1 // Ceres Solver - A fast non-linear least squares minimizer 2 // Copyright 2013 Google Inc. All rights reserved. 3 // http://code.google.com/p/ceres-solver/ 4 // 5 // Redistribution and use in source and binary forms, with or without 6 // modification, are permitted provided that the following conditions are met: 7 // 8 // * Redistributions of source code must retain the above copyright notice, 9 // this list of conditions and the following disclaimer. 10 // * Redistributions in binary form must reproduce the above copyright notice, 11 // this list of conditions and the following disclaimer in the documentation 12 // and/or other materials provided with the distribution. 13 // * Neither the name of Google Inc. nor the names of its contributors may be 14 // used to endorse or promote products derived from this software without 15 // specific prior written permission. 16 // 17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 18 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 21 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 // POSSIBILITY OF SUCH DAMAGE. 28 // 29 // Author: sameeragarwal (at) google.com (Sameer Agarwal) 30 // 31 // Detailed descriptions of these preconditions beyond what is 32 // documented here can be found in 33 // 34 // Bundle Adjustment in the Large 35 // S. Agarwal, N. Snavely, S. Seitz & R. Szeliski, ECCV 2010 36 // http://www.cs.washington.edu/homes/sagarwal/bal.pdf 37 38 #ifndef CERES_INTERNAL_SCHUR_JACOBI_PRECONDITIONER_H_ 39 #define CERES_INTERNAL_SCHUR_JACOBI_PRECONDITIONER_H_ 40 41 #include <set> 42 #include <vector> 43 #include <utility> 44 #include "ceres/collections_port.h" 45 #include "ceres/internal/macros.h" 46 #include "ceres/internal/scoped_ptr.h" 47 #include "ceres/preconditioner.h" 48 49 namespace ceres { 50 namespace internal { 51 52 class BlockRandomAccessDiagonalMatrix; 53 class BlockSparseMatrix; 54 struct CompressedRowBlockStructure; 55 class SchurEliminatorBase; 56 57 // This class implements the SCHUR_JACOBI preconditioner for Structure 58 // from Motion/Bundle Adjustment problems. Full mathematical details 59 // can be found in 60 // 61 // Bundle Adjustment in the Large 62 // S. Agarwal, N. Snavely, S. Seitz & R. Szeliski, ECCV 2010 63 // http://www.cs.washington.edu/homes/sagarwal/bal.pdf 64 // 65 // Example usage: 66 // 67 // Preconditioner::Options options; 68 // options.preconditioner_type = SCHUR_JACOBI; 69 // options.elimination_groups.push_back(num_points); 70 // options.elimination_groups.push_back(num_cameras); 71 // SchurJacobiPreconditioner preconditioner( 72 // *A.block_structure(), options); 73 // preconditioner.Update(A, NULL); 74 // preconditioner.RightMultiply(x, y); 75 // 76 class SchurJacobiPreconditioner : public BlockSparseMatrixPreconditioner { 77 public: 78 // Initialize the symbolic structure of the preconditioner. bs is 79 // the block structure of the linear system to be solved. It is used 80 // to determine the sparsity structure of the preconditioner matrix. 81 // 82 // It has the same structural requirement as other Schur complement 83 // based solvers. Please see schur_eliminator.h for more details. 84 SchurJacobiPreconditioner(const CompressedRowBlockStructure& bs, 85 const Preconditioner::Options& options); 86 virtual ~SchurJacobiPreconditioner(); 87 88 // Preconditioner interface. 89 virtual void RightMultiply(const double* x, double* y) const; 90 virtual int num_rows() const; 91 92 private: 93 void InitEliminator(const CompressedRowBlockStructure& bs); 94 virtual bool UpdateImpl(const BlockSparseMatrix& A, const double* D); 95 96 Preconditioner::Options options_; 97 98 // Sizes of the blocks in the schur complement. 99 vector<int> block_size_; 100 scoped_ptr<SchurEliminatorBase> eliminator_; 101 102 // Preconditioner matrix. 103 scoped_ptr<BlockRandomAccessDiagonalMatrix> m_; 104 CERES_DISALLOW_COPY_AND_ASSIGN(SchurJacobiPreconditioner); 105 }; 106 107 } // namespace internal 108 } // namespace ceres 109 110 #endif // CERES_INTERNAL_SCHUR_JACOBI_PRECONDITIONER_H_ 111
