CCD MULTICAMERAS INTERACTIVE DIGITAL SYSTEM 
FOR CLOSE RANGE PHOTOGRAMMETRIC APPLICATIONS 
Piotr Sawicki * Boguslaw Wiecek * * 
* Chair of Photogrammetry and Remote Sensing 
Olsztyn University of Agriculture and Technology 
PL 10-957 Olsztyn, 1 Oczapowskiego Str. 
e-mail: sawicki@moskit.art.olsztyn.pl 
** Institute of Electronics 
Technical University of Lodz 
PL 90-924 Lodz, 18-22 Stefanowskiego Str. 
e-mail: wiecek@j-23.p.lodz.pl 
Commission V, Working Group 2 
KEY WORDS: CCD, Camera, Digital, Hardware, Image, Bundle, System, Close-Range 
ABSTRACT 
In the paper a concept of a digital photogrammetric system based on the low cost CCD cameras and computer of 
PC type is presented. The system is mainly designed for photogrammetric 3D data acquisition of points in object 
space on the basis of digital images. In the proposed solution, low cost CCTV (Closed Circuit Television) - type CCD 
cameras were used. Orginal solution of the problem of digitization of video sequences was applied in the system. It 
was performed by construction of special framme grabber card. The maximum four cameras are linked with the 
computer through a frame grabber which is based on the modern video processor in order to provide enough power 
to compute images in real time. Entire hardware is managed by the software working as application in MS 
WINDOWS enviroment. The integrated management and photogrammetric software is briefly discussed to present 
the current potentialities of the whole system. Additionally , the most suitable image processing methods for 
contour extraction and quality improvement of visualization of digital images are implemented in the system. First 
experimental results, obtained from the test field studies, determine current and eventual possbilities of application 
of the system in close range photogrammetry - in solving of problems in the field of industrial metrology. Possible 
diretions of further development of the system are also given. 
1. INTRODUCTION e on line systems, working in real-time i.e. in cycle of 
video image recordin (1/25s or 1/30s, according to 
Among the systems that record, process and perform the standard of the vision signal) or near real-time, 
analysis of digital images, a group of photogrammetric e off-line systems, working in interactive mode (they 
digital measuring systems may be distinguished. are often hybrid systems). 
Architecture of these systems is based on electro- ^ Quality of the digital system depends on many factors. 
optical CCD sensors, computer hardware, digital The most significant are the following: characteristics 
processing techniques and on photogrammetric and largess of generated digital data sets, which result 
methods of elaboration. In comparison to other digital from resolution of the electro-optical sensors that were 
video systems, this group of systems is characterized used, applied processing algorithms as well as 
by application of at least two cameras, often structure, parameters and technical possibilities of 
simultaneous recording images as well as by electronics hardware. 
elaboration method based on one of photogrammetric The CCD cameras together with digitizing frame 
functional models. What is more, during elaboration grabber card constitute basic elements in each video 
process, the observations are subject to a classical digital system (Baltasavias, 1990; Gruen, 1988). They 
adjustment as well as to analysis of accuracy and decide about size, resolution as well as geometrical and 
reliability. Applications of the photogrammtric digital radiometric quality of digital images, it means they 
system concern close range recording and deal with, influence significantly on possibilities of practical 
first of all, 3D positioning (optionally also 2D), applications of the system. Power and computational 
reconstruction of engineering object shapes, extraction speed of the host computer,efficiency of software and 
of information from 3D data in the industrial measuring algorithms can improve quality of the primary digital 
techniques. images only in limited degree. 
With regard to the duration time of measuring process Photogrammetric digital measuring systems should 
and processing of the digital data, the photogrammetric characterize themselves with high speed of large digital 
digital measuring systems may be, in general, classified data sets acquisition and processing, high accuracy, 
as follows : functionality and multi-purpose universality of 
512 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B5. Vienna 1996 
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