Voxels, volume rendering and volume graphics
Volume rendering, or more generally spoken volume graphics, is a
sub-specialty of 3D computer graphics which is concerned with the
discrete representation and visualization of objects represented
as sampled data in three or more dimensions. A volume/voxel data
set is a three-dimensional array of voxels. The term voxel
is used to characterize a volume element; it is a generalization
of the notion of pixel that stands for a picture element.
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| Medical CT/NMR scanners are a typical
and widely known source of voxel data. |
Volume graphics or volume rendering has inherent advantages
for applications needing visualization of irregular objects, or
where the interior structure is important, or where high level
of details and realism is essential - e.g., representations of
the human body. Volume graphics is also the choice for CGI
manufacturers needing true physics based models of real world
phenomena.
While todays widely used 3D computer graphics uses polygonal
meshes to represent an object by its surface, only volume
graphics uses voxels - 3D or volumetric pixels - as basic
element to represent not only the surface but also the entire
inner of an object.
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| A volume data set is
built up from voxels on a regular 3D grid. |
Volume graphics visualization today is superior to polygon
based 3D graphics in means of image quality and performance when
highly complex objects with finest details have to be
visualized.
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