Speech end-pointer

• US 20060287859A1
• Filed: 06/15/2005
• Published: 12/21/2006
• Est. Priority Date: 06/15/2005
• Status: Active Grant

• Current Assignee: Blackberry Limited
• Original Assignee: Harman Becker Automotive Systems Wavemakers Inc (Blackberry Limited)
• Inventors: Hetherington, Phil, Escott, Alex
• Granted Patent: US 8,170,875 B2
• Time in Patent Office: Days
• US Class Current: 704/260
• CPC Class Codes: G10L 25/87 Detection of discrete points within a voice signal

Abstract

A rule-based end-pointer isolates spoken utterances contained within an audio stream from background noise and non-speech transients. The rule-based end-pointer includes a plurality of rules to determine the beginning and/or end of a spoken utterance based on various speech characteristics. The rules may analyze an audio stream or a portion of an audio stream based upon an event, a combination of events, the duration of an event, or a duration relative to an event. The rules may be manually or dynamically customized depending upon factors that may include characteristics of the audio stream itself, an expected response contained within the audio stream, or environmental conditions.

Claims

1. An end-pointer that determines at least one of a beginning and end of an audio speech segment, the end-pointer comprising:

a voice triggering module that identifies a portion of an audio stream comprising speech event; and

a rule module in communication with the voice triggering module, the rule module comprising a plurality of time duration rules that analyze at least part of the audio stream to determine whether an audio speech segment relative to the speech event is within an audio endpoint.

2. The end-pointer of claim 1, where the voice triggering module identifies a vowel.

3. The end-pointer of claim 1, where the voice triggering module identifies an S or X sound.

4. The end-pointer of claim 1, where the portion of the audio stream comprises a frame.

5. The end-pointer of claim 1, where the rule module analyzes a lack of energy in the portion of the audio stream.

6. The end-pointer of claim 1, where the rule module analyzes an energy in the portion of the audio stream.

7. The end-pointer of claim 1, where the rule module analyzes an elapsed time in the portion of the audio stream.

8. The end-pointer of claim 1, where the rule module analyzes a predetermined number of plosives in the portion of the audio stream.

9. The end-pointer of claim 1, where the rule module detects the beginning and end of the audio speech segment.

10. The end-pointer of claim 1, further comprising an energy detector module.

11. The end-pointer of claim 1, further comprising a processing environment in communication with a microphone input, a processing unit, and a memory, where the rule module resides within the memory.

12. A method of determining at least one of a beginning and end of an audio speech segment utilizing an end-pointer with a plurality of decision rules, the method comprising:

receiving a portion of an audio stream;

determining whether the portion of the audio stream includes a triggering characteristic; and

applying at least one time duration decision rule to a portion of the audio stream relative to the triggering characteristic to determine whether the portion of the audio stream is within an audio endpoint.

13. The method of claim 12, where the decision rule is applied to the portion of the audio stream that includes the triggering characteristic.

14. The method of claim 12, where the decision rule is applied to a different portion of the audio stream than the portion that includes the triggering characteristic.

15. The method of claim 12, where the triggering characteristic is a vowel.

16. The method of claim 12, where the triggering characteristic is an S or X sound.

17. The method of claim 12, where the portion of the audio stream is a frame.

18. The method of claim 12, where the rule module analyzes a lack of energy in the portion of the audio stream.

19. The method of claim 12, where the rule module analyzes an energy in the portion of the audio stream.

20. The method of claim 12, where the rule module analyzes an elapsed time in the portion of the audio stream.

21. The method of claim 12, where the rule module analyzes a predetermined number of plosives in the portion of the audio stream.

22. The method of claim 12, where the rule module detects the beginning and end of the potential speech segment.

23. An end-pointer that determines at least one of a beginning and end of an audio speech segment in an audio stream, the end-pointer comprising:

an end-pointer module comprising a plurality of time duration rules that analyze at least one dynamic aspect of the audio stream to determine whether the audio speech segment is within an audio endpoint; and

a memory in communication with the end-pointer module, the memory configured to store profile information that alters a time duration of one or more of the plurality of rules.

24. The end-pointer of claim 23, where the dynamic aspect of the audio stream comprises at least one characteristic of a speaker.

25. The end-pointer of claim 24, where the characteristic of the speaker comprises a pace of speaking of the speaker.

26. The end-pointer of claim 23, where the dynamic aspect of the audio stream comprises background noise in the audio stream.

27. The end-pointer of claim 23, where the dynamic aspect of the audio stream comprises an expected sound in the audio stream.

28. The end-pointer of claim 27, where the expected sound comprises at least one expected answer to a question posed to a speaker.

29. The end-pointer of claim 23, further comprising a processing environment in communication with a microphone input, a processing unit, and a memory, where the end-pointer module resides within the memory.

30. An end-pointer that determines at least one of a beginning and end of an audio speech segment in an audio stream, the end-pointer comprising:

a voice triggering module that identifies a portion of an audio stream comprising a periodic audio signal; and

an end-pointer module varying an amount of the audio stream input to a recognition device based on a plurality of rules,

where the plurality of rules include time duration rules to determine whether a portion of an audio stream relative to the periodic audio signal is within an audio endpoint.

31. The end-pointer of claim 30, where the recognition device is an automatic speech recognition device.

32. A signal-bearing medium having software that determines at least one of a beginning and end of an audio speech segment, comprising:

a detector that converts sound waves into electrical signals;

a triggering logic that analyzes a periodicity of the electrical signals; and

a signal analysis logic that analyzes a variable portion of the sound waves that are associated with the audio speech segment to determine at least one of a beginning and end of the audio speech segment.

33. The signal-bearing medium of claim 32, where the signal analysis logic analyzes a time duration before a voiced speech sound.

34. The signal-bearing medium of claim 32, where the signal analysis logic analyzes a time duration after a voiced speech sound.

35. The signal-bearing medium of claim 32, where the signal analysis logic analyzes a number of transition before or after a voiced speech sound.

36. The signal-bearing medium of claim 32, where the signal analysis logic analyzes a duration of continuous silence before a voiced speech sound.

37. The signal-bearing medium of claim 32, where the signal analysis logic analyzes a duration of continuous silence after a voiced speech sound.

38. The signal-bearing medium of claim 32, where the signal analysis logic is coupled to a vehicle.

39. The signal bearing medium of claim 32, where the signal analysis logic is coupled to an audio system.