Noise suppressing device, noise suppressing controller, noise suppressing method and recording medium

A noise suppressing device being operable with a plurality of sound receiving units for outputting a plurality of sound signals based on received sound, and that suppresses noise in the sound received by the sound receiving units, the noise suppressing device comprising:

• a suppressing unit for suppressing noise by subtracting the noise component derived on the basis of the plurality of sound signals output by the sound receiving units;
• a variation deriving unit for deriving a degree of variation by numerically quantizing the variation on the basis of an amplitude spectrum obtained by converting the plurality of sound signals to components on the frequency axis;
• a determining unit for determining whether or not the degree of variation is equal to or greater a specified variation threshold value;
• and
• an adjusting unit that adjusts the amount of suppression when the determining unit determines that the degree of variation is equal to or greater than the variation threshold value;
• wherein
• the suppressing unit suppresses noise by subtracting the noise component from the sound signals on the basis of the amount of suppression adjusted by the adjusting unit,
• wherein the determining is performed in accordance with
• 1
• ω
• 3
• -
• ω
• 2
• ⁢
• ∑
• ω
• 2
• ω
• 3
• ⁢
• ϕ
• ⁡
• (
• ω
• )
• 2
• >
• β
• where ω is frequency, φ is phase difference and β is the variation threshold value, and where ω2 is a third frequency and ω3 is a fourth frequency higher than ω2.

A noise suppressing controller for controlling a suppressing unit for suppressing a noise component in the sound received by the plurality of the sound receiving units on the basis of a plurality of sound signals output by the sound receiving units, comprising:

• a variation deriving unit for deriving a degree of variation by numerically quantizing the variation on the basis of an amplitude spectrum obtained by converting the plurality of sound signals to components on the frequency axis;
• a determining unit for determining that wind noise is occurring due to wind blowing against the sound receiving units, when the degree of variation derived by the variation deriving unit is equal to or greater than a variation threshold value;
• and
• a suppressing control unit for outputting, according to the decision of the determining unit about whether or not wind noise is occurring, an instruction to the suppressing unit to adjust the amount of suppression,
• wherein the determining is performed in accordance with
• 1
• ω
• 3
• -
• ω
• 2
• ⁢
• ∑
• ω
• 2
• ω
• 3
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• ϕ
• ⁡
• (
• ω
• )
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• >
• β
• where ω is frequency, φ is phase difference and β is the variation threshold value, and where ω2 is a third frequency and ω3 is a fourth frequency higher than ω2.

A noise suppressing method using a computer being operable with a plurality of sound receiving units for outputting a plurality of sound signals based on received sound, that suppresses noise in the sound received by the sound receiving units, the noise suppressing method comprising:

• deriving, using the computer, a degree of variation by numerically quantizing the variation on the basis of an amplitude spectrum obtained by converting the plurality of sound signals to components on the frequency axis;
• determining, using the computer, that wind noise due to wind blowing against the sound receiving units is occurring when the derived degree of variation is equal to or greater than a variation threshold value;
• and
• adjusting, using the computer, the amount of suppression according to the decision about whether or not there is wind noise,
• wherein the determining is performed in accordance with
• 1
• ω
• 3
• -
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• 2
• ⁢
• ∑
• ω
• 2
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• ⁡
• (
• ω
• )
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• >
• β
• where ω is frequency, φ is phase difference and β is the variation threshold value, and where ω2 is a third frequency and ω3 is a fourth frequency higher than ω2.

A non-transitory computer-readable recording media storing a program for making a computer function as a noise suppressing device being operable with a plurality of sound receiving units for outputting a plurality of sound signals on the basis of the received sound, and that suppresses noise in the sound received by the sound receiving units, the program comprising:

• deriving a degree of variation by numerically quantizing the variation on the basis of an amplitude spectrum obtained by converting the plurality of sound signals to components on the frequency axis;
• determining whether or not the degree of variation derived by the variation deriving unit is equal to or greater than a specified variation threshold;
• and
• adjusting the amount of suppression when it is determined that the degree of variation is equal to or greater than the variation threshold,
• wherein the determining is performed in accordance with
• 1
• ω
• 3
• -
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• 2
• ⁢
• ∑
• ω
• 2
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• 3
• ⁢
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• ⁡
• (
• ω
• )
• 2
• >
• β
• where ω is frequency, φ is phase difference and β is the variation threshold value, and where ω2 is a third frequency and ω3 is a fourth frequency higher than ω2.

A noise suppressing device being operable with a plurality of sound receiving units for outputting a plurality of sound signals based on received sound, and that suppresses noise in the sound received by the sound receiving units, comprising:

• a suppressing unit for suppressing noise by subtracting a noise component derived on the basis of the plurality of sound signals output by the sound receiving units from the sound signals;
• a variation deriving unit for deriving a degree of variation by numerically quantizing the variation on the basis of an amplitude spectrum obtained by converting the plurality of sound signals to components on a frequency axis;
• a determining unit for determining that wind noise is occurring due to wind blowing against the sound receiving units when the degree of variation is equal to or greater than a specified variation threshold value;
• and
• an adjusting unit for adjusting an amount of suppression according to the decision of the determining unit about whether or not wind noise is occurring;
• wherein
• the suppressing unit suppresses noise by subtracting the noise component from the sound signals based on the amount of suppression adjusted by the adjusting unit,
• wherein the determining is performed in accordance with
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• 1
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• 2
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• (
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• γ
• where S1 is a first amplitude spectrum, S2 is a second amplitude spectrum, ω is frequency and γ is the variation threshold value, and where ω0 is a first frequency and ω1 is a second frequency higher than ω0.