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34 lines
2.9 KiB
HTML
34 lines
2.9 KiB
HTML
<html>
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<head><link rel="stylesheet" type="text/css" href="help.css" /></head>
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<body>
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<h1 class='module'>Multilevel B-Spline Interpolation</h1>
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<div class='author'>(c) 2006 by O.Conrad</div>
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<div class='description'>Multilevel B-spline algorithm for spatial interpolation of scattered data as proposed by Lee, Wolberg and Shin (1997). The algorithm makes use of a coarse-to-fine hierarchy of control lattices to generate a sequence of bicubic B-spline functions, whose sum approaches the desired interpolation function. Large performance gains are realized by using B-spline refinement to reduce the sum of these functions into one equivalent B-spline function. <br/>
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<br/>
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The 'Maximum Level' determines the maximum size of the final B-spline matrix and increases exponential with each level. Where level=10 requires about 1mb level=12 needs about 16mb and level=14 about 256mb(!) of additional memory. <br/>
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<br/>
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Reference:<br/>
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- Lee, S., Wolberg, G., Shin, S.Y. (1997): 'Scattered Data Interpolation with Multilevel B-Splines', IEEE Transactions On Visualisation And Computer Graphics, Vol.3, No.3<br/>
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</div>
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<h2>Parameters</h2>
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<dl class='parameters'>
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<dt>Points <div class='type'>Input Shapes</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Attribute <div class='type'>Table field</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Target Grid <div class='type'>Choice</div></dt><dd> <div class='constraints'>Available choices: user defined, grid</div></dd>
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<dt>Method <div class='type'>Choice</div></dt><dd> <div class='constraints'>Available choices: without B-spline refinement, with B-spline refinement</div></dd>
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<dt>Threshold Error <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Maximum Level <div class='type'>Integer</div></dt><dd> <div class='constraints'>Minimum: 1.0; Maximum: 14.0</div></dd>
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<dt>Update View <div class='type'>Boolean</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Left <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Right <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Bottom <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Top <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Cellsize <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Columns <div class='type'>Integer</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Rows <div class='type'>Integer</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Grid <div class='type'>Output Data Object</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Grid system <div class='type'>Grid system</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Grid <div class='type'>Output Grid</div></dt><dd> <div class='constraints'></div></dd>
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</dl>
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</body></html>
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