Illustrations
1.1 2D example of segmented volume visualization. 1.1(a) shows the
input segmented volume, and 1.1(b) renders a piecewise bi-linear
function over the segmented domain. Note that the bi-linear
classification produces smoother boundary but also maintains the
correct partition. 1.1(c) and 1.1(d) are the three material variants. . 3
1.2 Example of segmentation and our multi-material representation.
1.2(a) illustrates a typical segmented material over a low-resolution
map. The segmentation is performed by thresholding. 1.2(b) shows
the same material under our representation. 1.2(c) shows the same
map after further segmentation. 1.2(d) shows our representation
after the second segmentation. This example is the replicative
helicase G40P molecular structure.................... 4
1.3 Two-dimensional comparison of methods, (a) is a multi-material
voxel with no intensity information, (b) is the naive approach of
classifying by nearest neighbor, (c) Tiede et al. proposes a linear
filter for classification [27], but it leaves points unclassified, (d) We
propose a tri-linear representation that classifies all points within a
voxel, (e) and (f) are examples of our approach that demonstrate the
flexibility in representing contours.................... 5