ta. In
essary
ations.
aerial
andard
rsonal
nce of
paper.
digital
r- und
ischen
1g auf
ntypen
1- und
e- und
ig und
> neue
lb der
rrektur
al data
ormats
graphs
alings.
(js and
| data
itioned
angles
Image
py two
) scale
remote
00 and
restrial
20. For
jraphic
flatbed
er data
restrial
zed or
stration
Both data types have to be displayed and edited by the
visualization and measuring software.
1.2 Education Goal
Digital photogrammetric methods require knowledge of
the image data sets, the annotation data and all
necessary algorithms to produce the digital output.
Therefore the candidates or students have to learn how
digital data sets have to be processed in order to reach
“ good quality and accuracy in the processing results.
This is shown by digitized aerial photographs, satellite
images and digitized maps. Additional ground control
points are calculated with location in image coordinates
and geographic or cartographic coordinates.
The dependencies between high and low resolution,
necessary high and low data storage requirements and
the resulting accuracy will be outlined in the lectures and
exercises.
To enable follow on training all image processing steps
will be shown on PC-based systems under MS-Windows.
1.3 Experience after completion of Training
After training with typical photogrammetric examples the
students should possess experience in following areas:
e conversion of image formats,
e image transfer between different hardware and
software systems,
e application of flatbed scanners and digitizers or
onscreen digitizing tools,
e application of rectification programs,
e application of image enhancement methods,
e calculation of geocoded or georeferenced digital
image data sets,
e data fusion results for later data integration
applications.
2. HARDWARE AND SOFTWARE EQUIPMENT
In addition to the well known analog and analytical
photogrammetric equipments the computer software and
hardware plays a growing role at IPI. To fulfill educational
and research requirements additional individual software
for image processing and adjustment has been
developed in the past.
2.1 Hardware Requirements
Until 1988 operational image processing systems have
been implemented on VAX (VMS) mini computers and
SUN (UNIX) workstations. Depending on research
projects additional individual software has been
developed on both platforms. To enlarge the students’
acceptance of image processing tools it was very
important to integrate new functions also on personal
computers.
Therefore a large number of modules has been converted
to C-language operating under MS-DOS and MS-
Windows since 1985.
139
Today powerful PENTIUM PCs with two or three Gbyte
disc storage are installed. But most of the students work
under following hardware conditions:
CPU 486/66 Mhz,
500 Mbyte disc,
16 Mbyte RAM,
1,44 Mbyte floppy disc,
CD-ROM
Mouse,
Ink-Jet Printer,
15" or 17* color monitor.
Of course there are always new hardware modules with
more powerful CPUs and better peripherals, but for
educational purposes a running system under above
mentioned conditions is more recommended because a
running stable system is much better than a state of the
art system with unknown bugs and internal problems
which prevents the user from working.
Additional peripheral devices are necessary to enable
data exchange, image processing and digital video
applications:
Ethernet board,
SCSI Interface and Flatbed scanner,
backup streamer tapes,
digitizer or digitizing pad,
graphic board with variable resolution (480x640 up
to 768x1024 pix) in 256 colors (32768 or 65535),
e frame grabber board.
2.2 Software requirements
For operational purposes or industrial applications a lot of
very powerful but also expensive software systems are
installed. Tools like ERDAS, EASY/PACE, MGE or for
example IDL/ENVI are well known in the areas of remote
sensing, image processing and digital photogrammetry.
For education and training very often low costs systems
are preferred. Therefore public domain tools like
KHOROS or GRASS are installed at the Institute. In
addition standard PC-based software in combination with
individual software is used at IPI, Hannover.
To enable analog to digital conversion of photographs
and maps scanning software is required. For this purpose
the scanning software of the HP Scanjet llcx is sufficient.
On PCs this software is accomplished by drawing and
low-level image processing software like ALDUS-
Photostyler or Photoshop. To meet all requirements of
education and training contents additional individual
software has been developed at the Institute. The
modules enable following processing steps:
e image format conversion, digital filtering,
e geometric correction,
e onscreen digitizing,
e mosaicing.
To connect ARISTO or Summagraphics Digitizers
standard software as well as individual drivers are used.
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B6. Vienna 1996