A NEW ALGORITHM FOR GENERATING QUADRILATERAL MESHES AND ITS APPLICATION TO FE-BASED IMAGE REGISTRATION S. Ramaswami
M. Siqueira
T. Sundaram
J. Gallier
J. Gee
½ Rutgers University, Camden, NJ 08102, USA,
[email protected] ¾ University of Pennsylvania, Philadelphia, PA 19104, USA, marcelos,tessa@seas.upenn.edu ¿ Universidade Federal de Mato Grosso do Sul, Campo Grande, MS 79070-900, Brazil.
ABSTRACT
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1.
INTRODUCTION
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(1 2* 3 $
().* ? $ 3. THE ALGORITHM
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D $ $ 9- 9+ 8 3.1 Polygonal Regions with Holes
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Figure 1: The non-empty triangle H.
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Figure 2: (a) Degenerate quadrilateral. (b) Degenerate pentagon.
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Figure 6: Cases i and ii of Step 4c.
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Figure 5: Cases 4a and 4b of Step 4.
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Figure 7: Case iii of Step 4c (dashed edges are cross-edges).
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Figure 8: for case iv of Step 4c (dashed edges are cross-edges).
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3.3 Constrained Quadrilateral Meshes
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MESHES FROM IMAGES
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Figure 10: Contours of a human brain image.
Figure 9: (a) Triangular mesh of “Lake Superior”. (b) Quadrilateral mesh of Lake Superior. (c) Mesh in (a) after post-processing.
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5. AN APPLICATION (+6*
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: )K. +6 +/ -6 -- : /K2 $ )K. : 5K)+ /K2 : )-K)0 2 2 . . + + ) )
Figure 11: (a) Source image. (b) Target image and its associated mesh. (c) Image resulting from warping image in (a). (d) Subtraction of (c) from image in (b).
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.-5+ /--2 1-5. )+.+0 --6) -251 /)2/ 202) -//1 .)0) //)1 56.+))+ 2-+6 --6+. )-)/2.
Table 1: Size of the meshes 1–16.
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Table 2: Summary of the registration results.
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' D8 L D JJ;6+6.+5- JDI$ ?! References
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5 +/1K+10 )552 (0* ? 3 ; 8 8 R B F8 J C I 8 G * & 3 &&3 =DJ8 +++- 0+-K0-/ 8 B +66)
(1* 8 N = @3 " FC : J I# 8$ JG * 1 45 0)K 10 )552 (2* B D 8 N " FC : J J I# ; JG
* 5 45 +)1K++/ +666 (5* : L % FJ 8 Q : : C G * 0 45 .-1K..1 )551 ()6* 3 Q N F L = -
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