dinate systan
sat subsence,
transforma-
S by means
he training
e terminal
evels excee=
c picture
e statistics
ard devia-
es of the
jsibility to
cas extracted
0 delete some
"Ce S
the training
sification
represented
rent Super-
fication,
sification.
nd thresholds
file. The
resenting
fied colour
otating drum
ariability of
p an opera-
tain the re-
in this prac-
objective. The
ntioned diffi-
data proces-
n is done by
ystem has
first cluster-
ctral eharac-
group pixels
posed by H.
o consists in
n. Firstly the
which must
es. Then, the
s" is per-
of the regions
2.
nMng-up classifiod images
^ S2
+
The result from à supervised classification and some unsuper-
vised classifications are pixelwise classified image
S using multi-
Spectral information only. This can result in à classified image
having single or isolated pixels with a class assignment that diff-
ers from those of tho surrounding. In many eases, Such detailed in-
formation is not required, instead a generalised classified image
is more useful. Such images may be obtained by comparing the class
assignment of one pixel to its neighbours. The EPDCS system for the
processing of a digital thematic map will eliminate all regions
within an area less than a predefined minimum. Regions which ropre-
sent different features can have different minima.
8. Accuracy evaluation
In order to compare the landsat classified image with ground
truth, we developed this programme which transfer data between image
and map by ground control points, then we can calcul
- ing paramoters!:i
AR. Difference map.
ate the follow-
The map will show the pixels, which have been correctly classi-
fied, by means of an unique symbol. It will also show the pixels,
which have been incorrectly classified, by means of different sym-
bols representing the change of class.
B. Confusion matrix.
The table shows the amount of changed pixels of different class-
es.
C. Over all classification accuracy.
D. Mapping accuracy of every class.
5m. Over all mapping accuracy.
ACKNOWLEDGE
I am very grateful to professor Leit Wastenson, Dr. Walter Arnberg,
Mr. Góran Alm and Miss Laine Boresjo at thé Department of Physical Geography,
University of Stockholm, professor Juri Talts at LMV for their very useful
ideas and experiences.
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