lignite deposit in the open-pit
mine. Furthermore, geologic analysis was simplified by both color and spatial information. It is evident also, that the
924 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.
TMI
