din
ori
icated
hat a
From
je se-
dency
for the
> the
consid-
This
a the
annels
ctions
t is
a modi-
(T)
This quantity considers only the sign of the residuals, how-
ever not their possible dependency on the position or type
of the scanned object. The establishment of a corresponding
functional model would have requested an unreasonably high
expenditure. In addition, it seems to be very questionable
whether or not the different topographic objects, which for
the linear dependency does not apply, could have been de-
scribed with satisfying accuracy by a single function. In-
stead of this, the residuals inserted in the test mentioned
above produce a new image with the density values G1, G2,
and G3 obtained from the following decision rule:
if
tv, > + b etimol» then v, results in G1 = 255
(A full blackening)
- NL s 1; € by Im |, then v, results in G2 = 128
(A medium density) (8)
ev t sols then v. results in 05 - ©
(^ white),
whereby t was set to 1.0; 0.5 and 0.1. (With ts 3.30 for
a statistical certainty of 99.9% only clouds were represent-
ed.) Figures 2 - 7 show the results.
The decreasing t,-values effect that the indifferent areal
elements primarily with [e = 1.0 in medium density become
cither white or black pixels, thus resulting in noisy or
linearly or arealike structurized images. The selected exam-
ple demonstrates that not all four channel combinations of
the areas 1 and 2 produce noisy images, as could have been
expected from Table 2, but only the combinations of the chan-
nels 4 and 5. This yields result 2:
Two spectral data sets depend linearly on each other only,
if the selected functional model fits, whereby mo attains
the magnitude of the digitizing errors conditioned by the
System. Due to the fact that the pixels computed from the
residuals according to equation (8) are independent of their