System and method for modeless large vocabulary speech recognition

Abstract

A modeless large vocabulary continuous speech recognition system is provided that represents an input utterance as a sequence of input vectors. The system includes a common library of acoustic model states for arrangement in sequences that form acoustic models. Each acoustic model is composed of a sequence of segment models and each segment model is composed of a sequence of model states. An input processor compares each vector in a sequence of input vectors to a set of model states in the common library to produce a match score for each model state in the set, reflecting the likelihood that a state is represented by a vector. The system also includes a plurality of recognition modules and associated recognition grammars. The recognition modules operate in parallel and use the match scores with the acoustic models to determine at least one recognition result in each of the recognition modules. The recognition modules includes a dictation module for producing at least one probable dictation recognition result, a select module for recognizing a portion of visually displayed text for processing with a command, and a command module for producing at least one probable command recognition result. An arbitrator uses an arbitration algorithm and a score ordered queue of recognition results, together with their associated recognition modules, to compare the recognition results of the recognition modules to select at least one system recognition result.