Sk. Semwal et Bk. Barnhart, RAY CASTING AND THE ENCLOSING-NET ALGORITHM FOR EXTRACTING SHAPES FROM VOLUME DATA, Computers in biology and medicine, 25(2), 1995, pp. 261-276
One of the most useful applications of virtual reality is to let docto
rs view the inside of the human body non-invasively and in real time.
In this paper, we first survey the area of virtual reality and volume-
visualization techniques. We discuss our ray casting implementation fo
r viewing the medical data which is available as a set of slices from
NMR and CT scans. Next we present a new method, the enclosing-net algo
rithm, for extracting iso-surfaces from volume data. A simple implemen
tation of our technique is described. Since the topology of the extrac
ted surface is well defined and non-ambiguous, the enclosing-net algor
ithm eliminates a major problem of surface extraction techniques. In a
ddition, the number of polygons representing the surface can be contro
lled to obtain a finer shape. Therefore real-time interaction is feasi
ble on both low-end and high-end graphics machines, making the enclosi
ng-net algorithm suitable for virtual reality experiments.