A method for transforming solid, three-dimensional image data into
three-dimensional surface data first smoothes the surface of the solid
image by removing extraneous voxels both attached to main surface of the
solid image as well as extraneous voxels about the main image before the
surface transformation. Once the solid image is transformed into a
surface image, the method again cleans the surface by removing any
significantly spiked structures that appear out of place when considered
with respect to the surrounding topography. The amount of data required
to render the surface image is reduced by removing surface facets that
fall within a planar threshold of the surrounding topography. The
topography is also compressed in local areas to bring the topography
toward a median level. The method may further cycle to attempt to reduce
additional surface facets that may fall now within the threshold limit.