Room volume and room dimension estimation

• US 7,688,678 B2
• Filed: 10/26/2005
• Issued: 03/30/2010
• Est. Priority Date: 04/28/2003
• Status: Active Grant

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Jones, Douglas L., Larsen, Erik, Feng, Albert
• Primary Examiner(s): PIHULIC, DANIEL T
• Application Number:
  US11/259,619
• Publication Number:
  US 20060126858A1
• Time in Patent Office: 1,616 Days
• Field of Search: 367/99, 367/118, 367/127, 702/156, 702/155, 702/171
• US Class Current: 367/99
• CPC Class Codes: G01H 3/00 Measuring characteristics of vibrations by using a detector in a fluid G01H7/00, G01H9/00, G01H11/00 take precedence
• CPC Class Codes: G01H 7/00 Measuring reverberation time ; room acoustic measurements
• CPC Class Codes: H04R 2225/41 Detection or adaptation of hearing aid parameters or programs to listening situation, e.g. pub, forest
• CPC Class Codes: H04S 7/307 Frequency adjustment, e.g. tone control H04S7/301 takes precedence

Abstract

One embodiment of the invention includes a processing subsystem (30) responsive to the detection of sound coming from a room (26) to establish an acoustic impulse response for the room (26), and determine a number of sound reflections corresponding to the impulse response. This subsystem (30) is further operable to determine volume of the room (26), one or more dimensions of the room (26) and/or at least one absorption coefficient of a room boundary as a function of the sound reflections.

Claims

1. A method, comprising:

detecting sound coming from a room;

establishing an acoustic impulse response of the room;

determining a number of sound reflections corresponding to the impulse response; and

determining volume of the room as a function of the sound reflections.

2. The method of claim 1, which includes determining at least one value corresponding to a dimension of the room from the volume.

3. The method of claim 1, which includes determining at least one value corresponding to an absorption coefficient at a boundary of the room from the volume.

4. A method, comprising:

detecting sound reflected from one or more surfaces of a room;

counting a number of sound reflections from the one or more surfaces over a selected time interval; and

estimating volume of the room as a function of the number of sound reflections and the time interval.

5. The method of claim 4, which includes generating an impulsive sound to cause the sound reflected from the one or more surfaces.

6. The method of claim 4, which includes determining at least one of a dimension of the room and an acoustic absorption coefficient of a boundary of the room.

7. The method of claim 4, wherein the function corresponds to V=(4π

/3N)(cT)³ with V representing the volume of the room, N representing the number of the sound reflections, c representing sound propagation velocity, and T representing the selected time interval.

8. The method of claim 4, wherein:

said detecting is performed with at least one microphone; and

said counting and said estimating are performed with one or more processors.

9. The method of claim 8, wherein said microphone and said one or more processors are included in a hearing assistance device.

10. A method, comprising:

detecting a number of sound reflections of a room in response to an impulsive sound;

determining one or more values corresponding to reverberation time from the number of sound reflections based on a mirror image reflection model; and

estimating at least one of a dimension of the room and an acoustic absorption coefficient of a boundary of the room as a function of the one or more values.

11. The method of claim 10, wherein said determining includes estimating volume of the room and determining the one or more values from the volume of the room.

12. The method of claim 10, wherein said determining includes calculating delay and amplitude of the number of reflections.

13. The method of claim 10, wherein said determining includes performing an annealing routine.

14. The method of claim 10, which includes generating the impulsive sound.

15. An apparatus, comprising:

a device carrying logic executable by one or more processors to process data corresponding to a number of sound reflections coming from a room over an selected time interval in response to an impulsive sound, the logic being operable to provide an estimate of volume of the room as a function of the number of sound reflections and the selected time interval.

16. The apparatus of claim 15, wherein the logic includes a number of software instructions and the device includes a computer-readable memory storing the software instructions.

17. The apparatus of claim 16, wherein the computer-readable memory is of a removable memory device type.

18. The apparatus of claim 15, wherein the logic operates with the function corresponding to V=(4π

/3N)(cT)₃;

with V representing the volume of the room, N representing the number of the sound reflections, c representing sound propagation velocity, and T representing the selected time interval.

19. The apparatus of claim 15, wherein the logic further operates to estimate at least one of a dimension of the room and an acoustic absorption coefficient of a boundary of the room.

20. The apparatus of claim 15, wherein the volume is determined with a mirror image reflection model of an impulse response of the room.

21. A system, comprising:

a sensor for detecting sound; and

a processing subsystem operable to receive sound-representative signals from the sensor to determine volume of a room as a function of a number of sound reflections of the room in response to an impulsive sound based on a mirror image reflection model of an impulse response of the room.

22. The system of claim 21, wherein the function corresponds to V=(4π

/3N)(cT)³;

with V representing the volume of the room, N representing the number of the sound reflections, c representing sound propagation velocity, and T representing the selected time interval.

23. The system of claim 21, wherein the processing subsystem includes means for estimating at least one of a dimension of the room and an acoustic absorption parameter of a boundary of the room.

24. The system of claim 21, further comprising an output device selectively responsive to the volume of the room.

25. The system of claim 21, wherein the processing subsystem includes means for recording the sound-representative signals.