Speaker verification methods and apparatus

Abstract

One aspect includes determining validity of an identity asserted by a speaker using a voice print associated with a user whose identity the speaker is asserting, the voice print obtained from characteristic features of at least one first voice signal obtained from the user uttering at least one enrollment utterance including at least one enrollment word by obtaining a second voice signal of the speaker uttering at least one challenge utterance that includes at least one word not in the at least one enrollment utterance, obtaining at least one characteristic feature from the second voice signal, comparing the at least one characteristic feature with at least a portion of the voice print to determine a similarity between the at least one characteristic feature and the at least a portion of the voice print, and determining whether the speaker is the user based, at least in part, on the similarity.

What is claimed is: 
     
         1 - 30 . (canceled) 
     
     
         31 . A method for verifying a speaker's identity using a voice print associated with a user whose identity the speaker is asserting, the voice print obtained from the user's utterance of at least one enrollment utterance including at least one enrollment word, the method comprising:
 determining, using at least one hardware processor, whether the speaker is the user based, at least in part, on the voice print and a voice signal of the speaker uttering at least one challenge utterance,   wherein the at least one challenge utterance includes at least one word that was not in the at least one enrollment utterance.   
     
     
         32 . The method of  claim 31 , wherein the method further comprises obtaining the voice signal of the speaker uttering the at least one challenge utterance. 
     
     
         33 . The method of  claim 32 , wherein obtaining the voice signal of the speaker uttering the at least one challenge utterance includes obtaining at least one challenge utterance consisting preponderantly of words not used in the at least one enrollment utterance. 
     
     
         34 . The method of claim  30 , wherein obtaining the voice signal of the speaker uttering the at least one challenge utterance includes obtaining at least one challenge utterance consisting substantially of words not used in the at least one enrollment utterance. 
     
     
         35 . The method of  claim 32 , wherein obtaining the voice signal of the speaker uttering the at least one challenge utterance includes obtaining at least one challenge utterance selected from a challenge vocabulary comprising a plurality of challenge words, wherein the challenge vocabulary includes words having substantial phonetic overlap with the at least one word used in the at least one enrollment utterance. 
     
     
         36 . The method of  claim 35 , wherein each of the plurality of words in the challenge vocabulary has at least one syllable that rhymes with at least one syllable of at least one word used in the at least one enrollment utterance. 
     
     
         37 . The method of  claim 31 , further comprising performing automatic speech recognition on the voice signal of the speaker to verify that the speaker spoke the at least one word in the at least one challenge utterance. 
     
     
         38 . At least one computer readable medium encoded with at least one program that, when executed by at least one hardware processor, causes the at least one hardware processor to perform acts for verifying a speaker's identity using a voice print associated with a user whose identity the speaker is asserting, the voice print obtained from the user's utterance of at least one enrollment utterance including at least one enrollment word, the acts comprising:
 determining whether the speaker is the user based, at least in part, on the voice print and a voice signal of the speaker uttering at least one challenge utterance,   wherein the at least one challenge utterance includes at least one word that was not in the at least one enrollment utterance.   
     
     
         39 . The at least one computer readable medium of  claim 38 , wherein the at least one program, when executed by the at least one hardware processor, causes the at least one hardware processor to perform an act of obtaining the voice signal of the speaker uttering at least one challenge utterance. 
     
     
         40 . The at least one computer readable medium of  claim 39 , wherein obtaining the voice signal of the speaker uttering the at least one challenge utterance includes obtaining at least one challenge utterance consisting preponderantly of words not used in the at least one enrollment utterance. 
     
     
         41 . The at least one computer readable medium of  claim 39 , wherein obtaining the voice signal of the speaker uttering the at least one challenge utterance includes obtaining at least one challenge utterance consisting substantially of words not used in the at least one enrollment utterance. 
     
     
         42 . The at least one computer readable medium of  claim 39 , wherein obtaining the voice signal of the speaker uttering the at least one challenge utterance includes obtaining at least one challenge utterance selected from a challenge vocabulary comprising a plurality of challenge words, wherein the challenge vocabulary includes words having substantial phonetic overlap with the at least one enrollment word used in the at least one enrollment utterance. 
     
     
         43 . The at least one computer readable medium of  claim 39 , wherein the at least one program, when executed by the at least one hardware processor, causes the at least one hardware processor to perform automatic speech recognition on the voice signal of the speaker to verify that the speaker spoke the at least one word in the at least one challenge utterance. 
     
     
         44 . A speaker verification system comprising:
 at least one computer readable storage medium storing a voice print obtained from a user's utterance of at least one enrollment utterance; and   at least one controller, coupled to the at least one computer readable storage medium, configured to determine whether the speaker is the user based, at least in part, on the voice print and a voice signal of the speaker uttering at least one challenge utterance,   wherein the at least one challenge utterance includes at least one word that was not in the at least one enrollment utterance.   
     
     
         45 . The speaker verification system of  claim 44 , further comprising:
 a receiver configured to receive the voice signal of the speaker uttering the at least one challenge utterance,   wherein the receiver receives the voice signal of the speaker uttering the at least one challenge utterance consisting preponderantly of words not used in the at least one enrollment utterance.   
     
     
         46 . The speaker verification system of  claim 44 , further comprising:
 a receiver configured to receive the voice signal of the speaker uttering the at least one challenge utterance,   wherein the receiver receives the voice signal of the speaker uttering the at least one challenge utterance consisting substantially of words not used in the at least one enrollment utterance.   
     
     
         47 . The speaker verification system of  claim 44 , further comprising:
 a receiver configured to receive the voice signal of the speaker uttering the at least one challenge utterance,   wherein the receiver receives the voice signal of the speaker uttering at least one challenge utterance selected from a challenge vocabulary comprising a plurality of challenge words, wherein the challenge vocabulary includes words having substantial phonetic overlap with the at least one enrollment word used in the at least one enrollment utterance.   
     
     
         48 . The speaker verification system of  claim 47 , wherein each of the plurality of words in the challenge vocabulary has at least one syllable that rhymes with at least one syllable of at least one word used in the at least one enrollment utterance. 
     
     
         49 . The speaker verification system of  claim 44 , further comprising:
 a receiver configured to receive the voice signal of the speaker uttering the at least one challenge utterance,   wherein the at least one enrollment word is selected from an enrollment vocabulary, and wherein the receiver receives the voice signal of the speaker uttering at least one challenge utterance selected from a challenge vocabulary comprising a plurality of challenge words, and wherein the challenge vocabulary includes more words than the enrollment vocabulary.   
     
     
         50 . The speaker verification system of  claim 44 , wherein each distinct word used in the at least one enrollment utterance has a plurality of corresponding words in the challenge vocabulary, each having phonetic overlap with the corresponding word in the at least one enrollment utterance.