A Concatenative Speech Synthesis Method Using Context Dependent Phoneme Sequences with Variable Length as Search Units

摘要

A concatenative speech synthesis method using words and clustered triphones as search units has been proposed. Only 20% words in the sentences, however, satisfy the phoneme context as well as enough quantity in the speech database although most of the words in the sentences can be found in the speech database. So in this paper, we try to use context dependent phoneme sequences not bound by words and to concatenate the speech segments satisfying phoneme context. We produce synthesized speech by proposed method using four different size speech databases. The subjective evaluation on then-naturalness shows that 1) mean opinion score is 3.6, 2) enlargement of speech database more than 43.2 hours doesn't contribute the improvement in naturalness 3) the processing time of speech synthesis shows a little increase with enlargement of speech database.