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To the Graduate Council: I am submitting herewith a thesis written by ...

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Chapter 5: Analysis and Results 72SCM =0.6 SCM = 1.276 SCM =2.2(a) (b) (c)Figure 5.9: Shape information and surface ruggedness. (a) Shape informationmeasured on a DEM of a plain terrain. (c) Shape information on a plateau terrain. (d)Shape information on a mountainous terrain.In Figure 5.9 we show three surfaces. Figure 5.9(a) can be considered to represent aplain while Figure 5.9(b) and 5.9(c) represent a plateau and a mountainous region,respectively. We have color coded each of <strong>the</strong>se surfaces <strong>by</strong> <strong>the</strong> scale that we show in<strong>the</strong> picture. In agreement to our perceptual thinking we observe that <strong>the</strong> informationthat <strong>the</strong> total curvature conveys about each of <strong>the</strong>se surfaces is well quantified <strong>by</strong>SCM.5.3.3 3D Mesh ModelsWe see that <strong>the</strong> CVM algorithm behaves as expected in Figure 5.9 (a) – (c) but still notrobust because of <strong>the</strong> assumption on resolution and s<strong>am</strong>pling. We counter <strong>the</strong> problemof resolution as lack of information. We compensate with <strong>the</strong> information that for acontour its circumscribing circle of <strong>the</strong> s<strong>am</strong>e resolution, a plane of <strong>the</strong> s<strong>am</strong>e resolutionfor a surface and a circumscribing sphere for 3D models would have <strong>the</strong> least shapeinformation. We use <strong>the</strong> circumscribing reference because it is easy to determine from<strong>the</strong> characteristics of <strong>the</strong> model and we might lose an important length dimension if wemake use of an inscribed reference. The inscribed sphere, for instance, on a cylindercould turn out to be too small compared to <strong>the</strong> size of <strong>the</strong> cylinder and might not be agood reference. We measured shape complexity as <strong>the</strong> shape information distancebetween <strong>the</strong> two datasets and used <strong>the</strong> KL divergence measure (Equation 4.24) on superquadrics of varying shape factors. We present those results in Figure 5.10.

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