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2. INFORMATION TECHNOLOGIES AND THEIR
INTEGRATIONS
The rapid development of information technology at the end of
the last century has led to the realization that without the
application of modern techniques in archaeology and
conservation it is not possible to keep up to date of the
demanding documentation processes which are directly
connected with an increasingly demanding research
methodology and with the documentation itself. As part of
many methods of recording of culture heritage were
photogrammetry is one of the techniques of data acquisition,
which has successfully established itself in conservation and
archaeology over the last hundred years. On archaeology the
photogrammetric method of documentation is predominantly
connected with rescue excavation or recording of standing
structures, since this method of documentation is seen as the
only one to guarantee the reliability and accuracy of the actual
condition. In the past the process of excavation was directly
dependent on the execution and speed of the photogrammetric
shooting, the stereophotography, development time and the
ability of the team. Because of the limitations mentioned above
the excavation process often had to adapt itself to the shooting
of stereo pairs, the photogrametrist was not always rationally
exploited, while a laboratory for the production of photo
sketches was not always available, which slowed the progress
of the excavation. Manipulation is fast and very important in
the archaeological interpretation of the site. Another important
advantage of this method of photogrammetric recording is the
speed of data acquisition and instant processing. Documentation
of this type in digital form is also essential in the drawing -up
of conservation programmers, which in the final phase lead to
various presentation decisions, and for the preparation of
various models of visualizations, design of modern structure
shelters or coverings. The comparison showed that significant
differences exist in the accuracy of photographs of the same
architectural remains, and above all that we can understand
archaeological or architectural drawing as a phase of
preliminary interpretation. Preliminary interpretation, if not
done together with photogrammetric documentation, is not a
true representation of the actual condition, and since the
documentation is also created for the future, only a document,
which shows the true condition, is credible (Stokin, 2002).
3. PRINCIPLES OF ARCHITECTURAL
PHOTOGRAMMETRY
For many purposes detailed plans of existing buildings are
required. Especially for the preservation of architectural
monuments a great variety of data about the facades and the
structures is needed for documentation purposes and for
planning of further activities, especially by CAD methods. If
the original plans are not available or if the facade has been
changed the only way to acquire this data is the survey of the
buildings surface. This can be achieved either by direct
measurements using scaffolding or indirectly by
photogrammetric approaches.
The basic idea of architectural photogrammetry is to reconstruct
the imaging geometry, which was effective during the exposure
of photographs in order to derive object coordinates. However,
the three dimensions of the object are reduced in the photograph
to a two-dimensional image space. This is why three-
dimensional object coordinates cannot be derived from one
image. Photogrammetry therefore combines information from
two appropriate images to survey a three-dimensional object.
The photogrammetric approach offers several significant
advantages compared to classical surveying methods. Field
operations are reduced to the acquisition of photographs and the
measurement of a few control points. In this way a tremendous
amount of information is permanently stored in the
photographic film, surpass sing each construction plan or
drawing. Any detail of a building, which is photographed in at
least two images, can be subject to photogrammetric restitution.
This procedure can be carried out at any time and at any place
independently from the object. Modern photogrammetry can
effectively provide metric data of high and homogenous quality
from existing buildings for CAD purposes (Albert, J.,
Wiedemann, A., 1995).
4. PHOTOGRAMMETRY AND GIS
The use of new techniques and an interdisciplinary approach
offer a wide data base and thus make it possible to make more
reliable interpretation of the results, which are an integral part
of the conservation project. The integration of photogrammetric
and geographic analyses through the employment of computer
documentation system permits precise documentation, rapid
access to data and elaboration with new methods.
Since the development of the science of photogrammetry, there
have been many applications of its techniques and technology
in the recording and documentation of monuments and sites of
importance. Whilst there may have been a redirection of effort
when aerial mapping expanded following the invention of
aircraft, there has been a shift again to other measurement
applications offered by photogrammetry, especially those in
architecture and archaeology. Developments in the sciences of
photogrammetry and image processing over the past decade or
so have seen an increase in the automation of the data collection
process, ranging from high precision industrial applications
through to simple solutions for non traditional users (for
example, 3D builder and PhotoModeler). In addition systems
that use imagery from consumer digital and analogue video
systems and sequences of images have almost automated the
creation of 3D models (as has the development of 3D laser
scanners)(Ogleby, 1999).
Photogrammetry is a technique whereby information about the
position, size and shape can be attained. Photogrammetric
products refer almost exclusively to the object space (maps,
surfaces (DEM’s), orthophotos, points, profiles).
Photogrammetry is an important contribution to many
disciplines. The most widespread use of the photogrammetric
technique being for the representation of the facades or
elevations of building and structures. There are many uses of
the technique, including 3D city models for building repair and
conservation. The 3D reconstruction of houses and other man
made objects is currently undergoing active research, and is an
issue of high importance to many users of GIS, including urban
planners, architects, telecommunication and environmental
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