ITAKURA-SAITO NONNEGATIVE MATRIX FACTORIZATION WITH GROUP SPARSITY
Acoustic Source Separation
Presented by: Augustin Lefevre, Author(s): Augustin Lefevre, Francis Bach, Ecole Normale Superieure, France; Cédric Févotte, CNRS LTCI / Télécom ParisTech, France
We propose an unsupervised inference procedure for audio source separation. Components in nonnegative matrix factorization (NMF) are grouped automatically in audio sources via a penalized maximum likelihood approach. The penalty term we introduce favors sparsity at the group level, and is motivated by the assumption that the local amplitude of the sources are independent. Our algorithm extends multiplicative updates for NMF; moreover we propose a test statistic to tune hyperparameters in our model, and illustrate its adequacy on synthetic data. Results on real audio tracks show that our sparsity prior allows to identify audio sources without no knowledge on their spectral properties.