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From previous lectures …. Orthogonal group. What is the set of transformations that preserve the inner product? Remember inner product under a transformation? More on this later …. Gram-Schmidt orthogonalization. MEMENTO! will appear in calibration (aka Q-R) Structure of the
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From previous lectures … An Introduction to 3-D Vision
Orthogonal group • What is the set of transformations that preserve the inner product? • Remember inner product under a transformation? • More on this later … An Introduction to 3-D Vision
Gram-Schmidt orthogonalization MEMENTO! will appear in calibration (aka Q-R) Structure of the Parameter matrix An Introduction to 3-D Vision
Structure induced by a linear map A X X’ Ra(A) T T Ra(A ) Nu(A) T T Nu(A ) Ra(A) Nu(A) An Introduction to 3-D Vision
Eigenvalues and eigenvectors • Eigenvalues and eigenvectors encode the “essence” of the linear map represented by A: the range space, the null space, the rank, the norm etc. • How do the notions of eigenvalues and eigenvectors generalize to NON-SQUARE matrices? • SVD, later … An Introduction to 3-D Vision
Symmetric matrices An Introduction to 3-D Vision
Symmetric matrices (contd.) An Introduction to 3-D Vision
Lecture 2: some useful tools from linear algebra The Singular Value Decomposition Least-squares solution of linear systems Basic concepts from optimization Lagrange multipliers An Introduction to 3-D Vision
The singular value decomposition An Introduction to 3-D Vision
The SVD (contd.) An Introduction to 3-D Vision
The SVD: geometric interpretation A An Introduction to 3-D Vision
Pseudo-inverse and linear systems An Introduction to 3-D Vision
Fixed-rank approximation • Useful for matrix factorization • MEMENTO! An Introduction to 3-D Vision
Preview of coming attractions • Characterization of the essential matrix • Least-squares solution of Ax=b • Computation of null-space • In general, orthogonal projections An Introduction to 3-D Vision
Unconstrained optimization An Introduction to 3-D Vision
Unconstrained optimization (contd.) An Introduction to 3-D Vision
Iterative minimization (local) • Steepest descent: • Newton’s method: • More in general: An Introduction to 3-D Vision
Gauss-Newton, Levemberg-Marquardt • Quadratic cost function • No second derivatives An Introduction to 3-D Vision
Constrained optimization An Introduction to 3-D Vision
Lagrangian function and multipliers An Introduction to 3-D Vision
Preview of coming attractions • Optimal triangulation An Introduction to 3-D Vision