Patent ID: 7574360

Claim:
A Chinese Text-To-Speech (TTS) synthesis system comprising: a computer system implementing a word pre-processing module configured to receive a text defining a Chinese sentence, a unit selection module, a speech generation module, an automatic speech unit-parsing module, and a speech output module; and a corpus stored in database accessible by said computer system; wherein said unit selection module comprises: a probabilistic context free grammar (PCFG) parser, a latent semantic indexing (LSI) module, and a modified variable-length unit selection scheme; said PCFG parser parses said Chinese sentence to obtain a context free grammar (CFG) of said Chinese sentence as its target unit; said automatic speech unit-parsing module automatically labels the location of nodes of every syllable of the Chinese sentence; said LSI module estimates the structural distance between the candidate synthesis units and the target unit in said corpus, and conducts a vectorization for estimating the structural distance, said vectorization transforming all the corpus words into ordered vectors and storing them in a CFG data matrix in the dimension of RxQ, wherein R stands for a number of grammar rules in a grammar G of the entire PCFG, and Q stands for the number of sentences in the corpus; and through said modified variable-length unit selection scheme, tagged with a dynamic program algorithm, the units are searched to find the best synthesis unit concatenation sequence of said Chinese sentence; wherein said speech output module is adapted to generate a synthesized speech output according to said concatenation sequence; and wherein a Chomsky Normal Form is used to simplify and describe the PCFG parser and to simplify the estimation of the structural distance.