Application of auditory masking in improved multiband excitation model

Modifications to improve the performance of the improved multiband excitation (IMBE) model in coding narrow-band speech are presented in this paper. The first modification is based on the phenomenon of auditory masking which helps the model to focus on the perceptual aspect of the coder by eliminating components that are inaudible to human ears during the analysis process of the IMBE model. In addition, a spectral amplitude enhancement stage is added. Preliminary results indicate that the proposed modifications improve the objective and subjective performances of the IMBE model in coding narrow-band speech at 4.15 kbps.