Sound processing device and non-transitory computer-readable storage medium

• US 10,276,182 B2
• Filed: 08/02/2017
• Issued: 04/30/2019
• Est. Priority Date: 08/30/2016
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Otani, Takeshi, Togawa, Taro, Nakayama, Sayuri
• Primary Examiner(s): Azad, Abul K
• Application Number:
  US15/666,722
• Publication Number:
  US 20180061434A1
• Time in Patent Office: 636 Days
• CPC Class Codes: G10K 11/178 by electro-acoustically regenerating the original acoustic waves in anti-phase
• CPC Class Codes: G10K 2210/30232 Transfer functions, e.g. impulse response
• CPC Class Codes: G10K 2210/3045 Multiple acoustic inputs, single acoustic output
• CPC Class Codes: G10L 2021/02087 the noise being separate speech, e.g. cocktail party
• CPC Class Codes: G10L 2021/02161 Number of inputs available containing the signal or the noise to be suppressed
• CPC Class Codes: G10L 21/0208 Noise filtering
• CPC Class Codes: G10L 21/0232 Processing in the frequency domain
• CPC Class Codes: G10L 21/0272 Voice signal separating
• CPC Class Codes: G10L 21/0316 by changing the amplitude
• CPC Class Codes: H03G 3/32 the control being dependent upon ambient noise level or sound level
• CPC Class Codes: H03G 5/165 Equalizers; Volume or gain control in limited frequency bands
• CPC Class Codes: H04R 2430/03 Synergistic effects of band splitting and sub-band processing
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407

Abstract

A sound processing device includes a processor configured to generate a first frequency spectrum of a first sound signal corresponding to a first sound received at a first input device and a second frequency spectrum of a second sound signal corresponding to the first sound received at a second input device, calculate a transfer characteristic based on a first difference between an intensity of the first frequency spectrum and an intensity of the second frequency spectrum, generate a third frequency spectrum of a third sound signal transmitted from the first input device and a fourth frequency spectrum of a fourth sound signal transmitted from the second input device, specify a suppression level of an intensity of the fourth frequency spectrum based on a second difference between an intensity of the third frequency spectrum and an intensity of the fourth frequency spectrum.

Claims

1. A sound processing device configured to be coupled to a first input device and a second input device, the sound processing device comprising:

a memory; and

a processor coupled to the memory and configured to

generate a first frequency spectrum of a first sound signal corresponding to a first sound received at the first input device and a second frequency spectrum of a second sound signal corresponding to the first sound received at the second input device,

calculate a transfer characteristic based on a first difference between an intensity of the first frequency spectrum and an intensity of the second frequency spectrum,

generate a third frequency spectrum of a third sound signal transmitted from the first input device and a fourth frequency spectrum of a fourth sound signal transmitted from the second input device,

specify a suppression level of an intensity of the fourth frequency spectrum based on a second difference between an intensity of the third frequency spectrum and an intensity of the fourth frequency spectrum, and the transfer characteristic, and

suppress the intensity of the fourth frequency spectrum using the specified suppression level.

2. The sound processing device according to claim 1, wherein the processor is configured to

specify the suppression level of the intensity of the fourth frequency spectrum based on a third difference between the first difference and the second difference.

3. The sound processing device according to claim 2, wherein the processor is configured to

specify the suppression level so that the suppression level increases when the third difference increases.

4. The sound processing device according to claim 2, wherein the processor is configured to

specify the suppression level so that the suppression level is reduced when the third difference is reduced.

5. The sound processing device according to claim 1, wherein the processor is configured to

smooth the suppression levels in bands of a plurality of frequencies of the fourth frequency spectrum.

6. The sound processing device according to claim 1, wherein the processor is configured to

smooth the suppression levels in a plurality of frames of the fourth sound signal.

7. The sound processing device according to claim 5, wherein the processor is configured to

suppress the intensity of the fourth frequency spectrum based on the smoothed suppression level.

8. The sound processing device according to claim 6, wherein the processor is configured to

suppress the intensity of the fourth frequency spectrum based on the smoothed suppression level.

9. A sound processing device configured to be coupled to a first input device, a second input device, and a third input device, the sound processing device comprising:

a memory; and

a processor coupled to the memory and configured to,

generate a first frequency spectrum of a first sound signal corresponding to a first sound received at the first input device, a second frequency spectrum of a second sound signal corresponding to the first sound received at the second input device, and a third frequency spectrum of a third sound signal corresponding to the first sound received at the third input device,

calculate transfer characteristics based on mutual differences between an intensity of the first frequency spectrum, an intensity of the second frequency spectrum, and an intensity of the third frequency spectrum,

specify a first suppression level, a second suppression level, and a third suppression level respectively applied to a fourth frequency spectrum of a fourth sound signal transmitted from the first input device, a fifth frequency spectrum of a fifth sound signal transmitted from the second input device, and a sixth frequency spectrum of a sixth sound signal transmitted from the third input device based on an intensity of the fourth frequency spectrum, an intensity of the fifth frequency spectrum, an intensity of the sixth frequency spectrum, and the transfer characteristics,

suppress the intensity of the fourth frequency spectrum using the first suppression level, suppress the intensity of the fifth frequency spectrum using the second suppression level, and suppress the intensity of the sixth frequency spectrum using the third suppression level.

10. A non-transitory computer-readable storage medium storing a program that causes an information processing apparatus to execute a process, the information processing apparatus being configured to be coupled to a first input device and a second input device, the process comprising:

generating a first frequency spectrum of a first sound signal corresponding to a first sound received at the first input device and a second frequency spectrum of a second sound signal corresponding to the first sound received at the second input device;

calculating a transfer characteristic based on a first difference between an intensity of the first frequency spectrum and an intensity of the second frequency spectrum;

generating a third frequency spectrum of a third sound signal transmitted from the first input device and a fourth frequency spectrum of a fourth sound signal transmitted from the second input device;

specifying a suppression level of an intensity of the fourth frequency spectrum based on a second difference between an intensity of the third frequency spectrum and an intensity of the fourth frequency spectrum, and the transfer characteristic; and

suppressing the intensity of the fourth frequency spectrum using the specified suppression level.

11. The non-transitory computer-readable storage medium according to claim 10, wherein

in the specifying, the suppression level of the intensity of the fourth frequency spectrum is specified based on a third difference between the first difference and the second difference.

12. The non-transitory computer-readable storage medium according to claim 11, wherein

in the specifying, the suppression level is specified so that the suppression level increases when the third difference increases.

13. The non-transitory computer-readable storage medium according to claim 11, wherein

in the specifying, the suppression level is specified so that the suppression level is reduced when the third difference is reduced.

14. The non-transitory computer-readable storage medium according to claim 10, the process further comprising:

smoothing the suppression levels in bands of a plurality of frequencies of the fourth frequency spectrum.

15. The non-transitory computer-readable storage medium according to claim 10, the process further comprising:

smoothing the suppression levels in a plurality of frames of the fourth sound signal.

16. The non-transitory computer-readable storage medium according to claim 14, wherein

in the suppressing, the intensity of the fourth frequency spectrum is suppressed based on the smoothed suppression level.

17. The non-transitory computer-readable storage medium according to claim 15, wherein

in the suppressing, the intensity of the fourth frequency spectrum is suppressed based on the smoothed suppression level.