Structural analysis of Chinese dialects and its experimental application to pronunciation assessment

摘要

The current situation of Chinese dialects is very complicated, not only because there are hundred kinds of dialects, sub-dialects and sub-sub-dialects, but also because many dialect speakers are speaking Mandarin with different regional accents affected by their dialects. If dialect utterances are represented acoustically, their acoustic features depend both on dialectal linguistic features and extra-linguistic features such as the age, gender, micro-phone, etc. Then, the automatic pronunciation assessment of Chinese dialects becomes a challenging task. In this paper, we propose to analyze the dialect pronunciation by the structural representation, which was originally used to remove extra-linguistic information from speech. After collecting the utterances of some selected Chinese written characters, the pronunciation structures are built for dialect speakers and their pronunciations are compared by the distances among the structures. Then with the dialect utterances of 16 native dialect speakers, some experiments are carried out to analyze their pronunciations using the structures and linguistically-reasonable results are obtained. At last, by comparing the pronunciation structures of dialect speakers with those of two standard Mandarin speakers, the pronunciation similarity orders of the characters are obtained. Through these experiments, our approach is proved again that it works well in extracting the linguistic features from dialect utterances and shows high independence of the extra-linguistic features.