e (a),
VILDF
Wn in
orrect
lively.
g time
band
s 3,4
j MLH
Table 3 Confusion matrix for MLH, BDT and MLDF.
Category
Area 1 2 3 4 5 6 Z 8 9 10 11 12 13
Se hala b am 12.00 | P
Oed ey CT Taw yup 02510
[87.25] aol N° ins] ——
uw JL enl N js LÀ | cie 064
oe | Teu D lea DI esq $98.
93.73 4.27
a pd NM d 1. dp
gl 1 1 283] 494] |. 1 ds TUTTI
F 100.00 s
a) ct shes oz i essi ot ed off fT] AL BT TT lo» oos
2 T beu Tn TN. affuit HR LE Lis um
97.95 0.17 1.88
100.0€
s De To T iab Sg orlhecqon SEES TT EEE
Bisher Tita abs s adqéte br inioalvaal Th A
22 97.78
Sale 1]5ont23]:o39. 1. H: outiliits Fo COG i ae rs.
sole | 123] il 67. rt ad LPS OOtdes |
1.67 98.33
aille. ] Ÿ TR}
| 331 96.67
“V0 rst hci heed. C1
$T Ep OT ET TE St
2.08 | 97.92
[Sed oer cabe bete. Su s i
9 AR] d l1 t | 96.27
El TT TIE OLE ka ^
1.23 98.77
Er I TT II eT ya
98.77| 1.23
[asl s ied be e.a Oa] alt lo gS fa dose Lait
nl | pagan} Yc b SEA 1| AUN
100.0C
Po] OI A e-0 uw T RT ases oo
glos | i|! egl.. [em] ow A0) es tfonss icon
11.18 4.66 84.16
elei Ie xs I 100.00)
BL i j.ve Tel Ah NS ] dia 3:4 M. 99.38
100.00
Table 4 Mean correct classification rate for
MLH, BDT and MLDF.
5 band 3 band
Method| Accuracy |Time | Accuracy | Time
MLH 96.79 [%] |303 [s]| 95.48 [96]| 133 [s]
BDT 89.03 18 90.88 11
MLDF | 94.06 20 92.73 19
and 5, and evaluate the change of accuracy and efficiency
using the identical training and test areas. Table 4 tells us
that MCCRs slightly decrease or almost the same accordingly
to reduction of number of spectral bands five to three, and
that processing time in both MLH and BDT depends on the
number of spectral bands. In MLDF, processing time fully
depends on size of binary division tree, therefore, much
information brought by larger number of spectral bands may
331
gives more suitable division boundary which efficiently
reduces size of the tree. This is the reason why processing
time of MLDF in classification of 5 spectral band image is
almost as same as that of 3 band image. There is possibility
that MLDF is more efficient than BDT.
CONCLUSIONS
We proposed a highly accurate and efficient method MLDF
for supervised classification of remotely sensed multispectral
images. The method MLDF is expanded from BDT which is
very efficient. Image data are projected onto eight 1D
subfeature spaces to produce histograms with compression
of data. The division boundary is selected among all valleys
in histograms using a clustering criterion that the optimal
boundary minimizes the ratio of sum of within-group-sum-
of-squares to intragroup-sum-of-squares. MLDF produces
binary division tree by applying the division process
recursively. Each node of the tree has coefficient vector for
data projection and threshold for data division.
As division boundary in histogram corresponds to hyperplane
in full feature space, MLDF is regarded as a kind of linear
discriminant function method. On the other hand, as no
statistics for training data is used in selection of division
boundary, MLDF is also regarded as a nonparametric
supervised classification method. From evaluation of
performance using artificial image and actual remotely
sensed multispectral images, it is confirmed that MLDF has
as high accuracy as MLH does and as high efficiency as
BDT does. Improvement of MLDF in term of efficiency and
analysis of classification with less generality training data
are subjects for a future study.
REFERENCES
Fujimura, S. et al.,, 1978. Comparison of automatic
classification methods for multispectral images. Trans. Soc.
Instr. Contr. Eng., 14(3). pp.269-276. (Japanese)
Inamura, M. et al., 1979. High speed processing of the
multispectral Images by means of binary decision tree. Trans.
Soc. Instr. Contr. Eng., 15(4). pp.486-491. (Japanese)
Hanaizumi, H. et al., 1995a. A binary division algorithm for
clustering remotely sensed multispectral images. IEEE
Trans., IM-44 (3), pp.759-763.
Hanaizumi, H. et al., 1995b. A binary division algorithm using
a linear discriminant function for the cluster analysis of
remotely sensed multispectral images. Proc. SPIE-2579.
pp.182-187.
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B4. Vienna 1996