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From: Walter Roberson <roberson@hushmail.com>
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Subject: Re: 3D CT reconstruction
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Date: Tue, 02 Dec 2008 09:24:31 -0600
Xref: news.mathworks.com comp.soft-sys.matlab:504396


maya wrote:
> I am trying to reconstruct 3D image from 2D CT slices using delaunay triangulation. Can anybody
> say how to use the delaunay function in Matlab for the above

Based upon the information you supplied in your previous round of postings,
it is not possible to use Delaunay triangulation to do the reconstruction
that you hoped to do.

Delaunay triangulation is for the case where you have points in space, and
you have places where the points are not. That does not match the situation you
described before, where you have a complete matrix of voxels, each of which is
a volume of a different intensity, and you wish to connect together certain
voxels that (if I recall correctly) you have no present algorithm for
firmly differentiating from other voxels. Your segmentation work needs to
start with the aspect of differentiating the voxels of interest from those
that are not of interest: only then should you be concerned about reconstruction.


-- 
.signature note: I am now avoiding replying to unclear or ambiguous postings.
Please review questions before posting them. Be specific. Use examples of what you mean,
of what you don't mean. Specify boundary conditions, and data classes and value
relationships -- what if we scrambled your data or used -Inf, NaN, or complex(rand,rand)?