DYNAMIC THRESHOLDS FOR ALWAYS LISTENING SPEECH TRIGGER

• US 20160077794A1
• Filed: 08/24/2015
• Published: 03/17/2016
• Est. Priority Date: 09/12/2014
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Kim, Yoon, Gruber, Thomas R., Bridle, John
• Granted Patent: US 10,789,041 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 3/165 Management of the audio stream, e.g. setting of volume, audio stream path
• CPC Class Codes: G06F 3/167 Audio in a user interface, e.g. using voice commands for navigating, audio feedback
• CPC Class Codes: G10L 15/20 Speech recognition techniques specially adapted for robustness in adverse environments, e.g. in noise, of stress induced speech G10L21/02 takes precedence
• CPC Class Codes: G10L 15/22 Procedures used during a speech recognition process, e.g. man-machine dialogue
• CPC Class Codes: G10L 2015/088 Word spotting
• CPC Class Codes: G10L 2015/223 Execution procedure of a spoken command
• CPC Class Codes: G10L 2015/226 using non-speech characteristics

Abstract

Systems and processes are disclosed for dynamically adjusting a speech trigger threshold, which can be used in triggering a virtual assistant. Audio input can be received via a microphone. The received audio input can be sampled, and a confidence level can be determined of whether the sampled audio input includes a portion of a spoken trigger. In response to the confidence level exceeding a threshold, a virtual assistant can be triggered to receive a user command from the audio input. The threshold can be dynamically adjusted in response to perceived events (e.g., events indicating a user may be more or less likely to initiate speech interactions, events indicating a trigger may be difficult to detect, events indicating a trigger was missed, etc.), thereby minimizing both missed triggers and false positive triggering events.

Claims

1. A method for dynamically adjusting a speech trigger threshold, the method comprising:

at an electronic device having a processor and memory;

receiving audio input via a microphone;

sampling the received audio input;

determining a confidence level that the sampled audio input comprises a portion of a spoken trigger; and

in response to the confidence level exceeding a threshold, triggering a virtual assistant to receive a user command from the audio input;

wherein the threshold is dynamically adjusted in response to a perceived event.

2. The method of claim 1, wherein triggering the virtual assistant comprises initiating a virtual assistant session with a user.

3. The method of claim 1, further comprising:

determining a user intent based on the received user command; and

executing a command associated with the determined user intent.

4. The method of claim 1, further comprising:

lowering the threshold in response to the perceived event.

5. The method of claim 4, wherein the perceived event comprises determining, from a prior sampling of the audio input, a confidence level that the prior sampled audio input comprises a portion of the spoken trigger;

wherein the confidence level for the prior sampled audio input is within a predetermined range of the threshold without exceeding the threshold.

6. The method of claim 1, wherein the perceived event comprises detecting display of content associated with the virtual assistant.

7. The method of claim 1, wherein the perceived event comprises detecting that the virtual assistant is active.

8. The method of claim 1, wherein the perceived event comprises detecting a user'"'"'s proximity.

9. The method of claim 8, wherein the user'"'"'s proximity is detected based on a sound profile comprising sounds associated with human presence.

10. The method of claim 8, wherein the user'"'"'s proximity is detected at the electronic device and at least one other device, and the threshold is lowered at the electronic device based on closer user proximity to the electronic device than the at least one other device.

11. The method of claim 1, wherein the perceived event comprises detected motion.

12. The method of claim 1, wherein the perceived event comprises receiving a notification.

13. The method of claim 1, wherein the perceived event comprises a time of day or a scheduled calendar event.

14. The method of claim 1, wherein the perceived event comprises detecting an actionable user command in the sampled audio input.

15. The method of claim 1, further comprising:

raising the threshold in response to the perceived event.

16. The method of claim 1, wherein the perceived event comprises detecting a user command to dismiss the virtual assistant.

17. The method of claim 1, wherein the perceived event comprises detecting proximity of an object to the electronic device.

18. The method of claim 1, wherein the perceived event comprises detecting absence of a user.

19. The method of claim 1, wherein the perceived event comprises detecting a do not disturb setting associated with the electronic device.

20. The method of claim 1, wherein the threshold is restored to a predetermined level after a predetermined time has elapsed.

21. The method of claim 20, wherein the predetermined level is adjusted over time based on usage.

22. The method of claim 1, further comprising:

in response to receiving a notification, triggering the virtual assistant to receive a user command from the audio input.

23. The method of claim 22, wherein the virtual assistant is triggered without detecting receipt of the spoken trigger.

24. A non-transitory computer-readable storage medium comprising computer-executable instructions for:

receiving audio input via a microphone;

sampling the received audio input;

determining a confidence level that the sampled audio input comprises a portion of a spoken trigger; and

in response to the confidence level exceeding a threshold, triggering a virtual assistant to receive a user command from the audio input;

wherein the threshold is dynamically adjusted in response to a perceived event.

25. A system comprising:

one or more processors;

memory; and

one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including instructions for;

receiving audio input via a microphone;

sampling the received audio input;

determining a confidence level that the sampled audio input comprises a portion of a spoken trigger; and

in response to the confidence level exceeding a threshold, triggering a virtual assistant to receive a user command from the audio input;

wherein the threshold is dynamically adjusted in response to a perceived event.