SPEECH RECOGNITION BY SELECTING AND REFINING HOT WORDS

• US 20180330717A1
• Filed: 05/11/2017
• Published: 11/15/2018
• Est. Priority Date: 05/11/2017
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Jin, Feng, Liu, Wen, Ma, Li Jun, Zhu, Peng Cheng PP, Qin, Yong, Shi, Qin, Zhang, Shi Lei
• Granted Patent: US 10,607,601 B2
• Time in Patent Office: Days
• CPC Class Codes: G10L 15/12 using dynamic programming techniques, e.g. dynamic time warping [DTW]
• CPC Class Codes: G10L 15/1815 Semantic context, e.g. disambiguation of the recognition hypotheses based on word meaning
• CPC Class Codes: G10L 15/187 Phonemic context, e.g. pronunciation rules, phonotactical constraints or phoneme n-grams
• CPC Class Codes: G10L 15/197 Probabilistic grammars, e.g. word n-grams
• CPC Class Codes: G10L 2015/088 Word spotting

Abstract

Speech recognition is performed by receiving a speech signal that includes spoken phones. A dynamic time warping procedure is applied to the received speech signal to generate a time-warped signal. The time-warped signal is compared to a plurality of stored reference patterns to identify a set of stored reference patterns that are most similar to the time-warped signal. A candidate hot word is selected from a list using the identified set of stored reference patterns. The selection of the candidate hot word is then refined.

Claims

1. A computer-implemented method for performing speech recognition, the method comprising:

receiving, by a computer, a speech signal including one or more spoken phones;

applying, by the computer, a dynamic time warping procedure to the received speech signal to generate a time-warped signal;

comparing, by the computer, the time-warped signal to a plurality of stored reference patterns to determine a set of similarity values corresponding to the plurality of stored reference patterns, wherein each similarity value indicates a similarity level between the time-warped signal and each reference pattern;

identifying, by the computer, a reference pattern among of the plurality of stored reference patterns that has a smallest similarity value;

selecting, by the computer, a candidate hot word from a list of candidate hot words that correspond to the identified reference pattern;

determining, by the computer, another hot word having a greater probability of occurrence than the candidate hot word; and

refining, by the computer, the selection of the candidate hot word based on the said determining.

2. The computer-implemented method of claim 1 wherein the refining, by the computer, of the selection of the candidate hot word is performed using at least one of:

a set of n-gram information, a semantic analysis of a named entity, or a set of Gaussian components.

3. The computer-implemented method of claim 2 wherein the refining, by the computer, of the selection of the candidate hot word is performed by evaluating a probability of occurrence of the identified candidate hot word.

4. The computer-implemented method of claim 3 wherein the refining, by the computer, of the selection of the candidate hot word includes changing the identified candidate hot word to the another candidate hot word having the greater probability of occurrence than the identified candidate hot word.

5. The computer-implemented method of claim 1 wherein the comparing, by the computer, of the time-warped signal to a plurality of stored reference patterns includes using an acoustic similarity matrix that includes the set of similarity values.

6. The computer-implemented method of claim 5 wherein the selecting, by the computer, of a candidate hot word from a list of candidate hot words further comprises generating the list of candidate hot words using the acoustic similarity matrix.

7. The computer-implemented method of claim 1 wherein the selecting, by the computer, of a candidate hot word from a list of candidate hot words further comprises generating the list of candidate hot words from an electronically searchable dictionary.

8. The computer-implemented method of claim 1, wherein the method is provided as a service in a cloud environment.

9. A computer program product for performing speech recognition, the computer program product comprising a computer-readable storage medium having a computer-readable program stored therein, wherein the computer-readable program, when executed on a computing device including at least one processor, causes the at least one processor to:

receive a speech signal including one or more spoken phones;

apply a dynamic time warping procedure to the received speech signal to generate a time-warped signal;

compare the time-warped signal to a plurality of stored reference patterns to determine a set of similarity values corresponding to the plurality of stored reference patterns, wherein each similarity value indicates a similarity level between the time-warped signal and each reference pattern;

identify a reference pattern among of the plurality of stored reference patterns that has a smallest similarity value;

select a candidate hot word from a list of candidate hot words that correspond to the identified reference pattern;

determine another hot word having a greater probability of occurrence than the candidate hot word; and

refine the selection of the candidate hot word based on the said determination.

10. The computer program product of claim 9 wherein the refining is performed using at least one of:

a set of n-gram information, a semantic analysis of a named entity, or a set of Gaussian components.

11. The computer program product of claim 10 wherein the refining is performed by evaluating a probability of occurrence of the identified candidate hot word.

12. The computer program product of claim 11 wherein the computer-readable program, when executed on a computing device including at least one processor, causes the at least one processor to refine the selection by changing the identified candidate hot word to the another candidate hot word having the greater probability of occurrence than the identified candidate hot word.

13. The computer program product of claim 9 wherein the comparing is performed using an acoustic similarity matrix that includes the set of similarity values.

14. The computer program product of claim 13 wherein the selecting further comprises generating the list of candidate hot words using the acoustic similarity matrix.

15. The computer program product of claim 9 wherein the selecting further comprises generating the list of candidate hot words from an electronically searchable dictionary.

16. An apparatus for performing speech recognition, the apparatus comprising:

at least one processor; and

a memory coupled to the at least one processor, wherein the memory comprises program instructions which, when executed by the at least one processor, cause the at least one processor to;

receive a speech signal including one or more spoken phones;

apply a dynamic time warping procedure to the received speech signal to generate a time-warped signal;

compare the time-warped signal to a plurality of stored reference patterns to determine a set of similarity values corresponding to the plurality of stored reference patterns, wherein each similarity value indicates a similarity level between the time-warped signal and each reference pattern;

identify a reference pattern among of the plurality of stored reference patterns that has a smallest similarity value;

select a candidate hot word from a list of candidate hot words that correspond to the identified reference pattern;

determine another hot word having a greater probability of occurrence than the candidate hot word; and

refine the selection of the candidate hot word based on the said determination.

17. The apparatus of claim 16 further configured for performing the refining using at least one of:

a set of n-gram information, a semantic analysis of a named entity, or a set of Gaussian components.

18. The apparatus of claim 17 further configured for performing the refining by evaluating a probability of occurrence of the identified candidate hot word.

19. The apparatus of claim 18 further configured for performing the refining by changing the identified candidate hot word to the another candidate hot word having the greater probability of occurrence than the identified candidate hot word.

20. The apparatus of claim 16 further configured for performing the comparing using an acoustic similarity matrix that includes the set of similarity values.