Audio source separation using a redundant library of source spectral bases for non-negative tensor factorization

This work proposes a solution to the problem of under-determined audio source separation using pre-trained redundant source-based prior information. In local Gaussian modeling of a mixing process, an observed mixture is modeled by a Gaussian distribution parameterized by source variances and spatial covariance matrices. The separation is performed by estimating the parameters, and applying Wiener filtering on the observed mixture. We propose, in a training phase, to build a redundant library of spectral basis matrices of all probable source power spectra, applying non-negative tensor factorization (NTF). In the testing phase, the matrices that match the observed mixture are detected using NTF. With the help of the detected matrices, a maximum likelihood algorithm is proposed in order to iteratively estimate the parameters of the model, exploiting the spatial redundancy of the observed mixture and using NTF. The proposed algorithm proves more flexibility and efficiency with respect to a baseline algorithm used as a reference.