GRAMMARS FOR SPEECH RECOGNITION

摘要

Pre-computed context-dependent phoneme representations of a number of constituents of a grammar are processed dynamically by a speech recognizer. The approach provides a configurable tradeoff between data size and recognition-time computation. This tradeoff can be obtained without sacrificing recognition accuracy, and in particular, allows full modeling of all cross-word phoneme contexts. In one aspect of the invention, a specification of a grammar is processed. This specification includes specifications of a number of constituents of the grammar. A first subset of the constituents of the grammar are selected, and the remaining of the constituents form a second subset. For each of the constituents in the first subset the method first includes processing the specification of the constituent to form a first processed representation that defines sequences of elements that are associated with that constituent and that includes words and references to constituents in the first subset. Forming the first processed representation of each constituent includes expanding references to constituents, in the second subset according to the specifications of those constituents, and retaining references to constituents in the first subset without expanding said references.