Fig. 1 Combined image of an orthoimage and
cartographic data
that presents the real object’s situation (ortho image) combined
with the cartographic (vector data) that has been derived from
the digitization of a classic map (fig. 2).
The video file is very impressive and can be used for several
reasons to enhance the usability of a map. It provides a new
perspective for the use of cartographic data.
The path that the virtual camera will follow to capture the
image sequence of the video can be constructed very easily
43 Windows Media Player
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using CAD-CAM techniques. However, the design of the
camera path characterizes the use of the map since its creator
can emphasize on some specific parts of the map. The path may
follow a straight line, always facing in front and fly over the
objects draped model, or it may follow a circular line and
concentrate on a specific target point of the map, (ie. the
capital of the prefecture that is imaged on the map).
4. APPLICABILITY
In our case the map that has been created illustrates the port, the
capital and some of the monasteries of the Mt. Athos in Greece.
Many fly over paths have been created emphasizing different
parts of the map. In fig.3 the configuration of the camera's fly-
over path is shown. The path follows a spiral line and the target
point that the camera is always concentrated on, is the center of
the map. This video file may be used for a virtual tour of a
potential visitor over the Mt. Athos. The user of the video may
also observe the distances between the monasteries and may
also examine the difficulties that he will find during his future
realistic visit.
A very important aspect of the video file is the fact, that the
objects’ scale mapped on the video is variable. Since the
camera starts moving from a point far away of the objects and is
approaching closer to them, the images of the video sequence
browse these objects in greater scale as time passes. The non
uniformity of a map’s scale, has been used before to emphasize
some specific parts of the map’s region (Boutoura, Ch., et. al.
1999).
In most of the cases a map is presenting the imaged object from
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Fig. 2. Using the Windows Media player the user can browse the video file of the virtual fly-over the map
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