  In this paper, a speech enhancement method based on noise compensation
performed on short time magnitude as well phase spectra is presented. Unlike
the conventional geometric approach (GA) to spectral subtraction (SS), here the
noise estimate to be subtracted from the noisy speech spectrum is proposed to
be determined by exploiting the low frequency regions of current frame of noisy
speech rather than depending only on the initial silence frames. This approach
gives the capability of tracking non-stationary noise thus resulting in a
non-stationary noise-driven geometric approach of spectral subtraction for
speech enhancement. The noise compensated magnitude spectrum from the GA step
is then recombined with unchanged phase of noisy speech spectrum and used in
phase compensation to obtain an enhanced complex spectrum, which is used to
produce an enhanced speech frame. Extensive simulations are carried out using
speech files available in the NOIZEUS database shows that the proposed method
consistently outperforms some of the recent methods of speech enhancement when
employed on the noisy speeches corrupted by street or babble noise at different
levels of SNR in terms of objective measures, spectrogram analysis and formal
subjective listening tests.
