title: The design and testing of a noise reduction algorithm based on spectral subtraction.
abstract: Three noise reduction algorithms based on amplitude subtraction were designed and used to process speech mixed with babble noise in two signal-to-noise ratios. The estimation of the noise-magnitude spectrum was performed with a novel synchro method, which exploits specific characteristics of the speech signal. The unprocessed and processed signals were evaluated psychoacoustically by means of a four-alternative-forced choice test with monosyllabic words (minimal pairs) in carrier phrases. The testing was carried out on groups of normally hearing and hearing-impaired subjects and the long-term power spectra of the processed signals were shaped to be essentially identical with those from the corresponding unprocessed signals. For the hearing-impaired subjects all signals were spectrally shaped according to the POGO-fitting rule. None of the algorithms improved speech intelligibility for any group of listeners and no change in the overall pattern of confusion was observed.
authors.affiliation: Oticon Research Unit, Eriksholm, Snekkersten, Denmark.
authors.forename: C
authors.initials: C
authors.lastname: Elberling
authors.forename: C
authors.initials: C
authors.lastname: Ludvigsen
authors.forename: G
authors.initials: G
authors.lastname: Keidser
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D000465:Algorithms; D005260:Female; D006309:Hearing; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis*; D006320:Hearing Tests; D006801:Humans; D008297:Male; D008875:Middle Aged; D009622:Noise / Q000009:adverse effects; D011571:Psychoacoustics; D013018:Sound Spectrography; D013063:Speech Discrimination Tests; D013067:Speech Perception