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Virtual Reality is a new era for computer Multimedia research in
the recent year. Significantly, Virtual Reality is not a new
revolution of computer technique, it is an integration of
existing technologies such as computer graphics, image
procession, sound effect, and real-time control to form a new
type of human-computer interface. The goal of Virtual Reality
technique is to let the user to fully immerse into the
computerized synthetic world which is complete new experience
for Multimedia study.The key concept of virtual environment is
not only to realistically render the synthetic scene but also to
interact with user input as soon as possible. For example,
user's action of moving an object inside a virtual scene, this
object's position must be realistic update with user's synthetic
hand. For a realistic simulation, this object movement must be
presented as a series of images with the frame rate of 20 to 30
per second for human eye's perception. This high demand of
display frequency bring up thThe number of moving objects inside
the virtual scene is one of the key factor that influence the
performance of a VR database. Besides, the speed of data search
and update will also significantly impact the efficiency of a VR
database. Hence, a new approach to design an efficient VR
database for faster data search and update capabilities is
presented in this thesis.Since VRML 2.0 is an industrial
standard language to describe a virtual scene over WWW, the
approach of this thesis start from parsing a virtual scene,
which is described by VRML 2.0, into a set of 128*128*128
octants of "full octree". By this way, objects inside the
virtual scene is then implicitly localized, which will then
efficiently reduce the number of collision detection
computation. Also, the computation required to search for
objects inside viewer's field-of-view and calculate of objects'
level-o
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