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CONSEQUENCES OF THE PHOTOGRAMMETRICAL VIEW OF SOLVING SPECIAL 
TASKS IN DIGITAL PHOTOGRAMMETRY WITH SERIAL COMPUTERS 
DR. ERHARD PROSS 
Research Centr of Geodesy and Cartography 
Karl-Rothe-Str. 10 - 14, Leipzig, DDR-7022, G. D. R. 
1. Development of image structures 
Photogrammetric methods use information in the form of two-dimensional 
representations of facts. In connection with map production and generation 
of topographic and other thematic information, respectively, part of the 
Earth's surface is imaged at the same time. 
While during the last years mainly photographic images - i. e. analogue 
representations - had been used, recently digital representations in the 
form of so-called digital images gained in importance. This process was 
influenced by the increased employment of digital computers as well as 
digital image processing. 
Figure 1 shows the methodical development from analogue over differential 
and analytical to digital. This reflects - as typical in photogrammetry - 
in respective technical devices. 
From the point of view of discretization of data, firstly the plane co-ordi 
nates are discretized (differential - one, analytical - two), but then the 
grey value range too (digital - three). The last transition corresponds to 
a qualitative jump, because the traditional analysis is not sufficient for 
the mathematical model, but functional analytical methods have to be applied 
(see also /1/). This means inter alia, that data and processes basically 
have to be remodelled in an uniform calculation, whereby analogue, differen 
tial and analytical methods are naturally imbedding (/1/).