ABSTRACT
Volume visualization is a method of extracting meaningful information from volumetric data using interactive graphics and imaging. It is concerned with volume data representation, modeling, manipulation, and rendering [20] [91] [92] [154]. Volume data are 3-D (possibly time-varying) entities that may have information inside them, might not consist of tangible surfaces and edges, or might be too voluminous to be represented geometrically. They are obtained by sampling, simulation, or modeling techniques. For example, a sequence of 2-D slices obtained from magnetic resonance imaging (MRI), computed tomography (CT), functional MRI (fMRI), or positron emission tomography (PET), is 3-D reconstructed into a volume model and visualized for diagnostic purposes or for planning of treatment or surgery. The same technology is often used with industrial CT for nondestructive inspection of composite materials or mechanical parts. Similarly, confocal microscopes produce data which are visualized to study the morphology of biological structures. In many computational fields, such as computational fluid dynamics, the results of simulations typically running on a supercomputer are often visualized as volume data for analysis
and verification. Recently, the subarea of volume graphics [96] has been expanding, and many traditional geometric computer graphics applications, such as CAD and flight simulation, have been exploiting the advantages of volume techniques.
