Sound processing apparatus and sound processing method

Patent metadata

Field	Value
Publication number	US-10139470-B2
Application number	US-201514604038-A
Country	US
Kind code	B2
Filing date	Jan 23, 2015
Priority date	Feb 13, 2014
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

A sound processing apparatus includes a sound collection position calculating unit configured to calculate sound collection positions of sound signals of multiple channels on the basis of the sound signals, a sound source direction calculating unit configured to calculate a sound source direction on the basis of the sound signals of multiple channels, a first transfer function calculating unit configured to calculate a first transfer function corresponding to the sound source direction on the basis of the sound signals of multiple channels, and a second transfer function calculating unit configured to calculate a second transfer function by interpolating the first transfer function corresponding to each of a plurality of sound source directions.

First claim

What is claimed is:

1. A sound processing apparatus comprising:
a sound collection position calculating unit configured to calculate sound collection positions of sound signals of multiple channels on the basis of the sound signals;
a sound source direction calculating unit configured to calculate sound source directions respectively corresponding to the multiple channels on the basis of the sound signals of the multiple channels;
a first transfer function calculating unit configured to calculate first transfer functions respectively corresponding to the sound source directions on the basis of the sound signals of the multiple channels; and
a second transfer function calculating unit configured to calculate a second transfer function by interpolating the first transfer functions between the sound source directions.

2. The sound processing apparatus according to claim 1 , further comprising a time difference calculating unit configured to calculate an inter-channel time difference of the sound signals,
wherein the sound collection position calculating unit includes
a first state predicting unit configured to predict current sound source state information from previous sound source state information as sound source state information including the sound collection position, and
a first state updating unit configured to update the current sound source state information so as to reduce a difference between the time difference calculated by the time difference calculating unit and a time difference based on the current sound source state information.

3. The sound processing apparatus according to claim 2 , wherein the time difference calculating unit calculates the inter-channel time difference of the sound signals in which the sound collection positions are located within a predetermined range.

4. The sound processing apparatus according to claim 2 , wherein time difference information at a timing which is delayed by at least a predetermined delay time from the time difference information input to the sound collection position calculating unit is input to the sound source direction calculating unit, and
wherein time difference information at a timing which is delayed by at least the predetermined delay time from the sound signal associated with the time difference information input to the sound collection position calculating unit is input to the first transfer function calculating unit.

5. The sound processing apparatus according to claim 2 , wherein the sound source direction calculating unit includes
a second state predicting unit configured to predict current sound source state information from previous sound source state information as sound source state information including the sound source position, and
a second state updating unit configured to update the current sound source state information so as to reduce a difference between the time difference calculated by the time difference calculating unit and a time difference based on the current sound source state information.

6. The sound processing apparatus according to claim 5 , wherein the second transfer function calculating unit interpolates the first transfer function calculated by the first transfer function calculating unit by weighting based on an amount of sound source state information updated by the second state updating unit.

7. The sound processing apparatus according to claim 5 , further comprising a second sound source direction calculating unit configured to calculate a sound source direction on the basis of the second transfer function calculated by the second transfer function calculating unit and the sound signals of multiple channels,
wherein the second state updating unit updates the current sound source state information so as to reduce a difference between the sound source direction calculated by the second sound source direction calculating unit and a sound source direction based on the current sound source state information.

8. The sound processing apparatus according to claim 1 , wherein the sound source direction calculating unit includes
a third transfer function calculating unit configured to calculate a third transfer function indicating a phase variation due to propagation of sound to the sound collection position calculated by the sound collection position calculating unit for each sound source direction, and
a first sound source direction determining unit configured to determine the sound source direction on the basis of the third transfer function calculated by the third transfer function calculating unit and the sound signals of multiple channels.

9. A sound processing method in a sound processing apparatus, comprising:
a step of calculating sound collection positions of sound signals of multiple channels on the basis of the sound signals;
a step of calculating sound source directions respectively corresponding to the multiple channels on the basis of the sound signals of the multiple channels;
a step of calculating first transfer functions respectively corresponding to the sound source directions on the basis of the sound signals of the multiple channels; and
a step of calculating a second transfer function by interpolating the first transfer functions between the sound source directions.

10. The sound processing apparatus according to claim 1 , wherein the second transfer function is configured to calculate the second transfer function corresponding to a target sound source direction by
specifying neighboring sound source directions among the sound source directions interposing the target sound source direction therebetween, as a first reference sound source and a second reference sound source, and
interpolating the first transfer function corresponding to the first reference sound source and the first transfer function corresponding to the second reference sound source.

Assignees

• Honda Motor Co Ltd

Inventors

• Nakamura Keisuke
• Nakadai Kazuhiro
• Ambrose Surya

Classifications

• G01S3/8006 Primary

  Multi-channel systems specially adapted for direction-finding, i.e. having a single aerial system capable of giving simultaneous indications of the directions of different signals · CPC title

• G01S3/808

  using transducers spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems · CPC title

• G01S5/20

  Position of source determined by a plurality of spaced direction-finders · CPC title

• G01S3/801

  Details {(G01S3/82, G01S3/84, G01S3/86 take precedence)} · CPC title