yy Advances 
ms. Progress in 
etween systems 
y are ceasing to 
gen im Bereich 
nd die Basis für 
geographische 
erwischen. Wir 
three business 
] workshop on 
ic Information 
rith the ‘Second 
for Marine and 
ticipants from 
rorkshop which 
tel on February 
on a variety of 
nges faced by 
rk in Belgium, 
y, Norway, and 
Jed functional 
sing GIS; the 
echniques such 
ind numerical 
se of temporal 
and challenges 
countries; and 
Jlications. 
rporations also 
n, which was a 
poster session 
  
was also held, at which seven posters were presented on 
diverse areas of application. Proceedings for the 
workshop will be published later this year (Ehlers, et al., 
1994). 
Another workshop on 'Visualization and GIS' is 
tentatively scheduled for May of 1995 in Germany. 
20 SYSTEMS TECHNOLOGY ADVANCES 
A critical review of the systems aspect for the processing 
of geographic data reveals that progress in this area has 
been primarily driven by advances in technology. These 
advances come from fields remote sensing, 
photogrammetry, surveying, or mapping. 
In particular, progress in computer science and the major 
acceptance of geographic information systems (GIS) as a 
unifying technology are challenging the "separation of 
disciplines". Consequently, the shift toward integrated 
systems for processing of geoinformation is driven by 
advances outside the disciplines traditionally represented 
by ISPRS. It is, however, imperative that ISPRS 
responds to these technological challenges. 
We need an integrated approach for research, 
development, and education in geoinformation processing 
which might be coined "geoinformatics". If we do not 
aggressively adopt such an integration, photogrammetry 
and remote sensing might end up as minor subareas 
within computer science and informatics. 
In the following sections we will try to summarize 
advances in hardware and software which generally apply 
to all systems involved in geoinformation processing. 
2.1 Hardware Advances 
11.1 Computational Power. The advances in 
speed and power of computers have been phenomenal. 
Processor speed has approximately doubled every year 
since 1986. General purpose RISC processors are 
available with speeds in the range between 25 and 100 
MIPS (million instructions per second). Graphics and 
image processing computers running at 300 MIPS (e.g. 
Vitec or Silicon Graphics) are available. These computers 
are programmable and can be used for a wide variety of 
tasks (Faust, et al., 1991a). 
Concurrent with advances in the workstation or 
minicomputer processing power, advances are being 
realized in the PC class. The Intel 80486 and Pentium 
and the Motorola 68040 and PowerPC chip are providing 
the power to do tasks which have been traditionally 
reserved for mini or mainframe computers. 
Almost all general purpose computers have been, until 
recently, single CPU computers. The availability of 
multi-processor machines is becoming more common. 
There are already several machines on the market such as 
the NCUBE/10, Sun Sparc10 and others. 
These increases in power in off-the-shelf hardware mean 
that is no longer necessary to design and build single 
purpose image processing or geographic information 
systems. The days of the dedicated image processing 
station are rapidly disappearing. 
2.1.2 Scanning Technology. Scanning is a widely 
accepted technique for the input data into a 
geoinformation processing system. It is often used to 
input map data from hardcopy to a GIS. Due to the 
unfortunate lack of operational digital aerial cameras, it is 
also the most common approach to acquiring data for a 
digital photogrammetric system. In order to achieve the 
resolution of an analog photo in a digital image, it must 
be scanned at approx. 10mm (2500 dpi) (Ehlers, 1991). 
While there are a number of scanners available which are 
capable of such resolutions (i.e. Zeiss Photoscan, HAI 
100, Vexel), they are quite expensive. 
For many applications, however, it is not necessary to 
have a digital product with the full resolution of an aerial 
photo. The field of desktop publishing has, to a large 
degree, driven most of the recent advances in desktop 
scanning. Users in this field have demanded, and received, 
higher resolution, color capability and lower cost. 
Manufacturers are now offering scanners that offer 
resolutions of 600 or 1200 dpi in format sizes suitable 
for scanning aerial photos which are as much as an order 
of magnitude cheaper than those offered specifically for 
photogrammetric use. For applications not requiring full 
photographic resolution, the results obtainable from 
desktop scanners offer suitable resolution and accuracy 
(Sarjakowski and Lammi, 1991). 
2.1.3 Storage Capacity. The analysis of geographic 
data requires the storage of large amounts of data. 
Advances in disk drive and other mass storage technology 
have kept up with those in the processor field. 
We have progressed from a point where 50 MB of hard 
disk storage required a cubic meter or more to being able 
to store 1.2 GB on a 3-1/2" hard drive that occupies 
about 0.2 cubic meters (in external configurations). The 
form factor for hard drives continues to decrease along 
with the increase in capacity. 3-1/2", 500 MB drives are 
common and smaller drives are being developed and 
introduced. 
Other forms of magnetic media have also advanced. The 
3-1/2", 1.2 or 1.4 MB floppy is the defacto standard. 
Magnetic tape systems such as the Exabyte are capable of 
storing 5 GB of data on a cartridge (with compression) 
that is roughly the size of an audio cassette. 
Optical or magneto-optical (M-O) storage is further 
increasing storage capacity. CD-ROM and WORM 
(Write Once, Read Many) drives are commonly used for 
archiving data. M-O systems with read/write capabilities 
currently store 650 MB per disk and, with foreseen 
technical advances, this is expected to increase to 10 GB 
within the next 5 years. When coupled with juke box 
mechanism, users will have access to 100's of gigabytes 
377