A Preliminary Study on Quantitative Calculation of Prosodic Strength in Mandarin Speech

Prosodic strength refers to the relative prominence of each syllable in continuous speech. It used to be annotated at several degrees by perception, but perceptual annotation is highly subjective and cannot give continuous values that are potentially useful in speech technologies. This study proposed a method to estimate prosodic strength of each syllable in Mandarin continuous speech, by a linear combination of three acoustic measures, viz., normalized syllable duration, pitch span, and F0 deviation from the tone template. The validity of the method was verified by the relationship between the acoustically estimated prosodic strength and the perceptually labelled stress index, by the relationship between prosodic strength and POS class, and by the comparison on prosodic strengths of the same words in different focal conditions.