Blender  V3.3
resection.h
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1 // Copyright (c) 2009 libmv authors.
2 //
3 // Permission is hereby granted, free of charge, to any person obtaining a copy
4 // of this software and associated documentation files (the "Software"), to
5 // deal in the Software without restriction, including without limitation the
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7 // sell copies of the Software, and to permit persons to whom the Software is
8 // furnished to do so, subject to the following conditions:
9 //
10 // The above copyright notice and this permission notice shall be included in
11 // all copies or substantial portions of the Software.
12 //
13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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17 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
18 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
19 // IN THE SOFTWARE.
20 //
21 // Compute the projection matrix from a set of 3D points X and their
22 // projections x = PX in 2D. This is useful if a point cloud is reconstructed.
23 //
24 // Algorithm is the standard DLT as described in Hartley & Zisserman, page 179.
25 
26 #ifndef LIBMV_MULTIVIEW_RESECTION_H
27 #define LIBMV_MULTIVIEW_RESECTION_H
28 
29 #include "libmv/logging/logging.h"
30 #include "libmv/numeric/numeric.h"
31 
32 namespace libmv {
33 namespace resection {
34 
35 // x's are 2D image coordinates, (x,y,1), and X's are homogeneous four vectors.
36 template <typename T>
37 void Resection(const Matrix<T, 2, Dynamic>& x,
38  const Matrix<T, 4, Dynamic>& X,
39  Matrix<T, 3, 4>* P) {
40  int N = x.cols();
41  assert(X.cols() == N);
42 
43  Matrix<T, Dynamic, 12> design(2 * N, 12);
44  design.setZero();
45  for (int i = 0; i < N; i++) {
46  T xi = x(0, i);
47  T yi = x(1, i);
48  // See equation (7.2) on page 179 of H&Z.
49  design.template block<1, 4>(2 * i, 4) = -X.col(i).transpose();
50  design.template block<1, 4>(2 * i, 8) = yi * X.col(i).transpose();
51  design.template block<1, 4>(2 * i + 1, 0) = X.col(i).transpose();
52  design.template block<1, 4>(2 * i + 1, 8) = -xi * X.col(i).transpose();
53  }
54  Matrix<T, 12, 1> p;
55  Nullspace(&design, &p);
56  reshape(p, 3, 4, P);
57 }
58 
59 } // namespace resection
60 } // namespace libmv
61 
62 #endif // LIBMV_MULTIVIEW_RESECTION_H
#define X
Definition: GeomUtils.cpp:199
static float P(float k)
Definition: math_interp.c:25
#define N
#define T
void Resection(const Matrix< T, 2, Dynamic > &x, const Matrix< T, 4, Dynamic > &X, Matrix< T, 3, 4 > *P)
Definition: resection.h:37
double Nullspace(TMat *A, TVec *nullspace)
Definition: numeric.h:158
void reshape(const TMat &a, int rows, int cols, TDest *b)
Definition: numeric.h:441