MELHORAMENTO DO SINAL DE VOZ POR INIBIÇÃO LATERAL E MASCARAMENTO BINAURAL

Abstract

The human hearing system is capable to accomplish different tasks that would be useful in engineering applications. One of them is the ability to separate sound sources, allowing the listener to "focus" a single sound source in a noisy environment. Great investments have been made in the development of technologies applied to the voice recognition by machines in real environment. For that, different techniques of processing computational have been proposed, for reduction of the ambient noise and improvement of the signal desired in complex acoustic environment (cocktail party). The model of the human hearing system motivates those techniques in their different phases. In this work, we developed an algorithm to improve the processing speech signal based on the binaural hearing model. After receiving the mixed signals, for two microphones, the algorithm increases the intelligibility of the signal of larger energy of one of the receivers. Using two speakers and considering that each one is closer of one of the microphones, we made use of the concepts of lateral inhibition and binaural masking, to recover the signal of speech of larger energy of one of the receivers. The algorithm was developed in platform matlab and it was compared with another without use the lateral inhibition in the recovery of the desired signal. The results, appraised through the calculation of the relative error and of the scale MOS, showed that the use of the lateral inhibition in the recovery of the signal, improves the relative error between the desired signal and the recovered signal and consequently the quality of the recovered signal.