JPH0629764A - Wind noise reduction microphone amplifier - Google Patents
Wind noise reduction microphone amplifierInfo
- Publication number
- JPH0629764A JPH0629764A JP20130091A JP20130091A JPH0629764A JP H0629764 A JPH0629764 A JP H0629764A JP 20130091 A JP20130091 A JP 20130091A JP 20130091 A JP20130091 A JP 20130091A JP H0629764 A JPH0629764 A JP H0629764A
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- Prior art keywords
- wind noise
- noise
- attenuator
- wind
- band
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- Tone Control, Compression And Expansion, Limiting Amplitude (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はマイクロフォン増幅装置
に関し、特に風雑音（風吹かれノイズ）のあるときのみ
風雑音を低減するマイクロフォン増幅器に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microphone amplifier, and more particularly to a microphone amplifier which reduces wind noise only when there is wind noise.
【０００２】[0002]
【従来の技術】従来のマイクロフォン増幅器は図１１に
示すように、マイクロフォン１の信号を入力としてロー
カットフィルター１５との整合をとるための前置増幅器
２と、風雑音（風吹かれノイズ）の成分（２０〜約１５
０Ｈｚ）をカットするローカットフィルター１５と、ロ
ーカットフィルター入り（ポジションＰ2）と無（ポジ
ションＰ1：フラット特性）の切り換えスイッチ１４
と、フィルター１５の出力との整合及び次装置への整合
と出力レベルを得るための緩衝増幅器１５を有してい
る。2. Description of the Related Art As shown in FIG. 11, a conventional microphone amplifier receives a signal from a microphone 1 as a preamplifier 2 for matching with a low-cut filter 15 and a wind noise component (wind noise). 20 to about 15
0Hz) low cut filter 15 and switch 14 with low cut filter (position P 2 ) and no (position P 1 : flat characteristic)
And a buffer amplifier 15 for obtaining a matching with the output of the filter 15 and a matching with the next device and an output level.
【０００３】従来のマイクロフォン増幅器の風雑音（風
吹かれノイズ）に対する動作は、風雑音成分（２０Ｈｚ
〜約１５０Ｈｚ）をローカットフィルター１５で単に周
波数的にカットする。The operation of the conventional microphone amplifier against wind noise (wind blowing noise) is as follows.
(About 150 Hz) is simply cut in frequency by the low-cut filter 15.
【０００４】したがって、風がなくなったとき（風雑音
がないとき）も、切り換えスイッチ１４をポジションＰ
1：フラット特性に切り換えない限り、２０Ｈｚ〜約１
５０Ｈｚの周波数成分を欠落したまま信号を増幅する。Therefore, even when there is no wind (when there is no wind noise), the changeover switch 14 is set to the position P.
1 : 20Hz to approx. 1 unless switching to flat characteristics
The signal is amplified while the frequency component of 50 Hz is missing.
【０００５】[0005]
【発明が解決しようとする課題】従来のマイクロフォン
増幅装置では、風雑音（風吹かれノイズ）に対し風雑音
成分（２０Ｈｚ〜約１５０Ｈｚ）を単に周波数的にカッ
トするフィルターを内蔵する。The conventional microphone amplification device has a built-in filter that simply cuts the wind noise component (20 Hz to about 150 Hz) with respect to wind noise (wind blow noise) in terms of frequency.
【０００６】したがって、風が吹いていないとき（風雑
音がないとき）も、上記の周波数成分（２０Ｈｚ〜約１
５０Ｈｚ）を欠落したまま音響信号を増幅するため、マ
イクロフォンの入力信号を忠実に増幅しているとはいえ
ない問題点があった。Therefore, even when the wind is not blowing (when there is no wind noise), the above-mentioned frequency components (20 Hz to about 1).
Since the acoustic signal is amplified with the loss of 50 Hz), it cannot be said that the input signal of the microphone is faithfully amplified.
【０００７】本発明の目的は前記課題を解決した風雑音
（風吹かれノイズ）低減マイクロフォン増幅装置を提供
することにある。An object of the present invention is to provide a wind noise (wind blowing noise) reducing microphone amplifying device which solves the above problems.
【０００８】[0008]
【課題を解決するための手段】前記目的を達成するた
め、本発明に係る風雑音（風吹かれノイズ）低減マイク
ロフォン増幅装置においては、風雑音（風吹かれノイ
ズ）を含んだ音響信号を入力して次段への信号処理を行
うに足る利得を有する広帯域増幅器と、前記増幅された
音響信号を風雑音を主に含む周波数帯域と人間の音声を
主に含む周波数帯域とに分割する帯域分割器と、風雑音
を主に含む帯域の増幅器の出力信号を風雑音がある場合
に電子的に一定量減衰させる電子式アッテネータと、風
雑音検出のための全波整流器及び比較器と、「風雑音有
り」と判定した場合、前記電子式アッテネータを動作さ
せるアッテネータ制御回路とを有するものである。In order to achieve the above object, in a wind noise (wind blowing noise) reduction microphone amplifying apparatus according to the present invention, an acoustic signal including wind noise (wind blowing noise) is input. A wideband amplifier having a gain sufficient to perform signal processing to the next stage; and a band divider that divides the amplified acoustic signal into a frequency band mainly containing wind noise and a frequency band mainly containing human voice. , An electronic attenuator that electronically attenuates the output signal of the amplifier in the band mainly including wind noise by a certain amount when there is wind noise, a full-wave rectifier and a comparator for wind noise detection, And an attenuator control circuit for operating the electronic attenuator.
【０００９】また、前記電子式アッテネータに代えて、
電子的に連続減衰させる電子式ボリュームと、風雑音を
抽出し、電子式ボリュームの制御電圧を発生する全波整
流器とを有するものである。Further, in place of the electronic attenuator,
It has an electronic volume that is electronically continuously attenuated and a full-wave rectifier that extracts wind noise and generates a control voltage for the electronic volume.
【００１０】[0010]
【作用】本発明では、風雑音を含む周波数帯域と人間の
音声を主に含む周波数帯域に分割し、風雑音について一
定量減衰させるようにしたものである。According to the present invention, the frequency band including wind noise and the frequency band mainly including human voice are divided, and the wind noise is attenuated by a certain amount.
【００１１】[0011]
【実施例】以下、本発明の一実施例を図により説明す
る。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.
【００１２】（実施例１）図１は本発明の実施例を示す
システムブロックダイヤグラムである。(Embodiment 1) FIG. 1 is a system block diagram showing an embodiment of the present invention.
【００１３】図において、本実施例に係るマイクロフォ
ン増幅器は、マイクロフォン１からの風雑音（風吹かれ
ノイズ）を含んだ音響信号を入力して次段への信号処理
を行うに足る利得を有する広帯域前置増幅器２と、増幅
された音響信号を風雑音を主に含む周波数帯域と人間の
音声を主に含む周波数帯域とに分割する帯域分割器３
と、風雑音を主に含む帯域の増幅器６の出力信号を風雑
音がある場合に電子的に一定量減衰させる電子式アッテ
ネータ７と、風雑音検出のための全波整流器８と比較器
９を有し、「風雑音有」と判定した場合に、電子式アッ
テネータを動作させるアッテネータ制御回路１０とを有
している。In the figure, the microphone amplifier according to the present embodiment has a wideband front end having a gain sufficient to input an acoustic signal including wind noise (wind noise) from the microphone 1 and to perform signal processing to the next stage. An on-amplifier 2 and a band divider 3 for dividing the amplified acoustic signal into a frequency band mainly containing wind noise and a frequency band mainly containing human voice.
An electronic attenuator 7 for electronically attenuating the output signal of the amplifier 6 in a band mainly including wind noise when there is wind noise, a full-wave rectifier 8 and a comparator 9 for wind noise detection. And an attenuator control circuit 10 that operates the electronic attenuator when it is determined that “wind noise is present”.
【００１４】また５に混合器、１１は平滑時定数設定
器、１２は基準電圧発生器、１３は立上り・立下り時定
数設定器である。Reference numeral 5 is a mixer, 11 is a smoothing time constant setting device, 12 is a reference voltage generator, and 13 is a rising / falling time constant setting device.
【００１５】マイクロフォン１に風があたった場合、図
２に示すように風の音圧は周波数に対し、１／ｆの傾斜
をもっており、マイクロフォン１の出力１１には、周波
数が低下するにしたがって６ｄＢ／ｏｃｔで出力電圧は
増加する。When the microphone 1 is exposed to the wind, the sound pressure of the wind has a slope of 1 / f with respect to the frequency as shown in FIG. 2, and the output 11 of the microphone 1 has 6 dB / oct as the frequency decreases. The output voltage increases with.
【００１６】図３は広帯域前置増幅器２の周波数特性の
図である。通常、特殊な用途のマイクロフォンを除き、
最大の周波数帯域は音楽収音用の２０Ｈｚ〜２０ＫＨｚ
である。FIG. 3 is a diagram of frequency characteristics of the wideband preamplifier 2. Usually except for special purpose microphones,
The maximum frequency band is 20Hz to 20KHz for collecting music
Is.
【００１７】したがって、広帯域前置増幅器２の周波数
帯域は１Ｈｚ〜１００ＫＨｚ（−３ｄＢ帯域）に設定さ
れている。出力２２，２３は入力２１に対し利得Ａｖ1
を持つ。本例の利得Ａｖ1は約３２倍である。Therefore, the frequency band of the wideband preamplifier 2 is set to 1 Hz to 100 KHz (-3 dB band). The outputs 22 and 23 have a gain Av 1 with respect to the input 21.
have. The gain Av 1 of this example is about 32 times.
【００１８】図４は帯域分割器３の周波数特性の図であ
る。帯域分割の−６ｄＢクロスオーバー周波数は２００
Ｈｚであり、帯域分割の傾斜は６ｄＢ／ｏｃｔのスロー
プに設定されている。FIG. 4 is a diagram of frequency characteristics of the band divider 3. The band division -6 dB crossover frequency is 200
Hz, and the slope of the band division is set to a slope of 6 dB / oct.
【００１９】出力３２は入力３１に対し、周波数特性約
３００Ｈｚ〜１００ＫＨｚ（−３ｄＢ帯域）、利得１倍
（０ｄＢ）、出力３３は入力３１に対し、周波数特性１
Ｈｚ〜約１５０ＫＨｚ（−３ｄＢ帯域）、利得１倍（０
ｄＢ）である。The output 32 has a frequency characteristic of about 300 Hz to 100 KHz (-3 dB band) and a gain of 1 (0 dB) with respect to the input 31, and the output 33 has a frequency characteristic of 1 with respect to the input 31.
Hz to about 150 KHz (-3 dB band), gain 1 time (0
dB).
【００２０】２００Ｈｚ〜２０ＫＨｚ増幅器４及び２０
Ｈｚ〜２００ＫＨｚ増幅器６は周波数特性１０Ｈｚ〜４
０ＫＨｚ（−３ｄＢ帯域）、入力４１，６１に対する出
力４２，４２の利得が１０倍である。200 Hz to 20 KHz amplifiers 4 and 20
Hz-200 KHz amplifier 6 has frequency characteristics of 10 Hz-4
The gain of the outputs 42, 42 with respect to the inputs 41, 61 is 10 times, at 0 KHz (-3 dB band).
【００２１】電子式アッテネータ７はコントロール入力
７３に制御信号（図９のＶｃ以上の電圧をもつ波形信
号）のとき、出力７２は入力７２に対し−２０ｄＢ（１
／１０倍）の減衰を行う。When the electronic attenuator 7 receives a control signal (waveform signal having a voltage higher than Vc in FIG. 9) at the control input 73, the output 72 outputs -20 dB (1
/ 10 times) attenuation.
【００２２】制御信号がＶｃ以下のときは、０ｄＢ（１
倍）で減衰しない。混合器５の出力５３は入力５１，５
２に対し周波数特性１０Ｈｚ〜４０ＫＨｚ（−３ｄＢ帯
域）、利得１倍（０ｄＢ）で入力信号をミキシングす
る。When the control signal is Vc or less, 0 dB (1
Do not decay at The output 53 of the mixer 5 is the input 51, 5
2, the input signal is mixed with a frequency characteristic of 10 Hz to 40 KHz (-3 dB band) and a gain of 1 (0 dB).
【００２３】図５は全波整流器８の入力８１の入力波形
で、時間軸０点が波形開始点を示し、波形Ｉが風雑音の
波形成分、波形ＩＩが風雑音に音響信号が重畳したもの
である。FIG. 5 is an input waveform of the input 81 of the full-wave rectifier 8, where the time axis 0 indicates the waveform start point, the waveform I is the waveform component of wind noise, and the waveform II is the wind noise with the acoustic signal superimposed. Is.
【００２４】図６は全波整流後の波形で図５のｔ1〜ｔ2
間の負電圧成分が正電圧成分に全波整流されている。FIG. 6 shows a waveform after full-wave rectification, and t 1 to t 2 in FIG.
The negative voltage component in between is full-wave rectified to the positive voltage component.
【００２５】図７は平滑時定数設定器１１により定めら
れた時定数τ0で、図６の波形が全波整流器８で平滑さ
れた出力８２の波形である。FIG. 7 shows the waveform of the output 82 obtained by smoothing the waveform of FIG. 6 by the full-wave rectifier 8 with the time constant τ 0 determined by the smoothing time constant setter 11.
【００２６】比較器９の入力９１には図７の波形が入力
され、基準電圧発生器１２で設定される電圧Ｖｔｈと比
較し、Ｖｔｈ以上のとき出力９２に図８の波形で出力さ
れる。The waveform shown in FIG. 7 is input to the input 91 of the comparator 9, compared with the voltage Vth set by the reference voltage generator 12, and when it is equal to or higher than Vth, the waveform shown in FIG. 8 is output to the output 92.
【００２７】アッテネータ制御回路１０の入力１０１に
図８の波形が入力され、立上り・立下り時定数設定器１
３により立上り時定数５ｍｓｅｃ以下、立下り時定数２
ｓｅｃ以上５ｓｅｃ以下で波形整形され、出力１０２に
図９の波形で出力される。その信号が電子式アッテネー
タ７のコントロール入力７３に入力される。The waveform of FIG. 8 is input to the input 101 of the attenuator control circuit 10, and the rising / falling time constant setter 1
3, rising time constant 5msec or less, falling time constant 2
The waveform is shaped in the range of sec to 5 sec, and the waveform of FIG. 9 is output to the output 102. The signal is input to the control input 73 of the electronic attenuator 7.
【００２８】図１０は、図９の時間ｔ7で電子式アッテ
ネータ７が動作したときの混合器５の出力５３（本例の
システムの出力）の出力波形である。風雑音が本例によ
り低減されている波形である。FIG. 10 is an output waveform of the output 53 of the mixer 5 (the output of the system of this example) when the electronic attenuator 7 operates at the time t 7 in FIG. This is a waveform in which wind noise is reduced by this example.
【００２９】（実施例２）実施例２としては、実施例１
の電子式アッテネータ７を電子式ボリュームに置き換
え、全波整流器８の出力８２を電子ボリュームの制御入
力に入力される。(Embodiment 2) As Embodiment 2, Embodiment 1 is used.
The electronic attenuator 7 is replaced with an electronic potentiometer, and the output 82 of the full-wave rectifier 8 is input to the control input of the electronic potentiometer.
【００３０】電子ボリュームの制御入力波形は図７であ
る。実施例２の場合、電子ボリュームの制御開始電圧が
Ｖｔｈに相当する。The control input waveform of the electronic volume is shown in FIG. In the case of the second embodiment, the control start voltage of the electronic volume corresponds to Vth.
【００３１】なお、電子ボリュームの最大減衰量は−２
０ｄＢ（１／１０倍）である。The maximum attenuation of the electronic volume is -2.
It is 0 dB (1/10 times).
【００３２】なお、平滑時定数設定器を有するため、風
雑音成分（２０Ｈｚ〜約１５０Ｈｚ）以上の周波数の雑
音，過大振幅に対し誤動作しない。Since the smoothing time constant setting device is provided, malfunction does not occur with respect to noise and excessive amplitude of wind noise components (20 Hz to about 150 Hz) or higher.
【００３３】[0033]
【発明の効果】以上説明したように本発明は風雑音が発
生したときのみ風雑音を最大−２０ｄＢ（１／１０倍）
低減できる効果を有する。As described above, according to the present invention, the maximum wind noise is -20 dB (1/10 times) only when the wind noise is generated.
Has the effect of being able to reduce.
【図１】本発明の一実施例を示すブロック図である。FIG. 1 is a block diagram showing an embodiment of the present invention.
【図２】風の音圧と周波数の関係を表わした図である。FIG. 2 is a diagram showing a relationship between wind sound pressure and frequency.
【図３】広帯域前置増幅器の特性を示す図である。FIG. 3 is a diagram showing the characteristics of a wideband preamplifier.
【図４】広帯分割器の特性を示す図である。FIG. 4 is a diagram showing characteristics of a wide band divider.
【図５】全波整流器の入力の信号波形を示す図である。FIG. 5 is a diagram showing a signal waveform of an input of a full-wave rectifier.
【図６】図５の全波整流後の波形を示す図である。FIG. 6 is a diagram showing a waveform after full-wave rectification in FIG.
【図７】全波整流器の出力の信号波形を示す図である。FIG. 7 is a diagram showing a signal waveform of an output of a full-wave rectifier.
【図８】比較器の出力の信号波形を示す図である。FIG. 8 is a diagram showing a signal waveform of an output of a comparator.
【図９】アッテネータ制御回路の出力の信号波形を示す
図である。FIG. 9 is a diagram showing a signal waveform of an output of the attenuator control circuit.
【図１０】混合器の出力の信号波形を示す図である。FIG. 10 is a diagram showing a signal waveform of an output of a mixer.
【図１１】従来のマイクロフォン増幅器を示すシステム
ブロック図である。FIG. 11 is a system block diagram showing a conventional microphone amplifier.
１ マイクロフォン ２ 広帯域前置増幅器 ３ 帯域分割器 ４ ２００Ｈｚ〜２０ＫＨｚ増幅器 ５ 混合器 ６ ２０Ｈｚ〜２００ＫＨｚ増幅器 ７ 電子式アッテネータ ８ 全波整流器 ９ 比較器 １０ アッテネータ制御回路 １１ 平滑時定数設定器 １２ 基準電圧発生器 １３ 立上り・立下り時定数設定器 1 Microphone 2 Broadband preamplifier 3 Band divider 4 200Hz-20KHz amplifier 5 Mixer 6 20Hz-200KHz amplifier 7 Electronic attenuator 8 Full wave rectifier 9 Comparator 10 Attenuator control circuit 11 Smoothing time constant setter 12 Reference voltage generator 13 Rising / falling time constant setter
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【手続補正書】[Procedure amendment]
【提出日】平成５年７月１９日[Submission date] July 19, 1993
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】発明の名称[Name of item to be amended] Title of invention
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【発明の名称】 風雑音低減マイクロフォン増幅装置Title: Wind noise reduction microphone amplification device
【手続補正３】[Procedure 3]
【補正対象書類名】図面[Document name to be corrected] Drawing
【補正対象項目名】図７[Name of item to be corrected] Figure 7
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【図７】 [Figure 7]
【手続補正４】[Procedure amendment 4]
【補正対象書類名】図面[Document name to be corrected] Drawing
【補正対象項目名】図８[Correction target item name] Figure 8
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【図８】 [Figure 8]
【手続補正５】[Procedure Amendment 5]
【補正対象書類名】図面[Document name to be corrected] Drawing
【補正対象項目名】図９[Correction target item name] Figure 9
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【図９】 [Figure 9]
【手続補正６】[Procedure correction 6]
【補正対象書類名】図面[Document name to be corrected] Drawing
【補正対象項目名】図１０[Name of item to be corrected] Fig. 10
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【図１０】 [Figure 10]
Claims (2)
信号を入力して次段への信号処理を行うに足る利得を有
する広帯域増幅器と、 前記増幅された音響信号を風雑音を主に含む周波数帯域
と人間の音声を主に含む周波数帯域とに分割する帯域分
割器と、 風雑音を主に含む帯域の増幅器の出力信号を風雑音があ
る場合に電子的に一定量減衰させる電子式アッテネータ
と、 風雑音検出のための全波整流器及び比較器と、 「風雑音有り」と判定した場合、前記電子式アッテネー
タを動作させるアッテネータ制御回路とを有することを
特徴とする風雑音（風吹かれノイズ）低減マイクロフォ
ン増幅装置。1. A wideband amplifier having a gain sufficient for inputting an acoustic signal containing wind noise (wind blowing noise) and performing signal processing to the next stage; and the amplified acoustic signal mainly including wind noise. A band divider that divides the frequency band that includes the human voice into a frequency band that mainly contains human voice, and an electronic formula that electronically attenuates the output signal of the amplifier in the band that mainly contains wind noise by a certain amount when there is wind noise. An attenuator, a full-wave rectifier and a comparator for wind noise detection, and an attenuator control circuit that operates the electronic attenuator when it is determined that “the wind noise is present”. Noise reduction microphone amplification device.
る全波整流器とを有することを特徴とする請求項１に記
載の風雑音（風吹かれノイズ）低減マイクロフォン増幅
装置。2. The electronic attenuator is replaced with an electronic volume that is electronically continuously attenuated, and a full-wave rectifier that extracts wind noise and generates a control voltage of the electronic volume. The microphone amplification device according to claim 1, wherein the wind noise is reduced.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20130091A JPH0629764A (en) | 1991-07-16 | 1991-07-16 | Wind noise reduction microphone amplifier |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20130091A JPH0629764A (en) | 1991-07-16 | 1991-07-16 | Wind noise reduction microphone amplifier |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0629764A true JPH0629764A (en) | 1994-02-04 |
Family
ID=16438710
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20130091A Pending JPH0629764A (en) | 1991-07-16 | 1991-07-16 | Wind noise reduction microphone amplifier |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0629764A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8509451B2 (en) | 2007-12-19 | 2013-08-13 | Fujitsu Limited | Noise suppressing device, noise suppressing controller, noise suppressing method and recording medium |
| US9357307B2 (en) | 2011-02-10 | 2016-05-31 | Dolby Laboratories Licensing Corporation | Multi-channel wind noise suppression system and method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100088257A1 (en) * | 2006-02-09 | 2010-04-08 | Yuan Lu | Systems and Methods for Generating Predicates and Assertions |
| JP2010148118A (en) * | 2002-07-08 | 2010-07-01 | Precache Inc | Routing method, routing apparatus, routing/caching method, routing/caching apparatus, and network |
| JP2012194833A (en) * | 2011-03-17 | 2012-10-11 | Fujitsu Ltd | Test data generating program, device, and method |
-
1991
- 1991-07-16 JP JP20130091A patent/JPH0629764A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010148118A (en) * | 2002-07-08 | 2010-07-01 | Precache Inc | Routing method, routing apparatus, routing/caching method, routing/caching apparatus, and network |
| US20100088257A1 (en) * | 2006-02-09 | 2010-04-08 | Yuan Lu | Systems and Methods for Generating Predicates and Assertions |
| JP2012194833A (en) * | 2011-03-17 | 2012-10-11 | Fujitsu Ltd | Test data generating program, device, and method |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8509451B2 (en) | 2007-12-19 | 2013-08-13 | Fujitsu Limited | Noise suppressing device, noise suppressing controller, noise suppressing method and recording medium |
| US9357307B2 (en) | 2011-02-10 | 2016-05-31 | Dolby Laboratories Licensing Corporation | Multi-channel wind noise suppression system and method |
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