A harmonic bandwidth extension based on Gaussian mixture model

For conventional bandwidth extension, the spectral patching methods, such as spectral folding, spectral translation and non-linear processing, are employed to reconstruct high frequency signal, yet it leads to the spectral shifting between reconstructed and original signal, and does not retain the original harmonic relations. In this paper, a blind harmonic bandwidth extension method from wideband to super-wideband was proposed by estimating the energy of high frequency spectral envelope with Gaussian mixture model (GMM). Both the objective and subjective test results show that proposed algorithm performs better than conventional blind bandwidth extension algorithms.