NOISE REDUCING DEVICE, NOISE REDUCING METHOD, NOISE REDUCING PROGRAM, AND NOISE REDUCING AUDIO OUTPUTTING DEVICE

• US 20080112569A1
• Filed: 10/01/2007
• Published: 05/15/2008
• Est. Priority Date: 11/14/2006
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: ASADA, Kohei
• Granted Patent: US 9,741,332 B2
• Time in Patent Office: Days
• US Class Current: 381/71.1
• CPC Class Codes: G10K 11/17823 Reference signals, e.g. ambient acoustic environment
• CPC Class Codes: G10K 11/17825 Error signals
• CPC Class Codes: G10K 11/1783 handling or detecting of non-standard events or conditions, e.g. changing operating modes under specific operating conditions
• CPC Class Codes: G10K 11/17833 by using a self-diagnostic function or a malfunction prevention function, e.g. detecting abnormal output levels
• CPC Class Codes: G10K 11/17873 using a reference signal without an error signal, e.g. pure feedforward
• CPC Class Codes: G10K 11/17875 using an error signal without a reference signal, e.g. pure feedback
• CPC Class Codes: G10K 11/17879 using both a reference signal and an error signal
• CPC Class Codes: G10K 11/17881 the reference signal being an acoustic signal, e.g. recorded with a microphone
• CPC Class Codes: G10K 11/17885 additionally using a desired external signal, e.g. pass-through audio such as music or speech
• CPC Class Codes: G10K 2210/1081 Earphones, e.g. for telephones, ear protectors or headsets
• CPC Class Codes: G10K 2210/3013 Analogue, i.e. using analogue computers or circuits
• CPC Class Codes: G10K 2210/3033 Information contained in memory, e.g. stored signals or transfer functions
• CPC Class Codes: G10K 2210/30391 Resetting of the filter parameters or changing the algorithm according to prevailing conditions
• CPC Class Codes: G10K 2210/3042 Parallel processing
• CPC Class Codes: G10K 2210/3222 Manual tuning
• CPC Class Codes: G10K 2210/509 Hybrid, i.e. combining different technologies, e.g. passive and active
• CPC Class Codes: H04R 1/1083 Reduction of ambient noise active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06
• CPC Class Codes: H04R 2460/01 Hearing devices using active noise cancellation

Abstract

A noise reducing device includes: an acoustic-to-electric conversion section for collecting noise and outputting an analog noise signal; an analog-to-digital conversion section for converting the analog noise signal into a digital noise signal; and a digital processing section for generating a digital noise reducing signal on a basis of the digital noise signal and a desired parameter. The device further includes: a retaining section for retaining a plurality of parameters corresponding to a plurality of kinds of noise characteristics; a setting section for setting one of the plurality of parameters as the desired parameter of the digital processing section; a digital-to-analog conversion section for converting the digital noise reducing signal into an analog noise reducing signal; and an electric-to-acoustic conversion section for outputting noise reducing sound on a basis of the analog noise reducing signal.

Claims

1. A noise reducing device comprising:

an acoustic-to-electric conversion section for collecting noise and outputting an analog noise signal;

an analog-to-digital conversion section for converting said analog noise signal into a digital noise signal;

a digital processing section for generating a digital noise reducing signal on a basis of said digital noise signal and a desired parameter;

a retaining section for retaining a plurality of said parameters corresponding to a plurality of kinds of noise characteristics;

a setting section for setting one of said plurality of parameters as said desired parameter of said digital processing section;

a digital-to-analog conversion section for converting said digital noise reducing signal into an analog noise reducing signal; and

an electric-to-acoustic conversion section for outputting noise reducing sound on a basis of said analog noise reducing signal.

2. The noise reducing device according to claim 1,

wherein said setting section sequentially selects a parameter to be supplied to said digital processing section from said plurality of said parameters on a basis of an operation input.

3. The noise reducing device according to claim 1, further comprising

a noise characteristic analyzing section for analyzing a characteristic of the noise collected by said acoustic-to-electric conversion section,

wherein said setting section sets one of said plurality of parameters as said desired parameter on a basis of a result of analysis of said noise characteristic analyzing section.

4. The noise reducing device according to claim 1, further comprising

an evaluating section for evaluating an effect of reducing said noise when each of said plurality of parameters is used,

wherein said setting section sets one of said plurality of parameters as said desired parameter on a basis of a result of evaluation of said evaluating section.

5. The noise reducing device according to claim 3,

wherein at least one of a time of power being turned on, a time of a predetermined operation input being given, and a time after passage of each fixed interval,

said noise characteristic analyzing section analyzes the characteristic of said noise, and

said setting section sets one of said plurality of parameters as said desired parameter on a basis of a result of analysis of said noise characteristic analyzing section.

6. The noise reducing device according to claim 3,

wherein said electric-to-acoustic conversion section outputs sound on a basis of said analog noise reducing signal and a predetermined audio signal,

said noise characteristic analyzing section analyzes the characteristic of said noise when said predetermined audio signal represents a silence, and

said setting section sets one of said plurality of parameters as said desired parameter on a basis of a result of analysis of said noise characteristic analyzing section.

7. The noise reducing device according to claim 3,

wherein when change in the noise collected by said acoustic-to-electric conversion section is equal to or more than a predetermined magnitude,

said noise characteristic analyzing section analyzes the characteristic of said noise, and

said setting section sets one of said plurality of parameters as said desired parameter on a basis of a result of analysis of said noise characteristic analyzing section.

8. The noise reducing device according to claim 4,

wherein at least one of a time of power being turned on, a time of a predetermined operation input being given, and a time after passage of each fixed interval,

said evaluating section evaluates the effect of reducing said noise, and

said setting section sets one of said plurality of parameters as said desired parameter on a basis of a result of evaluation of said evaluating section.

9. The noise reducing device according to claim 4,

wherein said electric-to-acoustic conversion section outputs sound on a basis of said analog noise reducing signal and a predetermined audio signal,

said evaluating section evaluates the effect of reducing said noise when said predetermined audio signal represents a silence, and

said setting section sets one of said plurality of parameters as said desired parameter on a basis of a result of evaluation of said evaluating section.

10. The noise reducing device according to claim 4,

wherein when change in the noise collected by said acoustic-to-electric conversion section is equal to or more than a predetermined magnitude,

said evaluating section evaluates said noise, and

said setting section sets one of said plurality of parameters as said desired parameter on a basis of a result of evaluation of said evaluating section.

11. The noise reducing device according to claim 3,

wherein said electric-to-acoustic conversion section outputs sound on a basis of said analog noise reducing signal and a predetermined audio signal, and

at least one of a time of power being turned on, a time of a predetermined operation input being given, and a time after passage of each fixed interval, and at a time when said predetermined audio signal represents a silence,

said noise characteristic analyzing section analyzes the characteristic of said noise, and

said setting section sets one of said plurality of parameters as said desired parameter on a basis of a result of analysis of said noise characteristic analyzing section.

12. The noise reducing device according to claim 4,

wherein said electric-to-acoustic conversion section outputs sound on a basis of said analog noise reducing signal and a predetermined audio signal, and

at least one of a time of power being turned on, a time of a predetermined operation input being given, and a time after passage of each fixed interval, and at a time when said predetermined audio signal represents a silence,

said evaluating section evaluates the effect of reducing said noise, and

said setting section sets one of said plurality of parameters as said desired parameter on a basis of a result of evaluation of said evaluating section.

13. The noise reducing device according to claim 3,

wherein said acoustic-to-electric conversion section collects synthetic sound at a position of synthesis of said noise and said noise reducing sound, and

when said noise characteristic analyzing section analyzes the characteristic of said noise, said electric-to-acoustic conversion section stops outputting said noise reducing sound on the basis of said analog noise reducing signal.

14. The noise reducing device according to claim 1, further comprising

an analog processing section for generating another analog noise reducing signal on a basis of said analog noise signal,

wherein said electric-to-acoustic conversion section outputs the noise reducing sound on a basis of said analog noise reducing signal and said other analog noise reducing signal.

15. The noise reducing device according to claim 1,

wherein said acoustic-to-electric conversion section includes a first acoustic-to-electric conversion section for collecting synthetic sound of said noise and said noise reducing sound, and a second acoustic-to-electric conversion section for collecting said noise, said second acoustic-to-electric conversion section being disposed at a different position from said first acoustic-to-electric conversion section,

said digital processing section generates a first digital noise reducing signal on a basis of a first digital noise signal obtained by digitizing a first analog noise signal output by said first acoustic-to-electric conversion section and a first parameter used to generate said first digital noise reducing signal, and generates a second digital noise reducing signal on a basis of a second digital noise signal obtained by digitizing a second analog noise signal output by said second acoustic-to-electric conversion section and a second parameter used to generate said second digital noise reducing signal,

said retaining section retains a plurality of said first parameters and a plurality of said second parameters corresponding to characteristics of said noise,

said digital-to-analog conversion section converts a synthetic digital noise reducing signal obtained by synthesizing said first digital noise reducing signal and said second digital noise reducing signal into a synthetic analog noise reducing signal, and

said electric-to-acoustic conversion section outputs said noise reducing sound on a basis of said synthetic analog noise reducing signal.

16. A noise reducing method comprising:

an outputting step of an acoustic-to-electric conversion section collecting noise and outputting an analog noise signal;

an analog-to-digital conversion step of converting said analog noise signal into a digital noise signal;

a digital processing step of generating a digital noise reducing signal on a basis of said digital noise signal and a desired parameter among a plurality of said parameters corresponding to a plurality of kinds of noise characteristics, the plurality of said parameters being retained by a retaining section;

a setting step of setting one of said plurality of parameters as said desired parameter;

a digital-to-analog conversion step of converting said digital noise reducing signal into an analog noise reducing signal; and

an outputting step of an electric-to-acoustic conversion section outputting noise reducing sound on a basis of said analog noise reducing signal.

17. A computer readable recording medium on which a program is recorded, said program making a computer perform:

an outputting step of an acoustic-to-electric conversion section collecting noise and outputting an analog noise signal;

an analog-to-digital conversion step of converting said analog noise signal into a digital noise signal;

a digital processing step of generating a digital noise reducing signal on a basis of said digital noise signal and a desired parameter among a plurality of said parameters corresponding to a plurality of kinds of noise characteristics, the plurality of said parameters being retained by a retaining section;

a setting step of setting one of said plurality of parameters as said desired parameter;

a digital-to-analog conversion step of converting said digital noise reducing signal into an analog noise reducing signal; and

an outputting step of an electric-to-acoustic conversion section outputting noise reducing sound on a basis of said analog noise reducing signal.