LTS2

LTS2 is a team of researchers led by Prof. Pierre Vandergheynst working at the Institute of Electrical Engineering of the Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland. LTS2 is one of the EPFL Signal Processing Laboratories.

Our research focuses on complex data processing.

Data nowadays come in overwhelming volume. In order to cope with this deluge, we explore and use the benefits of geometry and symmetry in higher dimensional data. But volume is not the only problem: data models are also increasingly complex, mixing various components. We thus use redundant dictionaries as a dimensionality reduction tool to dig out information from complicated high-dimensional datasets and multichannel signals, or to model complex behaviours in more classical signals. Finally data can also be complex because they are collected on surfaces, or more generally manifolds, or because they are not scalar-valued. We thus explore extensions of Computational Harmonic Analysis in higher dimensions, in complex geometries or for non-scalar data.

Some of our application fields:

• Visual Information Processing: flexible data compression, segmentation ...
• Multichannel, Multimodal or Multi-stream data processing
• Omnidirectional light fields and other signals on manifolds
• Applications in Physics, biomedical data processing ...

See our research projects page for more details.

News:

• [August 2010] We have 4 papers accepted at ICIP'10. See you next September!
  • "Towards unifying diffusion and exemplar-based inpainting" by E. d'Angelo and P. Vandergheynst (pdf) ;
  • "Hyper-DEMIX: Blind Source Separation of Hyperspectral Images Using Local ML Estimates" by S. Arberet (pdf) ;
  • "Plenoptic based super-resolution for omnidirectional image sequences" by L. Bagnato, Y. Boursier, P. Frossard and P. Vandergheynst (pdf) ;
  • "Stream Carving: an Adaptive Seam Carving Algorithm" by D. Domingues, A. Alahi and P. Vandergheynst (infoscience).
• [May 2010] We have just released the Spectral Graph Wavelet Toolbox ! Download it here.
• [May 2010] We are updating our project proposal page. Don't forget to give it a look if you're looking for a semester / diploma project!
• [December 2009] New paper on Spread spectrum for accelerated acquisition in magnetic resonance imaging submitted to IEEE Transactions on Image Processing.
• [November 2009] New paper on Omnidirectional Structure from Motion submitted to IEEE Transactions on Image Processing.
• [November 2009] New paper on Spectral Graph Wavelets submitted to Applied and Computational Harmonic Analysis.
• [October 2009] New paper accepted in Applied and Computational Harmonic Analysis.
• [September 2009] Alexandre Alahi has won the 2009 ICDSC Challenge. The challenge, held yearly during the joint IEEE-ACM conference on Smart and Distributed Camera Systems, aims at benchmarking algorithms on a common data set. This edition focused on algorithms to detect and track pedestrians in camera networks.
• [August 2009] New paper accepted in IEEE Transactions on Neural Networks
• [July 2009] Paper "Spread spectrum for imaging techniques in radio interferometry" by Y. Wiaux et al. submitted to Monthly Notices of the Royal Astronomical Society. More on Y. Wiaux's homepage.
• [July 2009] Paper "Compressed sensing for radio interferometry: spread spectrum imaging techniques" by Y. Wiaux et al. invited at SPIE 2009 Conference WAVELET XIII. More on Y. Wiaux's homepage.
• [July 8, 2009] Official release of the Basis Pursuit De Quantization (BPDQ) toolbox by D. Hammond, L. Jacques and M.J. Fadili.
• [June 30, 2009] Three papers accepted to ICIP'09:
  • "Optical Flow and Depth from Motion for Omnidirectional Images Using a TV-L1 Variational Framework on Graphs" by L. Bagnato, P. Frossard, and P. Vandergheynst;
  • "TV-Regularized Generation of Planar Images from Omnicams" by Y. Boursier, L. Jacques, D. Raboud, P. Frossard, M.J. Fadili, P. Vandergheynst (pdf);
  • "Dequantizing Compressed Sensing with Non-Gaussian Constraints" by L. Jacques, D. K. Hammond, and M. J. Fadili (pdf);
• [April 2009] Paper "Wavelet domain Bayesian denoising of string signal in the cosmic microwave background" by D. K. Hammond, Y. Wiaux and P. Vandergheynst accepted for publication in Monthly Notices of the Royal Astronomical Society
• [April 2009] New paper submitted to Appl. Comp. Harmonic Analysis.
• [April 2009] Paper "A Sparsity Constrained Inverse Problem to Locate People in a Network of Cameras" by A. Alahi, Y. Boursier, L. Jacques, P. Vandergheynst accepted to DSP 2009.
• [March 2009] Geometric video approximations with matching pursuit accepted at IEEE TIP.
• [February 2009] Classification via incoherent subspaces submitted to PAMI.
• [February 2009] Paper "Compressed sensing imaging techniques for radio interferometry" by Y. Wiaux et al. accepted for publication in Monthly Notices of the Royal Astronomical Society
• [February 2009] 2 papers submitted to the ICIP'09 conference and one to the DSP'09 conference (more...)
• [January 2009] We have open PhD and Post Doc positions. See our job offers !
• ... all the news.