Continuous speech pattern recognizer

A method for recognizing a speech pattern as a string of predetermined reference words comprising the steps of:

• storing a set of signals representative of the time frame sequence of acoustic features of each reference word, said sequence having a beginning frame and an ending frame;
• producing a set of signals representative of the time frame sequence of acoustic features of the speech pattern;
• generating at least one reference word string responsive to the speech pattern acoustic feature signals and the reference word acoustic feature signals;
• and identifying the speech pattern as one of the generated reference word strings characterized in that said reference word string generation comprises:
• producing a set of signals identifying successive reference word levels;
• assigning a segment of the speech pattern to each successive level;
• for each level, time registering the level speech pattern segment feature signals with the feature signals of the reference words to produce level time registration speech pattern segment endframe signals and time registration correspondence signals for said reference words, and selecting reference word strings responsive to the time registration speech pattern endframe and time registration correspondence signals of the levels.

A speech analyzer for recognizing a speech pattern as a string of predetermined reference words comprising:

• means for storing a set of signals representative of the time frame sequence of acoustic features of each reference word from a beginning frame to an ending frame, means for producing a set of signals representative of the time frame sequence of acoustic features of the speech pattern from a beginning frame to a final frame;
• means responsive to the feature signals of said reference words and said speech pattern for generating at least one reference word string;
• and means for identifying the speech pattern as one of said generated reference word strings, said reference word string generating means comprising:
• means for generating a set of signals to identify successive levels of said reference words;
• means for assigning a segment of said speech pattern to each successive level, means operative at each successive level responsive to the reference word and speech pattern segment feature signals for dynamically time warping feature signals of each reference word with the feature signals of the speech pattern segment assigned to the level to produce signals representative of time registration path speech pattern endframes for said reference words and signals representative of the correspondence of the reference word and speech pattern segment feature signals on said time registration path;
• and means responsive to the time registration path speech pattern endframe and correspondence signals of the levels for selecting strings of reference words.

A method for recognizing a speech pattern as a string of predetermined reference words comprising the steps of:

• storing a set of signals representative of the time frame sequence of acoustic features of each reference word from a beginning frame to an ending frame;
• producing a set of signals representative of the time frame sequence of acoustic features of the speech from a beginning frame to a final frame;
• generating at least one reference word string responsive to the feature signals of the reference words and the feature signals of the speech pattern;
• and identifying the speech pattern as one of said generated reference word strings;
• the reference word string generating step comprising:
• generating a set of signals to identify successive levels of said reference words, assigning a segment of the speech pattern to each successive reference word level, at each reference word level dynamically time warping the feature signals of each reference word with the feature signals of the speech pattern segment assigned to the level to produce signals representative of time registration path speech pattern endframes for said reference word and signals representative of the correspondence of the reference word and speech pattern segment feature signals along the time registration paths, and selecting strings of reference words responsive to the time registration path speech pattern endframe and correspondence signals of the levels.