The Digital Photogrammetric Station at the ETH Zurich 
Armin W. Gruen 
Institute of Geodesy and Photogrammetry 
Swiss Federal Institute of Technology 
ETH-Hoenggerberg 
CH-8093 Zurich, Switzerland 
"The engineering problems in electronic 
photogrammetry are very considerable .... It 
will be a long time before completely 
automatic, electronic photogrammetry is 
actually at hand." P. Rosenberg, 1955 
Abstract 
The Institute of Geodesy and Photogrammetry at the Swiss Federal Institute of Technology, 
Zurich, Switzerland, has acquired a new system for research and development in digital and real-time 
photogrammetry, the Digital Photogrammetric Station (DIPS). This paper describes the system's 
hardware configuration, some of the extensions and improvements which are planned for the near 
future, and the ongoing and proposed research and development activities. 
1. Introduction 
The fully automated map compilation process has been on the mind of photogrammetrists for 
many years. An automatic data acquisition/processing system for orthophoto generation was 
perceived and designed as early as in the fifties (Rosenberg 1955, Williams, Rosenberg 1956). 
Rosenberg's system included TV-aircraft scanners with frame scan, single line scan, and spot scan 
versions, a fully automatic analog correlation device, a photo printer and a CRT display for interactive, 
operator controlled map manuscript production. As anticipated by Rosenberg, automation showed 
some early success in relief measurement and orthophoto production. However, the most fascinating 
problem in Rosenberg's system, the extraction and recognition of planimetric features, is still the 
major problem of today's systems. 
Today digital components have partially replaced the analog "electronic" devices, allowing for 
faster development and for a more flexible system utilization. Recent advancements in 
semiconductor technology and microelectronics are key factors in the rapid current development of 
new photogrammetric data acquisition and data processing equipment. Digital sensor technology and 
digital processing systems have been available for quite a while, but only recently have their 
capabilities improved so tremendously and their costs dropped so significantly that these systems 
are becoming affordable to an ever increasing customer group. In addition, the rosy prospects of 
finding many new applications and progress in data processing methods have further stimulated their 
development and use. Predictions claim a compound annual growth rate of machine vision systems 
of about 50% until 1994 (Tech Tran Corporation 1985 p. 178 ff.). This would result in an installed 
base of nearly 200,000 systems by the mid-1990's. The projected number of annual sales of 
complete units in 1994 would be 64,000, which would correspond to a sales revenue of US $ 1,200 
million. 
Although Analytical Plotters are just at the edge of general acceptance in the professional practice 
and their capabilities not fully utilized yet, a new category of processing equipment, the "Digital 
Plotter" is starting to have a severe impact on research projects and development strategies of 
governmental and privat R & D facilities. 
. Some conceptual ideas and initial experiments with respect to Digital Plotters can be found in 
Albertz, Koenig 1984, Case 1982, Dowman 1984, Jaksic 1984, Kunji 1985, Sarjakoski 1981. At the 
Institute of Geodesy and Photogrammetry at the Swiss Federal Institute of Technology (ETH), Zurich 
the author has recently acquired a new system for research and development in digital and real-time 
photogrammetry, the Digital Photogrammetric Station (DIPS). The base system consists of a host 
computer, an image processing system, a workstation, two CCD cameras, and software components 
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