A REDUCED MULTIPLE GABOR FRAME FOR LOCAL TIME ADAPTATION OF THE SPECTROGRAM

Marco Liuni (1) , Axel Röbel (1) , Romito Marco (2) , Xavier Rodet (1)

1 IRCAM - Institut de Recherche et Coordination Acoustique/Musique
2 Dipartimento di Matematica "Ulisse Dini"

In this paper we propose a method for automatic local time adaptation of the spectrogram of an audio signal, based on its decomposition within a Gabor multi-frame. The sparsity of the analyses within each individual frame is evaluated through the Rényi entropies measures. According to the sparsity of the decompositions, an optimal resolution and a reduced multi-frame are determined, defining an adapted spectrogram with variable resolution and hop size. The composition of such a reduced multi-frame allows an immediate definition of a dual frame: re-synthesis techniques for this adapted analysis are easily derived by the traditional phase vocoder scheme.

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

Marco Liuni, Axel Röbel, Romito Marco, Xavier Rodet. A REDUCED MULTIPLE GABOR FRAME FOR LOCAL TIME ADAPTATION OF THE SPECTROGRAM. Proc. of the 13th Int. Conference on Digital Audio Effects (DAFx-10), Sep 2010, Graz, Austria. pp.P70. ⟨hal-00626839⟩