Method and apparatus for dynamic adaptation of a large vocabulary speech recognition system and for use of constraints from a database in a large vocabulary speech recognition system

摘要

The lexical network of a large-vocabulary speech recognition system is structured to effectuate the rapid and efficient addition of words to the system's active vocabulary. The lexical network is structured to include Phonetic Constraint Nodes, which organize the inter-word phonetic information in the network, and Word Class Nodes which organize the syntactic semantic information in the network. Network fragments, corresponding to phoneme pronunciations and labeled to specify permitted interconnections to each other and to phonetic constraint nodes, are precompiled to facilitate the rapid generation of pronunciations for new words and thereby enhance the rapid addition of words to the vocabulary even during speech recognition. Functions defined in accordance with linguistic constraints may be utilized during recognition. Different language models and different vocabularies for different portions of a discourse may also be invoked depending, in part, on the discourse history.