---
_id: '18398'
abstract:
- lang: eng
  text: We pose the problem of tissue classification in MRI as a blind source separation
    (BSS) problem and solve it by means of sparse component analysis (SCA). Assuming
    that most MR images can be sparsely represented, we consider their optimal sparse
    representation. Sparse components define a physically-meaningful feature space
    for classification. We demonstrate our approach on simulated and real multi-contrast
    MRI data. The proposed framework is general in that it is applicable to other
    modalities of medical imaging as well, whenever the linear mixing model is applicable.
article_processing_charge: No
author:
- first_name: Alexander
  full_name: Bronstein, Alexander
  id: 58f3726e-7cba-11ef-ad8b-e6e8cb3904e6
  last_name: Bronstein
  orcid: 0000-0001-9699-8730
- first_name: M.M.
  full_name: Bronstein, M.M.
  last_name: Bronstein
- first_name: M.
  full_name: Zibulevsky, M.
  last_name: Zibulevsky
- first_name: Y.Y.
  full_name: Zeevi, Y.Y.
  last_name: Zeevi
citation:
  ama: 'Bronstein AM, Bronstein MM, Zibulevsky M, Zeevi YY. “Unmixing” tissues: Sparse
    component analysis in multi-contrast MRI. In: <i>IEEE International Conference
    on Image Processing</i>. Vol 2. IEEE; 2005:1279-1282. doi:<a href="https://doi.org/10.1109/icip.2005.1530297">10.1109/icip.2005.1530297</a>'
  apa: 'Bronstein, A. M., Bronstein, M. M., Zibulevsky, M., &#38; Zeevi, Y. Y. (2005).
    “Unmixing” tissues: Sparse component analysis in multi-contrast MRI. In <i>IEEE
    International Conference on Image Processing</i> (Vol. 2, pp. 1279–1282). Genova,
    Italy: IEEE. <a href="https://doi.org/10.1109/icip.2005.1530297">https://doi.org/10.1109/icip.2005.1530297</a>'
  chicago: 'Bronstein, Alex M., M.M. Bronstein, M. Zibulevsky, and Y.Y. Zeevi. “‘Unmixing’
    Tissues: Sparse Component Analysis in Multi-Contrast MRI.” In <i>IEEE International
    Conference on Image Processing</i>, 2:1279–82. IEEE, 2005. <a href="https://doi.org/10.1109/icip.2005.1530297">https://doi.org/10.1109/icip.2005.1530297</a>.'
  ieee: 'A. M. Bronstein, M. M. Bronstein, M. Zibulevsky, and Y. Y. Zeevi, “‘Unmixing’
    tissues: Sparse component analysis in multi-contrast MRI,” in <i>IEEE International
    Conference on Image Processing</i>, Genova, Italy, 2005, vol. 2, pp. 1279–1282.'
  ista: 'Bronstein AM, Bronstein MM, Zibulevsky M, Zeevi YY. 2005. ‘Unmixing’ tissues:
    Sparse component analysis in multi-contrast MRI. IEEE International Conference
    on Image Processing. ICIP: International Conference on Image Processing vol. 2,
    1279–1282.'
  mla: 'Bronstein, Alex M., et al. “‘Unmixing’ Tissues: Sparse Component Analysis
    in Multi-Contrast MRI.” <i>IEEE International Conference on Image Processing</i>,
    vol. 2, IEEE, 2005, pp. 1279–82, doi:<a href="https://doi.org/10.1109/icip.2005.1530297">10.1109/icip.2005.1530297</a>.'
  short: A.M. Bronstein, M.M. Bronstein, M. Zibulevsky, Y.Y. Zeevi, in:, IEEE International
    Conference on Image Processing, IEEE, 2005, pp. 1279–1282.
conference:
  end_date: 2005-09-14
  location: Genova, Italy
  name: 'ICIP: International Conference on Image Processing'
  start_date: 2005-09-11
date_created: 2024-10-15T11:20:54Z
date_published: 2005-09-15T00:00:00Z
date_updated: 2024-11-12T08:22:13Z
day: '15'
doi: 10.1109/icip.2005.1530297
extern: '1'
fulldoi: https://doi.org/10.1109/icip.2005.1530297
intvolume: '         2'
language:
- iso: eng
month: '09'
oa_version: None
page: 1279-1282
publication: IEEE International Conference on Image Processing
publication_identifier:
  isbn:
  - '0780391349'
publication_status: published
publisher: IEEE
quality_controlled: '1'
scopus_import: '1'
status: public
title: '"Unmixing" tissues: Sparse component analysis in multi-contrast MRI'
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 2
year: '2005'
...
---
_id: '18399'
abstract:
- lang: eng
  text: Recently, it was proven empirically that facial expressions can be modelled
    as isometries, that is, geodesic distances on the facial surface were shown to
    be significantly less sensitive to facial expressions compared to Euclidean ones.
    Based on this assumption, the 3DFACE face recognition system was built. The system
    efficiently computes expression invariant signatures based on isometry-invariant
    representation of the facial surface. One of the crucial steps in the recognition
    system was embedding of the face geometric structure into a Euclidean (flat) space.
    Here, we propose to replace the flat embedding by a spherical one to construct
    isometric invariant representations of the facial image. We refer to these new
    invariants as spherical canonical images. Compared to its Euclidean counterpart,
    spherical embedding leads to notably smaller metric distortion. We demonstrate
    experimentally that representations with lower embedding error lead to better
    recognition. In order to efficiently compute the invariants we introduce a dissimilarity
    measure between the spherical canonical images based on the spherical harmonic
    transform.
article_processing_charge: No
author:
- first_name: Alexander
  full_name: Bronstein, Alexander
  id: 58f3726e-7cba-11ef-ad8b-e6e8cb3904e6
  last_name: Bronstein
  orcid: 0000-0001-9699-8730
- first_name: M.M.
  full_name: Bronstein, M.M.
  last_name: Bronstein
- first_name: R.
  full_name: Kimmel, R.
  last_name: Kimmel
citation:
  ama: 'Bronstein AM, Bronstein MM, Kimmel R. Expression-invariant face recognition
    via spherical embedding. In: <i>International Conference on Image Processing</i>.
    Vol 3. IEEE; 2005:756-759. doi:<a href="https://doi.org/10.1109/icip.2005.1530502">10.1109/icip.2005.1530502</a>'
  apa: 'Bronstein, A. M., Bronstein, M. M., &#38; Kimmel, R. (2005). Expression-invariant
    face recognition via spherical embedding. In <i>International Conference on Image
    Processing</i> (Vol. 3, pp. 756–759). Genova, Italy: IEEE. <a href="https://doi.org/10.1109/icip.2005.1530502">https://doi.org/10.1109/icip.2005.1530502</a>'
  chicago: Bronstein, Alex M., M.M. Bronstein, and R. Kimmel. “Expression-Invariant
    Face Recognition via Spherical Embedding.” In <i>International Conference on Image
    Processing</i>, 3:756–59. IEEE, 2005. <a href="https://doi.org/10.1109/icip.2005.1530502">https://doi.org/10.1109/icip.2005.1530502</a>.
  ieee: A. M. Bronstein, M. M. Bronstein, and R. Kimmel, “Expression-invariant face
    recognition via spherical embedding,” in <i>International Conference on Image
    Processing</i>, Genova, Italy, 2005, vol. 3, pp. 756–759.
  ista: 'Bronstein AM, Bronstein MM, Kimmel R. 2005. Expression-invariant face recognition
    via spherical embedding. International Conference on Image Processing. ICIP: International
    Conference on Image Processing vol. 3, 756–759.'
  mla: Bronstein, Alex M., et al. “Expression-Invariant Face Recognition via Spherical
    Embedding.” <i>International Conference on Image Processing</i>, vol. 3, IEEE,
    2005, pp. 756–59, doi:<a href="https://doi.org/10.1109/icip.2005.1530502">10.1109/icip.2005.1530502</a>.
  short: A.M. Bronstein, M.M. Bronstein, R. Kimmel, in:, International Conference
    on Image Processing, IEEE, 2005, pp. 756–759.
conference:
  end_date: 2005-09-14
  location: Genova, Italy
  name: 'ICIP: International Conference on Image Processing'
  start_date: 2005-09-14
date_created: 2024-10-15T11:20:54Z
date_published: 2005-09-15T00:00:00Z
date_updated: 2024-11-12T08:18:51Z
day: '15'
doi: 10.1109/icip.2005.1530502
extern: '1'
fulldoi: https://doi.org/10.1109/icip.2005.1530502
intvolume: '         3'
language:
- iso: eng
month: '09'
oa_version: None
page: 756-759
publication: International Conference on Image Processing
publication_identifier:
  isbn:
  - '0780391349'
publication_status: published
publisher: IEEE
quality_controlled: '1'
scopus_import: '1'
status: public
title: Expression-invariant face recognition via spherical embedding
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 3
year: '2005'
...