ware in the
he National
olygons of
lade buffer-
reasing the
the stand's
ining areas.
ing time of
1e different
shaped at
hairy oak,
ne, Spruce.
> first band
ause of the
remove the
I” strips are
and the VI.
d from the
opographic
d the DTM
| vegetation
s.
relation
cient
SRT EE)
on with the
, when the
able.
Then the radiometric normalisation of each bands with the above
parameters was made by the following equation (Equation (1))
P
m mM 1
m-cosa +b 0)
I started the classification with the above 10 classes, at first. The
classification method was based on maximum likelihood
algorithm using empirical probability density (Czimber, 1995).
Then I joined and deleted some classes because of the overlaps.
Thus seven classes left, which were the followings: robinia, oak,
hombeam, beech, larch, scotch pine - spruce, austrian pine. The
error matrix of the hole forested test area classified by the above
method is shown in Table 6. The error matrices of the common
minimum distance and maximum likelihood classification are
showed in the Table 7. and 8. for the comparison.
Rob. |Beech |Sc. p. -JA. p. |Hb. |Oak |Larch
Sp.
Ref. 0.0%] 0.2%] 0.0%] 0.0%] 0.0%] 0.0% | 0.0%
Rob. [92.7% 1.9%] 0.3%] 0.0%] 0.4% | 14% | 0.0%
Beech | 1.8%] 73.0% 0.2%] 0.0%12.8% [31.3% | 0.5%
Sc. p. -| 0.0%] 0.0%] 55.6%) 13.0%] 0.0% | 0.0% [12.5%
Sp.
A. p. 0.0%|_0.0%|22.0% | 79.7%| 0.0% | 0.2% | 3.0%
Hb. 0.0%| 12.6%| 0.0%| 0.0% |85.7%|10.0% | 0.0%
Oak 5.5%| 11.1%| 0.2%| 0.0%| 1.1% |55.4%| 1.5%
Larch | _0.0%| 1.3%|218%| 7.4%| 0.0% | 18% |82.5%
Table 6: The error matrix of ‘maximum likelihood empirical’
classifier.
Rob. (Beech |Sc.p.-|A.p. |Hb. |Oak [Larch
Sp.
Ref. 0.0%] 0.0%| 0.0%] 0.0%] 0.0%| 0.0%] 0.0%
Rob. [82.7%] 9.0%] 0.0%] 0.0%] 3.8%] 33.0%| 0.0%
Beech | 5.5%(54.4%)| 0.1%] 0.0%] 9.1%] 24.1%| 0.0%
Sc. p. -| 0.0%| 0.0%|60.6%| 24.3%| 0.0%| 0.0%] 20.5%
A. p. 0.0%] 0.0%] 21.9%|67.8%)| 0.0%| 0.0%| 0.0%
Hb. 0.0%] 13.2%| 0.0%] 0.0%|86.8%| 7.1%| 0.0%
Oak 11.8%] 22.6%] 0.1%] 0.0%] 0.4%|34.5%| 1.5%
Larch | 0.0%| 0.8%] 17.2%] 7.9%| 0.0%| 1.3%|78.0%
Table 7: The error matrix of ‘minimum distance’ classifier.
Rob. |Beech |Sc. p. -JA. p. |Hb. |Oak [Larch
Sp.
Ref. 0.0%|_0.2%| 15%|_0.0%| 0.0%| 0.1%| 0.0%
Rob. _189.7%| 1.5%| 0.0%| 0.0%| 0.4%| 1.1%| 0.0%
Beech | 1.5%|63.6%| 0.1%| 0.0%| 13.2%| 48.6%| 0.0%
Sc. p. -| 0.0%| 0.0%|49.9%| 9.0%| 0.0%| 0.0%| 18.5%
Sp.
À. p. 0.0%| 0.0%] 29.1%|83.6%)| 0.0%| 0.0%| 2.0%
Hb. 0.0%] 13.0%] 0.0%] 0.096|86.09/6| 11.6%| 0.0%
Oak 8.8%] 20.9%] 0.3%| 0.0%| 0.4%|36.5%| 2.0%
Larch | 0.0%] 0.8%] 19.1%] 7.3%| 0.0%] 2.2%|77.5%
Table 8: The error matrix of ‘maximum likelihood’ classifier.
The main advantage of this method is to separate classes, which
do not have a normal distribution. The distribution of a lot of
Intemational Archives of Photogrammetry and Remote Sensing. Vol. XXXII, Part 7, Budapest, 1998
vegetation classes are two-peak featured, and the conventional
maximum likelihood classifier is unusable for (Figure 9).
frequency /
probability
>
T T T T T T T T T de
58 60 62 64 66 68 70 72 74 76 Band IV.
Figure 9: The distributions of two forest classes.
6.3 Classification of SPOT Pan
The correlation between the SPOT P and the DTM was studied
at first, and was found insignificant, so topographic
normalisation (I mean radiometric) wasn't applied. Then a lot of
classification procedures were tried with the image. A good and
very simple method is a reclassification of the original image
with two classes. The wooded areas are up to 63 brightness
numbers, and the brighter (64-255) is non forested. The accuracy
of this classification method is 94.3 % for this test area, and
about 3 % of the error are the water surfaces. Finally three forest
classes were separated with this reclassification of the forested
area. It was astonishing, that the coniferous and deciduous stands
were not separable on the grounds of the SPOT P, but the
brightness numbers of the image correlate with the age and the
crown closure (Table 10), but almost impossible to determine the
characteristics of the classes.
Correlation coefficient (r)
Age 0.68
Crown closure 0.56
Table 10: The correlation between the stands' age, crown closure
and SPOT P brightness numbers.
6.4 Classification of Brovey-transformed Landsat TM and
SPOT Pan
The Brovey-transformed Landsat and SPOT image was not used
for forest stand classification purposes, because there were some
problems from the different date. There were big clear felling in
the four-year period (‘91-‘95) because of the great woodborer
disasters. The changes are easily demonstrable, but hard to
interpret in the forest stand classification. I tried to apply an edge
detection for the boundaries of stands. An edge-preserving-
smoothing was the first step. Then an edge-detector filter and a
segmentation method was applied (Narendra, Goldberg, 1980).
The best result was showed by the band VI. (!!!), but only the
major roads were extractable.
367