A system and apparatus for recognizing speech
AssigneeAT&T Corp.
InventorsSteven Phillips, Anne Rogers
Life of this patent
Estimating the term…
Abstract
A continuous, speaker independent, speech recognition method and system for recognizing a variety of vocabulary input signals. A language model which is an implicit description of a graph consisting of a plurality of states and arcs is inputted into the system. An input speech signal, corresponding to a plurality of speech frames is received and processed using a shared memory multipurpose machine having a plurality of microprocessors working in parallel to produce a textual representation of the speech signal.
Claims30
A speech recognition method for recognizing a variety of speech inputs comprising the steps of:
- receiving a signal corresponding to a plurality of speech frames;
- inputting a language model in a general purpose shared memory machine having a plurality of processors wherein said model is an implicit description of a graph consisting of a plurality of states and arcs;
- assigning each state to at least one of said processors;
- and
- processing said states using said plurality of processors.
A general purpose speech recognition system for receiving a speech signal and producing a textual representation of said speech signal, said system capable of recognizing a variety of speech input, said recognition system comprising:
- a data processing machine having at least two microprocessors and a memory means;
- a speech signal inputted to said machine;
- means for receiving said speech signal and digitally sampling said signal at a predetermined rate resulting in a representation of said input signal as a series of speech frames;
- an inputted language model stored in said memory means, said model including models relating to probability distributions corresponding to a plurality of speech sounds;
- means responsive to said speech frame for producing a set of signals representative of said input speech frame, said means for producing including processing a Viterbi speech algorithm in parallel on said microprocessors, said algorithm mapping said speech frames to Hidden Markov models and producing a textual representation of said received speech signal based on likelihood calculations;
- and
- means for providing a representation of said speech signal.
A method of speech recognition having a plurality of active states, said method comprising the steps of:
- partitioning said plurality of active states to create one or more active state subsets, each of said subsets including a number of active states;
- assigning each of said active state subsets to one or a plurality of microprocessors included in a multiprocessor shared memory machine;
- determining active arcs associated with said active states;
- assigning said active arcs to a particular processor based on said assignment of said active states;
- performing a likelihood calculation for each of said active arcs;
- and
- pruning said active arcs based on said likelihood calculation such that said arcs having a likelihood calculation within a computed range are included in an active arc sublist.
Dependencies are inferred from the claim text.