Evaluation of Spectral Tilt Measures for Sentence Prominence Under Different Noise Conditions

Spectral tilt has been suggested to be a correlate of prominence in speech, although several studies have not replicated this empirically. This may be partially due to the lack of a standard method for tilt estimation from speech, rendering interpretations and comparisons between studies difficult. In addition, little is known about the performance of tilt estimators for prominence detection in the presence of noise. In this work, we investigate and compare several standard tilt measures on quantifying prominence in spoken Dutch and under different levels of additive noise. We also compare these measures with other acoustic correlates of prominence, namely, energy, F0, and duration. Our results provide further empirical support for the finding that tilt is a systematic correlate of prominence, at least in Dutch, even though energy, F0, and duration appear still to be more robust features for the task. In addition, our results show that there are notable differences between different tilt estimators in their ability to discriminate prominent words from non-prominent ones in different levels of noise.