METHOD FOR EXPANDING AUDIO SIGNAL BANDWIDTH

A method expands a bandwidth of an audio signal by determining a magnitude time-frequency representation |G(ω, t) for example audio signals g(t). A set of frequency marginal probabilities PG(ω|z) 221 are estimated from |G(ω, t)|, and a magnitude time-frequency representation |X(ω, t)| is determined from an input signal audio signal x(t). Probabilities P(z), PX(z) and PX(t|z) are determined using PG(ω|z)|X(ω, t)|. |Ŷ(ω, t)| is reconstructed according to PzPX(z)PG(ω|z)PX(t|z), and |Ŷ(ω, t)| is transformed to a time domain to obtain a high-quality output audio signal ŷ(t) corresponding to the input audio signal x(t).