Abstract
We discuss three different affine invariant evolution processes for smoothing planar curves. The first one is derived from ageometric heat-type flow, both the initial and the smoothed curves being differentiable. The second smoothing process is obtained from a discretization of this affine heat equation. In this case, the curves are represented by planarpolygons. The third process is based onB-spline approximations. For this process, the initial curve is a planar polygon, and the smoothed curves are differentiable and even analytic. We show that, in the limit, all three affine invariant smoothing processes collapse any initial curve into anelliptic point.
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Sapiro, G., Bruckstein, A.M. The ubiquitous ellipse. Acta Appl Math 38, 149–161 (1995). https://doi.org/10.1007/BF00992844
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DOI: https://doi.org/10.1007/BF00992844