Improvement of MBSD by scaling noise masking threshold and correlation analysis with MOS difference instead of MOS

The modified bark spectral distortion (MBSD) used for an objective speech quality measure, was presented previously. The MBSD measure estimates speech distortion in the loudness domain taking into account the noise masking threshold in order to include only audible distortions in the calculation of the distortion measure. Preliminary simulation results have shown improvement of the MBSD over the conventional BSD. The performance of the MBSD is improved by scaling noise masking threshold and comparing it to ITU-T Recommendation P.861 and MNB measures. Correlation analysis with MOS difference instead of MOS has been examined in order to evaluate objective speech quality measures.