Model-based Matching Pursuit - Estimation of Chirp Factors and Scale of Gabor Atoms with Iterative Extension

Pierre Leveau (1) , Laurent Daudet (1) , Sacha Krstulovic (2) , Rémi Gribonval (2)

1 LAM - Laboratoire d'acoustique musicale
2 METISS - Speech and sound data modeling and processing

By definition, the Matching Pursuit algorithm with constant (or "flat") Gabor atoms provides a coarse estimate of frequency modulated sinusoids in music and voice signals. Chirped Gabor atoms, closer to the nature of these signals, would fit them in a finer and sparser way. Though a method for the direct analytic estimation of chirped Gabor atoms has been proposed in the past, the present article proposes an alternative method where the chirp factor and scale parameter are estimated through a regression over an iteratively selected chain of small-scale atoms defined by a Short Time Fourier Transform. This new technique suits the Matching Pursuit framework, and is compared with a "flat atoms" version of the algorithm. The influence of various frequency interpolation techniques over the sparsity of the resulting representation is also studied.

Domaines: Traitement du signal et de l'image [eess.SP]; Traitement du signal et de l'image [eess.SP]

Pierre Leveau, Laurent Daudet, Sacha Krstulovic, Rémi Gribonval. Model-based Matching Pursuit - Estimation of Chirp Factors and Scale of Gabor Atoms with Iterative Extension. Signal Processing with Adaptive Sparse Structured Representations (SPARS'05), IRISA, Nov 2005, Rennes, France. ⟨inria-00583654⟩