DIGITAL PHOTOGRAMMETRY AT GRADUATED STUDY IN UACEG 
at c : b . : 
N. P. Draganova ^ , G. E. Hristova ', B. D. Marinov © 
UACEG, Faculty of Geodesy, bul. Hristo Smirnenski 1, 1046 Sofia, Bulgaria 
(“ petrova_npd@yahoo.com , ° gergi@gbg.bg , * marinovb_fgs@uacg.bg ) 
Commission VI, WG VI/1 
KEY WORDS: Digital Photogrammetry, Education, Training, Urban Mapping, Close Range Photogrammetry 
ABSTRACT: 
The education in Digital Photogrammetry is very important for the modern photogrammetry teaching courses, Different approaches, 
used methods and products are discussed. The main goals of educational process in Digital Photogrammetry are defined. The 
arbitrary digital systems are mentioned with the examples in the field of terrestrial, aerial and space photogrammetry. The main 
attention is paid to the systems of middle class. The implementation of main processing stages in Digital Photogrammetric systems 
for stereo plotting and orthorectification is discussed. The degrees of automation of different steps of measurements are compared in 
sense of automatic and semi automatic measurements. The special emphasis is made on the possibilities for education and training in 
the measurements of fiducial marks, tie points and control points. The comparison between monoscopic and stereoscopic methods 
for measurements is made based on the examples from PCI Geomatics and Leica Digital Video plotter. The application areas and 
possible technologies are introduced for purposes of urban cadastre and agricultural territories mapping. The two possible 
technologies for 2D digitising of orthophoto and for 3D stereo plotting are compared. 
The integration of functionality of systems for Digital Photogrammetry and Digital Image Processing for Close Range 
Photogrammetry is demonstrated too. The adopted methodology is applied for archiving of architectural monuments. There are 
shown the experiments with images of wall paintings in the ancient church of Dragalevci monastery “The Assumption of the Virgin 
Mary”. The geometric and photometric problems that arise in mosaicking of multiple images, taken from short distance due to the 
small size of interior spaces, are solved. A two-stage procedure of image rectification is suggested for processing the transformation 
of such images. The sub-images of mosaic are tied and transformed to vector model before and after mosaicking. This procedure is 
corresponding to usage of finite elements methods for geometric transformation. Direct application of finite elements method is not 
possible to be used every time if there are not enough features in the images to create narrow net of points. The equalization of 
radiometric characteristics of mosaic images is made based on the histogram distribution of their overlapping parts. The suggested 
technology is suitable for production of adequate photo model for archiving of architectural monuments and virtual reality modelling 
(VRML). 
The experimented technologies for cadastral registration and monuments archiving are implemented in the regular course of study. 
The implementations of interactive learning methods and user controlled training systems (for the basic photogrammetric operations) 
are suggested that will ensure future improvement of the quality of educational process. 
1. INTRODUCTION The universal digital photogrammetric systems can be used for 
practical demonstrations and training. They can cover 
The education in digital photogrammetry is very important for fundamental problems of two main photogrammetric 
the modern photogrammetry. Digital technologies are widely technologies, which are implemented in digital form - 
used now and replace the traditional photogrammetric methods. orthophoto production and 3-D digitising. Almost all digital 
Digital image processing was initially used for space images but photogrammetric systems support these two technologies. But 
at present days it is used for processing in aerial and close range the degree of automation and the adaptation of the systems are 
photogrammetry. Considering these reasons the teaching and different. 
training of students in the field of digital photogrammetry is 
very important. There exist different methods for interactive The preparation of learning kit, which main objective is the 
teaching based on computer technologies. Some of these creation of an interactive guide that furnishes both operative 
approaches are appropriate for education in photogrammetry ^ information and theoretical elements of digital photogrammetric 
too. The digital photogrammetry is very convenient field restitution is presented in (Albery, E., A. Lingua, P. Maschio, 
because it is based on computer processing of photogrammetric 2000). The interactive guide is divided into modules, which 
images. The traditional way of teaching is based on presenting supply both operative information and theoretic elements to 
the information on theoretical and practical topics of photogrammetric processes. It allows the interactive leaning at 
educational subject. The information is presented in written or three levels of experience. 
oral form. The modern presentation is based on slide 
demonstration by projector or by computer supported The development of a modular educational system for digital 
presentation. Another way for obtaining of this information is photogrammetry is described in (Ireneusz, E., B. Roland, etc., 
through Internet in the form of E-learning materials. They are 2000). 
arranged as static or more or less dynamic pages. 
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