Gaede, Fjedor: Efficient variational gaph methods in imaging and 3D data. 2020
Inhalt
- Contents
- 1 Introduction
- 2 Mathematical Preliminaries
- I Graph Cut-Pursuit
- 3 Introduction to Graph Processing
- 3.1 Finite Weighted Graphs
- 3.1.1 Basic Graph Terminology
- 3.1.2 Vertex and Edge Functions
- 3.1.3 First-Order Partial Difference Operators on Graphs
- 3.1.4 Total Variation Regularization on Graphs
- 3.2 Graph p-q-Laplace Operator
- 3.3 Optimization Problems on Graphs
- 3.4 Graph Cuts for Energy Minimization
- Appendix
- 3.A Reformulating p-q-Laplace Operator
- 3.B Derivative of the p-q-TV Regularizer
- 3.C Proximity Operator of the p-q-TV Regularizer
- 4 Cut-Pursuit
- 4.1 Introduction to Partitioning and Reduced Problems
- 4.2 Finer Partitioning via Graph Cuts
- 4.2.1 Refining the Partition
- 4.2.2 Solving the Partition Problem
- 4.2.3 Direction for Isotropic Cut-Pursuit
- 4.3 Cut-Pursuit Algorithm
- 4.4 Cut-Pursuit Algorithm for ROF Problems
- Appendix
- 5 Cut-Pursuit for Minimal Partition Problems
- Appendix
- 6 Numerics: Cut-Pursuit for TV Problems
- 6.1 Iterative Behavior of the Cut-Pursuit Algorithm
- 6.2 Cut-Pursuit Convergence and Runtime
- 6.3 Isotropic Cut-Pursuit and Choosing Directions
- 6.4 Debiasing
- 7 Numerics: Minimal Partition Problem
- 7.1 Comparing Different Constant Step Sizes
- 7.2 Different Partition Optimization Strategies
- 7.3 Comparison to Other Algorithms
- 7.4 Discretization via Minimal Partitions
- 8 Numerics: Point Cloud Sparsification via Cut-Pursuit
- II Dynamic PET Image Reconstruction
- 9 Introduction to PET Reconstruction
- 10 Total Variation Regularization on Reconstruction
- 11 Dynamic PET Reconstruction
- 11.1 Listmode PET Data and EM Reconstruction
- 11.2 Fully4D Reconstruction
- 11.2.1 Update for the Spatial Weights
- 11.2.2 Update for the Basis Functions
- 11.2.3 Fully4D Algorithm and Implementation Details
- 11.3 Regularized Fully4D
- 12 Numerics: Dynamic PET Reconstruction
- III Cut-Pursuit Based Reconstruction
- 13 Cut-Pursuit on PET Reconstruction
- 13.1 Graph Setting for Reconstructions
- 13.2 Cut-Pursuit for Regularized PET Reconstruction
- 13.3 Efficient Reduced Operator Computation
- 13.4 Solving the Reduced Problem
- 14 Numerics
- 14.1 Implementation Details
- 14.2 Solving the Reduced Problem
- 14.3 Full Operator Evaluations
- 14.4 Numerical Comparison
- 14.5 Comparison of Cut-Pursuit with Direct Algorithms
- 15 Summary and Conclusion
- 15.1 Efficient Cut-Pursuit Algorithm
- 15.2 Dynamic PET and Regularized Fully4D
- 15.3 Cut-Pursuit Based Reconstruction
- List of Figures
- Bibliography
- Leere Seite
