Appendix A. The method of Matsumoto's[1991]
to decompose mixed data; The Maximum
Likelihood Estimation
The spectral reflectance(I) of K bands
from the mixel which contains of H landcover
categories is expressed like the Eq. 1; it is
the multiplication of the mean vector(M) of
the spectral reflectance from the pure pixels
of each landcover category and the mixture
ratios(A) of landcovers in the mixel.
Yor VA Arkaden Abk Anbieter Eq.1
where,
I=(1 1 Sw... In)
t
Asa rag Pin 8 )
My7 M12 ++ 0000000 mig
M==1"""" qp EN
9922229222292
Mxri Mxrz2 00000000 0° Mxyu
Now, suppose the reflectance(Iij)of the
band (i) on the landcover category (j) has a
normal distribution with mean M*ij and
variance (2. Then, the mean vector (Mi) of
the spectral reflectance of the band (i) is
expressed like Eq.3. The variance of the
spectral reflectance is expressed like Eq.4.
INA, =— IM >= Z7
à a. TTT dT m um m MN UN NN m m man Eq.3
: + + * *
2 dz
o°.= * S. *
PEE Trees =
. 2 2 2
S diag(04 ,0, , «eie en)
Then, the likelihood;P(Ii), which the
reflectance data of the band. i may be
observed, is expressed like the Eq. 5.
Supposing that the spectral reflectance is
independent among bands, the total likelihood;
P(I), which the spectral reflectance
Ii,I2,....,IK may be observed, is expressed
like Eq. 6 and 7.
_ exp = (IM) Trey)
o,*4 (2m)
P(I,) ----Bq.5
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B3. Vienna 1996
N
P(I)-II P(ri) dide 6
i=1
O — — In { P(I) ) T----Eq.7
k
Yiu aL) Pare 0 | (hep, 0%. fie)
j=1
EG
Note:
H: Number of landcovers
K: Number of bands of image data
i: Band No. (1 to H)
j: Landcover ID.
ai: Area ratio of landcover[h] in the IFOV
of pixel[i,j] (unit: IFOV)
The mixture ratios of landcovers in a
mixel can be computed by obtaining A, which
minimizes @ under the conditon which
expressed in the Eq.8. This is the method to
decompose mixed data using the Maximum
Likelihood Estimation developed by Matsumoto
in 1990.