Hearing system and method for deriving information on an acoustic scene

• US 20070269064A1
• Filed: 07/21/2006
• Published: 11/22/2007
• Est. Priority Date: 05/16/2006
• Status: Active Grant

• Current Assignee: Sonova AG (Sonova Holding AG)
• Original Assignee: Phonak AG (Sonova Holding AG)
• Inventors: Meier, Hilmar, Roeck, Hans-Ueli, Bachler, Herbert, Allegro-Baumann, Silvia, Launer, Stefan
• Granted Patent: US 8,249,284 B2
• Time in Patent Office: Days
• US Class Current: 381/313
• CPC Class Codes: H04R 25/407 Circuits for combining signals of a plurality of transducers
• CPC Class Codes: H04S 3/008 in which the audio signals are in digital form, i.e. employing more than two discrete digital channels data reduction aspects thereof based on psychoacoustics G10L19/02

Abstract

The invention relates to a method for operating a hearing system comprising an input unit, an output unit and a transmission unit operationally interconnecting said input output units. Said transmission unit implements a transfer function describing, how audio signals generated by said input unit are processed in order to derive audio signals fed to said output unit, and can be adjusted by one or more transfer function parameters. Said method comprises obtaining, by means of said input unit and with a first directional characteristic, first audio signals from incoming acoustic sound; deriving from said first audio signals a first set of sound-characterizing data; and deriving, in dependence of

• • first directional information, which is data comprising information on said first directional characteristic, and of
  • said first set of sound-characterizing data,
    a value for each of said one or more transfer function parameters. This allows to gain insight into the acoustic environment and allows for better automatic adjustments of said transfer function.

Claims

1. Method for operating a hearing system comprising an input unit, an output unit and a transmission unit operationally interconnecting said input unit and said output unit, said transmission unit implementing a transfer function which describes, how audio signals generated by said input unit are processed in order to derive audio signals fed to said output unit, and which can be adjusted by one or more transfer function parameters, said method comprising the steps of

a1) obtaining, by means of said input unit and with a first directional characteristic of said input unit, first audio signals from incoming acoustic sound;

b1) deriving from said first audio signals a first set of sound-characterizing data;

c) deriving, in dependence of

first directional information, which is data comprising information on said first directional characteristic, and of

said first set of sound-characterizing data,

a value for each of at least one of said transfer function parameters.

2. Method according to claim 1, wherein said input unit comprises a first input transducer, a second input transducer and at least a first beam former unit, the method furthermore comprising the steps of

d1) feeding first raw audio signals derived from said first input transducer to said at least one beam former unit;

d2) feeding second raw audio signals derived from said second input transducer to said at least one beam former unit;

e1) processing said first and second raw audio signals in said at least one beam former unit, such as to set said first directional characteristic and to derive said first audio signals.

3. Method according to claim 2, wherein said input unit furthermore comprises at least a first localizer unit, the method furthermore comprising the steps of

f1) feeding said first raw audio signals to said at least one first localizer unit;

f2) feeding said second raw audio signals to said at least one first localizer unit;

g1) processing said first and second raw audio signals in said at least one localizer unit, such as to derive data, referred to as localizing data, which are comprised in said first directional information;

h1) controlling said at least one first beam former unit in dependence of said localizing data.

4. Method according to claim 1, wherein step b1) comprises the steps of

i1) extracting a first set of features from said first audio signals;

and

j1) classifying said first set of features according to a set of classes, the result of said classification being comprised in said first set of sound-characterizing data.

5. Method according to claim 4, wherein said first audio signals are derived from a current acoustic scene, and wherein said result of said classification comprises, for at least one of said classes, in particular for at least two of said classes, data indicative of the similarity of said current acoustic scene and an acoustic scene of which the respective class is representative.

6. Method according to claim 1, furthermore comprising the steps of

a2) obtaining, by means of said input unit and with a second directional characteristic of said input unit, which is different from said first directional characteristic, second audio signals from incoming acoustic sound;

b2) deriving from said second audio signals a second set of sound-characterizing data; and

wherein step c) is replaced by

c′

) deriving a value for each of at least one of said transfer function parameters in dependence of

said first directional information,

said first set of sound-characterizing data,

said second set of sound-characterizing data, and of

second directional information, which is data comprising information on said second directional characteristic.

7. Method according to claim 6, wherein steps a1) and a2) take place simultaneously or successively, and steps b2) and b2) take place simultaneously or successively.

8. Method according to claim 6, wherein said hearing system comprises a first and a second hearing device, which are operationally connected to each other and which are to be worn in or near the left and the right ear, respectively, of a user of the hearing system, both hearing devices comprising at least one input transducer each, and wherein said first and/or said second directional information comprises information derived from a head-related transfer function.

9. Method according to claim 7, wherein said hearing system comprises a first and a second hearing device, which are operationally connected to each other and which are to be worn in or near the left and the right ear, respectively, of a user of the hearing system, both hearing devices comprising at least one input transducer each, and wherein said first and/or said second directional information comprises information derived from a head-related transfer function.

10. Method according to claim 1, wherein said derived value or values constitute a set of values indicative of an acoustic scene.

11. Hearing system comprising

an input unit for obtaining, with a first directional characteristic of said input unit, incoming acoustic sound and deriving therefrom first audio signals;

an output unit for receiving output audio signals and transducing these into signals to be perceived by a user of the hearing system;

a transmission unit, which is operationally interconnecting said input unit and said output unit, and which implements a transfer function, which can be adjusted by one or more transfer function parameters and which describes, how audio signals generated by said input unit are processed in order to derive said output audio signals;

a characterizing unit for deriving from said first audio signals a first set of sound-characterizing data;

an evaluating unit for deriving, in dependence of said first set of sound-characterizing data and of first directional information, which is data comprising information on said first directional characteristic, a value for each of at least one of said transfer function parameters.

12. Hearing system according to claim 11, furthermore comprising a storage unit containing data derived from a head-related transfer function and/or data related to a directional characteristic of at least one first input transducer of said input unit, and wherein said first directional information is at least in part derived from said storage unit.

13. Hearing system according to claim 11, wherein said input unit comprises at least one first input transducer, at least one second input transducer and at least one beam former unit, which is operationally connected to said first and second input transducers, and a beam former controller for controlling said at least one beam former unit, wherein said first directional information is at least in part derived from said beam former controller.

14. Hearing system according to claim 13, wherein said input unit comprises at least one localizer operationally connected to said first and second input transducers, for determining the location of sources of sound and for providing said at least one beam former controller with data related to said location of sources of sound.

15. Hearing system according to claim 11, wherein said characterizing unit comprises at least one feature extractor for extracting a first set of features from said first audio signals and at least one classifier for classifying said first set of features according to a set of classes, the result of said classification being comprised in said first set of sound-characterizing data.

16. Hearing system according to claim 11, which is a hearing-aid system comprising at least one hearing-aid device.

17. Method for deriving information on an acoustic scene, comprising the steps of

p1) obtaining, with a first directional characteristic, first audio signals from incoming acoustic sound from said acoustic scene;

p2) obtaining, with a second directional characteristic, which is different from said first directional characteristic, second audio signals from incoming acoustic sound from said acoustic scene;

q1) deriving from said first audio signals a first set of sound-characterizing data;

q2) deriving from said second audio signals a second set of sound-characterizing data;

r) deriving said information on said acoustic scene in dependence of

first directional information, which is data comprising information on said first directional characteristic,

said first set of sound-characterizing data,

second directional information, which is data comprising information on said second directional characteristic, and of

said second set of sound-characterizing data.

18. Use of the method according to claim 17 in a hearing system.

19. Method for manufacturing signals to be perceived by a user of a hearing system comprising an input unit, an output unit and a transmission unit operationally interconnecting said input unit and said output unit, said transmission unit implementing a transfer function which describes, how audio signals generated by said input unit are processed in order to derive audio signals fed to said output unit, and which can be adjusted by one or more transfer function parameters, said method comprising the steps of

s) obtaining, by means of said input unit and with a first directional characteristic of said input unit, first audio signals from incoming acoustic sound;

t) deriving from said first audio signals a first set of sound-characterizing data;

u) deriving, in dependence of

first directional information, which is data comprising information on said first directional characteristic, and of

said first set of sound-characterizing data,

a value for each of at least one of said transfer function parameters;

v) obtaining output audio signals by processing audio signals generated by said input unit according to said transfer function using said derived value or values;

w) transducing said output audio signals into said signals to be perceived by a user of the hearing system.