A Two-stage Approach to Speech Bandwidth Extension
Abstract
Algorithms for speech bandwidth extension (BWE) may work in either the time domain or the frequency domain. Time-domain methods often do not sufficiently recover the high-frequency content of speech signals; frequency-domain methods are better at recovering the spectral envelope, but have difficulty reconstructing the details of the waveform. In this paper, we propose a two-stage approach for BWE, which enjoys the advantages of both time- and frequency-domain methods. The first stage is a frequency-domain neural network,