Comparative performance of spectral subtraction and HMM-based speech enhancement strategies with application to hearing and design

We have investigated effectiveness of several HMM-based speech enhancement strategies in the hearing aid context and compared their performance to a traditional method based on spectral subtraction (also called Wiener filtering). The performance of the various systems has been evaluated using several types of noise likely to be encountered by hearing impaired listeners. Both the objective and subjective evaluations demonstrate consistent superiority of the HMM-based enhancement methods over the spectral subtraction method. The superiority is more evident for sentences contaminated by nonstationary noises at low input SNRs