Interactive computer system recognizing spoken commands

Abstract

An interactive computer system having a processor executing a target computer program, and having a speech recognizer for converting an utterance into a command signal for the target computer program. The target computer program has a series of active program states occurring over a series of time periods. At least a first active-state image is displayed for a first active state occurring during a first time period. At least one object displayed in the first active-state image is identified, and a list of one or more first active-state commands identifying functions which can be performed in the first active state of the target computer program is generated from the identified object. A first active-state vocabulary of acoustic command models for the first active state comprises the acoustic command models from a system vocabulary representing the first active-state commands. A speech recognizer measures the value of at least one feature of an utterance during each of a series of successive time intervals within the first time period to produce a series of feature signals. The measured feature signals are compared to each of the acoustic command models in the first active-state vocabulary to generate a match score for the utterance and each acoustic command model. The speech recognizer outputs a command signal corresponding to the command model from the first active-state vocabulary having the best match score.