Fernerkundung I (Digitale Bildverarbeitung) - Friedrich-Schiller ...

fn = in_dir + $Z + dirlist[i]
ext = getfileextension(fn)
bn = getfilebasename(fn)
if (ext ~= "pix") then
MONITOR = "ON"
file=in_dir + $Z + dirlist[i]
!starting with DAS routine
dbsl=number
RUN DAS
endif
endfor
endif
print "Finished all"
! this is just a simple example of a batch routine using if-then-endif and for-loops
! and asking the user to enter some parameters
Abb 4: Beispiel EASI Routine: EASI Routine zum Löschen von Segmenten oder Kanälen
in allen PIX Dateien in einem Verzeichnis.
Further Reading: see “EASI Users Guide”.
3.6 GCPWorks
This section has been created partly from the GCPWorks Manual in the Geomatica
documentation.
GCPWorks only deals with non-systematic errors, which include those due mostly to the
variations in altitude and attitude (roll, pitch, and yaw) of the sensor platform at the time
the data is acquired. Measurement techniques to correct these errors involve the
collection of ground control points (GCPs) distributed evenly over the whole image. The
best GCPs are located at well-defined and easy to recognize points on both the
georeferenced (being registered to) and uncorrected (being registered) data sets. The
displacements of these GCPs between the uncorrected and georeferenced data sets are
used in the correction of these errors. A least squares regression analysis is used to
determine the coefficients for twocoordinate transformation equations which relate the
distorted image to the desired true map projection.
The geometric correction is carried out in a two-step process:
1. Transformation of Pixel Coordinates: Each pixel in the target or georeferenced image
is transformed according to the warping polynomial to determine a sampling location in
the input or uncorrected image.
2. Resampling: Resampling is used to determine the pixel values to fill into the
georeferenced (output) image from the uncorrected (input) image.