Sound event detection

Patent metadata

Field	Value
Publication number	US-2016335488-A1
Application number	US-201514713619-A
Country	US
Kind code	A1
Filing date	May 15, 2015
Priority date	May 15, 2015
Publication date	Nov 17, 2016
Grant date	—

Abstract

A system and method for the use of sensors and processors of existing, distributed systems, operating individually or in cooperation with other systems, networks or cloud-based services to enhance the detection and classification of sound events in an environment (e.g., a home), while having low computational complexity. The system and method provides functions where the most relevant features that help in discriminating sounds are extracted from an audio signal and then classified depending on whether the extracted features correspond to a sound event that should result in a communication to a user. Threshold values and other variables can be determined by training on audio signals of known sounds in defined environments, and implemented to distinguish human and pet sounds from other sounds, and compensate for variations in the magnitude of the audio signal, different sizes and reverberation characteristics of the environment, and variations in microphone responses.

First claim

1 . An environmental data monitoring and reporting system, comprising:
a device sensor that detects sound in an area and generates an audio signal based on the detected sound; a device processor communicatively coupled to the device sensor, wherein the processor is configured to convert the audio signal received from the device sensor into low-resolution audio signal data and analyze the audio signal data, at the device processor level, to identify the detected sound as an area human or pet occupancy-related sound and provide a communication regarding the detected occupancy-related sound; and a device communication interface communicatively coupled to the device processor, wherein the communication interface is configured to send the communication regarding the detected occupancy-related sound, wherein the device sensor, device processor and device communication interface are integrated into a single premises management device.

2 . The system of claim 1 , wherein the processor is configured to:
perform a frequency domain conversion of the audio signal data and extract low-resolution feature vectors that distinguish detected sounds; determine state transition conditions by comparing the low-resolution feature vectors to threshold values that distinguish sound categories and generate outputs indicating occurrences of distinguished sound categories; and detect the occurrence of a sound category indicating an area human or pet occupancy and generating a user message in response.

3 . The system of claim 2 , further comprising a Fast Fourier Transform element, controlled by the processor, to perform the frequency domain conversion of the audio signal data, on a frame-by-frame basis.

4 . The system of claim 2 , further comprising:
a plurality of bandwidth filters, controlled by the processor, to divide the bands of the frequency domain conversion; a plurality of median filters, controlled by the processor, to filter a sample length of the divided bands; a plurality of range filters, controlled by the processor, to filter a range of the sample lengths; and a plurality of summers, controlled by the processor, to subtract a minimum sample range value from a maximum sample range value to calculate the plurality of low-resolution feature vectors that distinguish detected sounds, on a frame-by-frame basis.

5 . The system of claim 2 , further comprising:
a state classifier element, controlled by the processor, to determine the transition conditions by comparing the plurality of low-resolution feature vectors to threshold values and generate the outputs indicating the occurrences of distinguished sound categories, on a frame-by-frame basis.

6 . The system of claim 5 , wherein the processor is configured to train on audio signal data of known sound categories in defined areas to determine threshold values that distinguish sound categories and that compensate for audio signal data, area and sensor variations.

7 . The system of claim 2 , further comprising:
a detector element, controlled by the processor, to detect the occurrence of the sound category indicating an area human or pet occupancy; and the communication interface, controlled by the processor, to communicate a user message in response to the detected occurrence of the sound category indicating an area human or pet occupancy.

8 . The system of claim 7 , wherein the detector element is configured to analyze each output indicating an occurrence of a sound category as received to detect an output denoting an occurrence of the sound category indicating an area human or pet occupancy.

9 . The system of claim 7 , wherein the detector element is configured to analyze a set of outputs indicating occurrences of sound categories to detect the first output of the set denoting an occurrence of the sound category indicating an area human or pet occupancy.

10 . The system of claim 7 , wherein the detector element is configured to statistically analyze a set of outputs indicating occurrences of sound categories to detect a likelihood of an occurrence of the sound category indicating an area human or pet occupancy.

11 . An environmental data monitoring and reporting system, comprising:
a device sensor that detects a condition in an area and generates a signal based on the detected condition; a device processor communicatively coupled to the device sensor, wherein the processor is configured to convert the signal received from the sensor into low-resolution signal data and analyze the signal data, at the processor level, by:
performing a frequency domain conversion of the signal data and extracting low-resolution feature vectors that distinguish detected conditions,
comparing the low-resolution feature vectors to threshold values that distinguish condition categories,
generating outputs indicating occurrences of distinguished condition categories, and
detecting the occurrence of a condition category indicating an area human or pet occupancy and generating a user message in response; and
a device communication interface communicatively coupled to the device processor, wherein the communication interface is configured to send the user message regarding the detected occupancy-related condition, wherein the device sensor, device processor and device communication interface are integrated into a single premises management device.

12 . The system of claim 11 , further comprising:
a Fast Fourier Transform element, controlled by the processor, to perform the frequency domain conversion of the signal data; a plurality of bandwidth filters, controlled by the processor, to divide the bands of the frequency domain conversion; a plurality of median filters, controlled by the processor, to filter a sample length of the divided bands; a plurality of range filters, controlled by the processor, to filter a range of the sample lengths; and a plurality of summers, controlled by the processor, to subtract a minimum sample range value from a maximum sample range value to calculate the plurality of low-resolution feature vectors that distinguish detected conditions.

13 . The system of claim 11 , further comprising:
a state classifier element, controlled by the processor, to compare the plurality of low-resolution feature vectors to threshold values and generate the outputs indicating the occurrences of distinguished condition categories.

14 . The system of claim 13 , wherein the processor is configured to train on audio signal data of known condition categories in defined areas to determine threshold values that distinguish condition categories and that compensate for signal data, area and sensor variations.

15 . The system of claim 11 , further comprising:
a detector element, controlled by the processor, to detect the occurrence of the condition category indicating an area human or pet occupancy; and the communication interface, controlled by the processor, to communicate a user message in response to the detected occurrence of the condition category indicating an area human or pet occupancy.

16 . A method for controlling an environmental data monitoring and reporting system, comprising:
detecting sound in an area and generating an audio signal based on the detected sound; converting the audio signal into low-resolution audio signal data and analyzing the audio signal data, at a device processor level, to identify the detected sound as an area human or pet occupancy-related sound and provide a communication regarding the detected occupancy-related sound; and sending the communication regarding the detected occupancy-related sound,

Assignees

• Google Inc

Inventors

• Nongpiur Rajeev Conrad
• Dixon Michael

Classifications

• G08B13/1672

  using sonic detecting means, e.g. a microphone operating in the audio frequency range · CPC title

• G10L25/51 Primary

  for comparison or discrimination · CPC title

• G10L25/18

  the extracted parameters being spectral information of each sub-band · CPC title

• G08B21/0219

  Circuit arrangements · CPC title

• G06K9/00369 Primary

  Physics · mapped topic