Graphics Reference
In-Depth Information
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Figure 5.3.
Three-dimensional segmentation of a fractured vertebra before and after a
surgical procedure to restore its height, using the SpineJack device from Vexim SA of
Toulouse, France. The bottom three rows show before (left) and after (right) images
overlaid with the contours of the 3D segmentations. The top row shows 3D renderings
of the segmentations, color-coded to indicate the change in height pre- and post-surgery.
The reference (leftmost) 3D vertebra is a pre-trauma reconstruction—a prediction of
the vertebra's shape before it was fractured. Filtering is used here to detect the edges
of the vertebra. [Image used with permission courtesy of Dr. David Noriega, Valladolid,
Spain, and Vexim SA.]
written as
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Separability means that these filters can be decomposed as one 1D filter along
x
and one 1D filter along
y
. The Sobel filter used for edge detection along
x
can
