While exploiting advanced technologies and technical
innovations, it also helps to lay the foundations of a new
form of underwater archaeology, one in which divers
completely cede their places to remotely controlled
devices, given that saturation diving is expensive and
increasingly inappropriate for careful excavations on
deep-water sites. It is our wish that our site, transformed
for the time being into a veritable experimental
laboratory, will permit new technologies to work for the
benefit of historical and archaeological research.
2.2.1 Digital Photogrammetry
The wreck is resting at a depth of 60 meters ; even if
divers are able to go to that depth, the work is very
difficult and potentially dangerous. A diver can not stay
more than about ten minutes at this depth and to establish
a topographic map under those conditions would be near
to impossible. We adopted a light digital photogrammetry
method by using a non-metric digital camera, mounted in
a waterproof housing attached to a bar on COMEX's
submarine Rémora 2000. For a light presentation of the
underwater photogrammetric method you can refer to
[Drap, Long, Durand, Grussenmeyer, 2001-A],
[GrandRibaudF, 2000] and more generally to [cipa-uwp,
2002]
2.2.2 The Photogrammetric Results
A total of two hundred pictures have been oriented, with
a set of rulers to put them in scale and several buoys for
vertical reference. The orientation relative to north is
approximated. More than two thousand points were
recorded and were used to generate a digital terrain
model.
The orientation phase was made with Photomodeler 4.0
and the orientation result were introduced in Arpenteur
for a specific survey of the amphorae.
We develop a special bridge from Photomodeler to
Arpenteur in order to combine the advantage and
specificity of both these software. Photomodeler is
actually more efficient to manage a large set of
photographs and on the other hand we have been
developed a special module for amphora plotting using
data fusion from measure and theoretical model. (see
[Drap, Long, Durand, Grussenmeyer, 2001-A ]).
The main goal was to plot the visible amphorae and
fragment, in order to visualise them in the same time that
we document the site. All the data surveyed are
formalised in XML file which are, in fact, the only result
of the plotting phase. We can parse the XML in order to
generate 3D representation using VRML, PovRay or
MicroStation formalism.
2.3 A DEDICATED DATA MANAGEMENT
SYSTEM
The roots of this project reside in the link between many
tools and the elaboration of this link through a semantic
approach of the objects to be measured and shown.
Measurement, representation, and management are
articulated around a common model formalized from the
« Object » point-of-view and implemented in JAVA 1.4.
Figure 1. VRML site representation, used as an interface to the
archaeological data formalized in the XML result
file
Figure 2. MicroStation site representation, as the VRML one,
the graphic file is automatically generated after the
parse of data formalized in the XML result file
Figure 3. MicroStation site representation. Detail of the last
excavation, we can see the bottom of the wreck
(wood pieces) and several layer of amphora.
The measurement and representation phases take advantage of
this common model by putting in place of a default value
mechanism allowing to take complete measurements of the
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