Blind Audio Source Separation - Conclusion

We deal with the case where the sources are linearly mixed and the mixtures are underdetermined. Hence, A has more columns than rows. Sparsity of the sources is vital for good separation. Bayesian methods such as the Gibbs Sampler (a standard MCMC simulation method) are used to estimate the sources and the mixing matrix in the presence of noise.

I.I.D. Gaussian noise was added to the observations, which resulted in an SNR of about 16 dB. The mixing matrix used is given by A = [0.4000 0.8315 0.5657; -0.6928 -0.3444 0.5657].

7) Conclusion

In this project, we have investigated the use of different bases and overcomplete dictionaries in Blind Audio Source Separation. A Bayesian approach based on Gibbs Sampling was used to estimate the sources in the transform domain, the mixing matrix A and the noise standard deviation sigma. Various transforms were applied on different sets of signals and they yielded vastly diverse results. Sparsity of the sources was a central theme of the whole project and was found to be integral to the source separation algorithm’s performance.

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