Corpus-based Mandarin speech synthesis with contextual syllabic units based on phonetic properties

This paper describes an improved concatenative synthesis module for a Chinese text-to-speech system. The concatenated segments are on-line selected from a designed speech corpus that is precisely segmented with an improved version of HMMs. The selection criteria are the prosodic and contextual similarities between the units and the desired targets from the previous module of the TTS system. The TD-PSOLA modifies the prosodic parameters of the selected units, and three methods for unit concatenation are performed according to the types of the syllabic junctures. These types are classified with the knowledge from the phonetic observations of large amounts of speech data. The output speech is remarkably fluent and natural because the coarticulation effects cross syllabic boundaries are well modeled and less prosodic modification is needed for the TD-PSOLA