2D to STL

From: lonepeak (lonepeak@aros.net)
Date: Tue Apr 18 2000 - 00:25:01 EEST


We commonly take 2D images and create 3D files. We work with two types of
image reconstruction methods: 1) 3D from planar grayscale sections, and 2)
3D from photographic representations.

In the first case, the image data is represented as slices of the actual
part. This grayscale image data is usually obtained from a sectioning
device such as medical scanners ( MR or CT), Industrial Xray scanners,
Digibot and other laser scanners, optical tissue slicers or even large
mechanical slicers such as the CGI machine. In any case we quickly
reconstruct the images/contours into a 3D file using Velocity2 Pro
(www.image3.com). This file can also be exported to STL files for the quick
fabrication of the part.

In the second case, the image data may be surfaced from texture map
intersections assuming the images/photographs are represent the top, end,
and front views OR the 3D file may be generated from a displacement map of a
single image over a base geometry. In the latter case, a histogram of the
color or grayscale intensities is created. From this histogram a displace
profile or map is applied to the base geometry. The base geometry may be
simple like a plane, or cube or more curve-shaped such as human head.
Unfortunately, getting an accurate model is not as straight forward as in
case 1. Simple Z-direction displace maps such as logos are usually pretty
easy, but facial, swept surface, and engineering component reconstructions
are sometimes more challenging. Depending on the quality of the image(s) and
the amount of useful data, we commonly use a combination of packages, such
as Maya, FormZ, Alias|Wavefront, Photoshop, and Rhino for these type of
reconstructions.

Regards,
Alair Emory/Javelin (www.javelin3d.com)

For more information about the rp-ml, see http://ltk.hut.fi/rp-ml/



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