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Accurate Optimization of Weighted Nuclear Norm for Non-Rigid Structure from Motion

Iglesias, José Pedro ; Olsson, Carl LU and Valtonen Örnhag, Marcus LU (2020) 16th European Conference on Computer Vision, ECCV 2020 In Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 12372 LNCS. p.21-37
Abstract

Fitting a matrix of a given rank to data in a least squares sense can be done very effectively using 2nd order methods such as Levenberg-Marquardt by explicitly optimizing over a bilinear parameterization of the matrix. In contrast, when applying more general singular value penalties, such as weighted nuclear norm priors, direct optimization over the elements of the matrix is typically used. Due to non-differentiability of the resulting objective function, first order sub-gradient or splitting methods are predominantly used. While these offer rapid iterations it is well known that they become inefficient near the minimum due to zig-zagging and in practice one is therefore often forced to settle for an approximate solution. In this paper... (More)

Fitting a matrix of a given rank to data in a least squares sense can be done very effectively using 2nd order methods such as Levenberg-Marquardt by explicitly optimizing over a bilinear parameterization of the matrix. In contrast, when applying more general singular value penalties, such as weighted nuclear norm priors, direct optimization over the elements of the matrix is typically used. Due to non-differentiability of the resulting objective function, first order sub-gradient or splitting methods are predominantly used. While these offer rapid iterations it is well known that they become inefficient near the minimum due to zig-zagging and in practice one is therefore often forced to settle for an approximate solution. In this paper we show that more accurate results can in many cases be achieved with 2nd order methods. Our main result shows how to construct bilinear formulations, for a general class of regularizers including weighted nuclear norm penalties, that are provably equivalent to the original problems. With these formulations the regularizing function becomes twice differentiable and 2nd order methods can be applied. We show experimentally, on a number of structure from motion problems, that our approach outperforms state-of-the-art methods.

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Please use this url to cite or link to this publication:
author
; and
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
host publication
Computer Vision – ECCV 2020 - 16th European Conference, 2020, Proceedings
series title
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
editor
Vedaldi, Andrea ; Bischof, Horst ; Brox, Thomas and Frahm, Jan-Michael
volume
12372 LNCS
pages
17 pages
publisher
Springer Science and Business Media B.V.
conference name
16th European Conference on Computer Vision, ECCV 2020
conference location
Glasgow, United Kingdom
conference dates
2020-08-23 - 2020-08-28
external identifiers
  • scopus:85097399749
ISSN
0302-9743
1611-3349
ISBN
9783030585822
DOI
10.1007/978-3-030-58583-9_2
language
English
LU publication?
yes
id
bf2e3e7c-8c39-42db-b206-14105f3f038e
date added to LUP
2020-12-22 12:22:34
date last changed
2024-04-03 20:02:02
@inproceedings{bf2e3e7c-8c39-42db-b206-14105f3f038e,
  abstract     = {{<p>Fitting a matrix of a given rank to data in a least squares sense can be done very effectively using 2nd order methods such as Levenberg-Marquardt by explicitly optimizing over a bilinear parameterization of the matrix. In contrast, when applying more general singular value penalties, such as weighted nuclear norm priors, direct optimization over the elements of the matrix is typically used. Due to non-differentiability of the resulting objective function, first order sub-gradient or splitting methods are predominantly used. While these offer rapid iterations it is well known that they become inefficient near the minimum due to zig-zagging and in practice one is therefore often forced to settle for an approximate solution. In this paper we show that more accurate results can in many cases be achieved with 2nd order methods. Our main result shows how to construct bilinear formulations, for a general class of regularizers including weighted nuclear norm penalties, that are provably equivalent to the original problems. With these formulations the regularizing function becomes twice differentiable and 2nd order methods can be applied. We show experimentally, on a number of structure from motion problems, that our approach outperforms state-of-the-art methods.</p>}},
  author       = {{Iglesias, José Pedro and Olsson, Carl and Valtonen Örnhag, Marcus}},
  booktitle    = {{Computer Vision – ECCV 2020 - 16th European Conference, 2020, Proceedings}},
  editor       = {{Vedaldi, Andrea and Bischof, Horst and Brox, Thomas and Frahm, Jan-Michael}},
  isbn         = {{9783030585822}},
  issn         = {{0302-9743}},
  language     = {{eng}},
  pages        = {{21--37}},
  publisher    = {{Springer Science and Business Media B.V.}},
  series       = {{Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)}},
  title        = {{Accurate Optimization of Weighted Nuclear Norm for Non-Rigid Structure from Motion}},
  url          = {{http://dx.doi.org/10.1007/978-3-030-58583-9_2}},
  doi          = {{10.1007/978-3-030-58583-9_2}},
  volume       = {{12372 LNCS}},
  year         = {{2020}},
}