48
Ae BEST = sautomatio differential reotifijoation with.a
simplified program
In addition to the TOPAS program package which calculates
control data for the differential rectification process
from digital height models with arbitrary point arrange-
ment, a simple program has been developed which processes
the profile data obtained from on-line differential reèti-
fication with digital control unit. Ths BEST program is
written in FORTRAN IV and elaborated for minicomputer with
64 kbyte main storage capacity.
The BEST minicomputer program allows the utilization of
the off-line differential rectification (cross-slope cor-
rection, double model orthophoto production, repetitive
rectification) in a simplified process, which is based
on the TCPCCART/ORTHCPHOT system combination with digital
control and cross slope correction, Input data are used
which are recorded with the digital control unit in the
output mode on data carriers in order to calculate control
data for the off-line rectification process. The control
data calculated with BEST have the same record format as
the control records calculated with TOPAS (three-digit
smoothed model height data: three-digit tangent data in-
formation on the terrain cross slope).
IRTHOPHOT D-300 offers the possibility to limit the length
of each profile individually by a button so as to rectify
only those parts of the model being of interest, for
instance, for routes or map revisions.
Therefore, the BEST program can also handle profiles of
different lengths. If for one profile point only one or no
neighbouring point at all is found by this, the calculation
of the terrain cross slope is performed by simplified for-
mulas and model smoothing is dispensed with.
Differential rectifications performed with cross slope cor-
rector result not only in a better image quality through the
elimination of systematic errors but have also the essen-
tial advantage that they can be carried out with at least
the double slit width as compared to differential rectifi-
cations without cross slope correction, Às is evident,
this way Of rectification benefits the economy of ortho=
photo production quite eonsiderably, Furthermore, control
data for the same model area and the same model scale can
be used as often as is desired, so that a special data bank
with files is generated for the particular map sheets.
The BEST program belongs io the standard equipment of the
digital control unit.
Deferences
(1 Marekwardt, W.: "Application and accuracy of the TOPOMAT
automatic restitution system", Presented Paper XIIIth ISP-
Congress, Helsinki 1976, Commission II and Kompendium
Photogrammetrie Vol. XIII (4979) p. 424
Bürger, M.; Illhardt, E.: "Accuracy and reliability of
the fully automatic TOPOMAT A photogrammetric restitution
system", Surveying News 1980/1 pp. 21-23
——J
Ur
PO