A novel tonality estimation method of spectral components for audio coding applications.

Abstract

A novel algorithm providing adequate tonality estimates for constant and modulated sinusoidal components was developed. The proposed algorithm was combined with the MPEG psychoacoustic model 2 in order to verify whether replacing the standard tonality estimator with the proposed one leads to a more reliable estimate of hearing threshold. It was verified whether the proposed tonality estimation algorithm may be used as a basis for detecting the signal bands containing only a noise‐like component that can be encoded according to the perceptual noise substitution technique. Subsequently, it was proved that it is possible to estimate the tonality of unmodulated or frequency‐modulated sinusoidal components of audio signals through the comparison of their instantaneous frequency variations determined employing both an estimator processing spectral amplitude samples and an estimator processing spectral phase samples. It was also revealed that distortions introduced during perceptual audio coding may be effectively limited employing the proposed tonality estimation algorithm. In order to fully explore the benefits of the proposed method for coding applications, the listening tests were performed in accordance with the ITU‐T BS.1534 recommendation. [Research partially funded by the Polish Ministry of Science and Higher Education within Grants Nos. PBZ‐MNiSW‐02‐II‐2007 and No. N N517 378736.]