THE WELL PROMISING FLASHPIX IMAGE FORMAT
O. Georgoula, P. Patias
Dept. of Cadastre, Photogrammetry and Cartography, AUTH, Thessaloniki, Greece
olge@topo.auth.gr
patias@topo.auth. gr
Commission V, Working Group V/4
KEYWORDS: image format, photo model, internet, visualization
ABSTRACT
In digital photogrammetry, one of the most common drawbacks, we are facing with, is the manipulation of huge image data. High
resolution images are needed to be mapped on model surfaces (image mapping), in order to have the most of the object details. For a
medium powered computer system, this results in large processing time. Additionally, various presentation methods and effects, like
walk — through paths, add more processing time to the already large one. These problems appear to be common ones in all image
proccessing procedures. The development of the FlashPix format is based on the philosophy that a common user, with a medium
powered computer system, during any image process, should be able to hadle efficiently and effectivly these huge image data sets.
1. INTRODUCTION
Considering the divers types of Information Systems for Cul-
tural Heritage, P. Waldhausl (Waldhausl, P., 1999) hierarchi-
cally mentions:
e a BIS (Building Information System) for a dome, a castle,
a archaeological site, etc. It contains detailed information
about the monument eg. geometrical, photographical, his-
torical, etc
e a MIS (Monument IS), which is the hierarchically next
higher level, it concerns a site, a town, a region etc.. A BIS
may be connected to a MIS. In this case the MIS contains,
in the majority of cases, only meta-data referring to the re-
spective BISs.
e a HIS (Heritage IS), that concerns the heritage of a nation
or even of nations, contains information about all MISs. It
is connected with them and also with the Information Sys-
tems of the Museums and Libraries.
In all these cases the photographic representation of an object,
evidently, is one of the basic components of the divers object
descriptions levels, in an Information System (Lagerqvist B,
1999). Likewise, the importance and the possibilities of the pho-
togrammetry, on the process of object description, are recog-
nized as well. For this reason, in the research area is emphasized
the necessity for continuous development and integration of
close-range vision techniques and spatial information systems
for recording, 3D reconstruction, modeling and visualization of
structures of Cultural Heritage (Patias. P., 2001)
Thus, a great portion of the research is driven towards:
e the production of an appropriate model, this means a geo-
metrically accurate and detailed photo model,
e the navigation and VR representation, as well as the use of
Internet, to facilitate promotion of Cultural Heritage.
Starting from this point, a large number of inter-connected prob-
lems need the optimum solutions. The problem of LoD (Level
of details) generation is a central one and is referred to both
geometric and texture (raster) data. The parameters, that com-
pose and define the general problem of LoD are many (Patias,
P., Tsioukas, V., Sechidis, L., 2001). One of them concerns the
image format. What image format is the most appropriate to
manipulate efficiently the huge data sets in and out of the
world-wide-web? The most common formats like TIFF, GIF or
JPEG used today, have advantages and give us good results
concerning the image quality. A major point however, is a pre-
defined resolution. A way, to overcome the majority of the
above mentioned problems, seems to be the use, of an almost
new format, like FlashPix (FPX) format. FlashPix is a graphics
file format developed by Microsoft, Live Picture, Hewlett-
Packard, and Eastman Kodak, while Netscape announced full
support. It is a resolution - independent format, that can handle
efficiently any kind of images at any resolution, offering at the
same time major advantages, among them networking as well.
2. PHILOSOPHY OF FLASHPIX FORMAT
In digital photogrammetry, one of the most common drawbacks,
we are facing with, is the manipulation of huge image data.
High resolution images are needed to be mapped on model sur-
faces (image mapping), in order to have the most of the object
details. For a medium powered computer system, this results in
large processing time. Additionally, various presentation meth-
ods and effects, like walk — through paths, add more processing
time to the already large one. These problems appear to be
common ones in all image proccessing procedures. The devel-
opment of the FlashPix format is based on the philosophy that a
common user, with a medium powered computer system, during
any image process, should be able to hadle efficiently and effec-
tivly these huge image data sets.
FlashPix format supports images of any size, and any resolu-
tion. The main idea for the FPX format is: *you see what you
ask for”. Images in FlashPix files are stored at multiple inde-
pendent resolutions. This means that the FPX format stores data
in various levels of detail, starting from raw image to highly
generalised one. Even more, in each level of detail, it stores data
into square tiles, which can be independently managed. This
structure allows applications to select the appropriate resolution
for a certain procedure and to access directly the specific areas
of an image needed for the operation being performed. This
eliminates the need to process the entire image for viewing a
small part of it, or to handle a large amount of data (high resolu-
tion image) in order to produce a smaller amount of data (dis-
playing a lower resolution image).
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