Technical field
[0001]This technique is a signal processing apparatus and method, and a program, the signal processing apparatus and method capable of improving the noise canceling performance, and a program.
BACKGROUND
[0002]Noise canceling technique is studied for a long time, now the headphone noise canceling function is mounted is put into practical use, widespread.
[0003]
　In recent years, as the noise canceling technology, surrounds the control region using a number of loudspeakers and microphones, it has been made to suppress studied noise in a wider area. Thus for example in a car or in an aircraft is considered possible to keep quiet large areas like.
[0004]
　Usually, since the frequency characteristic of the noise is unknown, generally adaptive filter is used in the noise canceling.
[0005]
　The coefficients of the adaptive filter update is required noise signal obtained by the reference microphone and the error microphone. Noise input to these microphones are usually assumed invading from the control area outside the control area inside. However, noise is generated in the control region inside unintentionally, it is conceivable to become picked up by the microphone.
[0006]
　When the noise generated in the control region inside the reference microphone and the error microphone is detected as the adaptive filter to diverge, noise canceling performance is lowered.
[0007]
　Therefore, a method using a single-directional microphone to the reference microphone or error microphone has been proposed (e.g., see Non-Patent Document 1).
[0008]
　In this method, by directing the directivity of the microphone on the outside of the control region, and ideally it can be made to be not affected by the noise received from the control area inside.
CITATION
Non-patent literature
[0009]
非特許文献1 : Christian Kleinhenrich, Detlef Krahe, “The Reflection Equivalence Formulation for a circular ANC System,” Proceedings of INTER-NOISE 2016. 2016.
Summary of the Invention
Problems that the Invention is to Solve
[0010]
　However, in the above-described technique it is difficult to obtain a sufficient noise canceling performance.
[0011]
　For example, the method using the unidirectional microphone is to make a microphone that has an actual complete unidirectional difficult, will receive no small influence of noise transmitted from the control area inside.
[0012]
　Further, From the order it is difficult to maintain the frequency characteristic flat in microphone with unidirectional generally well gain low is reduced, since larger variations between microphones individuals, exactly sound field it is difficult to. Then, there is a noise canceling performance deteriorates.
[0013]
　This technology has been made in view of such circumstances, it is desirable to make it possible to improve the noise canceling performance.
Means for Solving the Problems
[0014]
　Signal processing apparatus according to an embodiment of the present technology, a noise detector for detecting the control area noise generated in the control region formed by the microphone array, the external noise to the noise canceling region formed by the speaker array the updating of the filter coefficients of the adaptive filter used for generating the signal of the output sound output by the speaker array in order to reduce, and a control section for controlling, based on the control area the noise detection result.
[0015]
　The signal processing apparatus, a signal obtained by sound pickup by the microphone array, an adaptive filter unit for generating a signal of the output sound can be further provided on the basis of said filter coefficients.
[0016]
　Wherein the adaptive filter section, in the spatial frequency domain, wherein to perform the filtering processing based on the obtained signal and the filter coefficients by sound pickup by the microphone array, it is possible to generate a signal of the output sound.
[0017]
　Said control section, when the control area the noise by the noise detecting unit is detected, it is possible to ensure updates the filter coefficients is not performed.
[0018]
　Wherein the noise detecting unit, on the basis of the signal obtained by sound pickup by the microphone array, it is possible to detect the control area noise.
[0019]
　The said noise detecting unit, wherein the configuring the microphone array, on the basis of the respective signals obtained by sound pickup by each of the plurality of microphone array which distance is different from the center position of the control region, the control region It may detect the noise.
[0020]
　Wherein the noise detecting unit, and a signal obtained by sound pickup by the microphone array, in a signal obtained by sound pickup by different other microphone array distance between the microphone array from the center position of the control region based on, it is possible to detect the control area noise.
[0021]
　Wherein the noise detecting unit, based on a signal obtained by sound pickup by detecting microphone disposed in the control region, it is possible to detect the control area noise.
[0022]
　The microphone array may be those obtained by arranging a plurality of microphone array in a predetermined shape.
[0023]
　The speaker array, can be those obtained by arranging a plurality of the speaker array into a predetermined shape.
[0024]
　The control region may be a region formed by reference microphone array or error microphone array as the microphone array.
[0025]
　Signal processing method or program according to an embodiment of the present technology detects control area noise generated in the control region formed by the microphone array, reducing the external noise to the noise canceling region formed by the speaker array comprising the step of the updating of the filter coefficients of the adaptive filter used for generating the signal of the output sound output by the speaker array, is controlled based on the control area the noise detection result to.
[0026]
　In one aspect of the present technology, it is detected within the controlled area noise generated in the control region, which is formed by the microphone array, the speaker array in order to reduce the external noise to the noise canceling region formed by the speaker array updating of the filter coefficients of the adaptive filter used for generating the signal of the output sound output by is controlled based on the control area the noise detection result.
The invention's effect
[0027]
　According to the embodiments of the present technology, it is possible to improve the noise canceling performance.
[0028]
　Here, the advantages described in the present invention is not necessarily limited, it may be any of the effects described in the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029]
[1] is a diagram for explaining the technology.
FIG. 2 is a diagram illustrating a feedforward ANC system.
It is a diagram illustrating a configuration example of FIG. 3 spatial noise control device.
Is a diagram illustrating FIG. 4 coordinate system.
5 is a diagram for explaining the control areas.
Is a flowchart illustrating a FIG. 6 noise canceling process.
7 is a diagram showing a configuration example of a spatial noise control device.
8 is a diagram illustrating a control region.
Is a flowchart illustrating a FIG. 9 noise canceling process.
[10] Referring microphone array is a diagram for explaining another example of the speaker array, and an error microphone array.
[11] Referring microphone array is a diagram for explaining another example of the speaker array, and an error microphone array.
12 is a diagram illustrating another example of the speaker array and error microphone array.
13 is a diagram for explaining another example of the speaker array and error microphone array.
14 is a diagram illustrating another example of a reference microphone array and error microphone array.
15 is a diagram for explaining another example of the speaker array.
[16] Referring microphone array is a diagram for explaining another example of the speaker array, and an error microphone array.
17 is a diagram illustrating another example of a reference microphone array.
18 is a diagram illustrating another example of the error microphone array.
It is a diagram illustrating a configuration example of FIG. 19 computer.
DESCRIPTION OF THE INVENTION
[0030]
　Hereinafter, with reference to the accompanying drawings, a description will be given of an embodiment according to the present technology.
[0031]

　This technique detects the noise generated in the control region inside, by controlling the update of the adaptive filter in accordance with the detection result, noise in the control region inside prevents the divergence of the adaptive filter even if it occurs, it is to be able to improve the noise canceling performance.
[0032]
　First, an outline of noise canceling according to the present technique with reference to FIG.
[0033]
　In the example shown in FIG. 1, the error microphone 111 to the error microphone 11-8 so as to surround the position where there are predetermined user U11 and are arranged in annular, their error microphones 11-1 to error microphone 11-8 error microphone array 12 is constituted by.
[0034]
　In the following description, when it is particularly necessary to distinguish between the error microphone 111 to the error microphone 11-8, simply and also referred to as error microphone 11.
[0035]
　The speaker 13-1 to the speaker 13-4 to surround the error microphone array 12 are arranged and disposed so as to ring, their speaker 13-1 to the speaker array 14 from the speaker 13-4 is configured .
[0036]
　Hereinafter, when it is not necessary to distinguish the speakers 13-1 to the speaker 13-4, simply and also referred to as a speaker 13.
[0037]
　Furthermore, so as to surround the speaker array 14, the reference microphones 15-1 to reference microphone 15-8 has arranged annularly, the reference microphone array 16 is constituted by their reference microphone 15-1 to reference microphone 15-8 ing.
[0038]
　In the following description, when reference microphone 15-1 to the reference microphone 15-8 is not particularly necessary to distinguish, simply and also referred to as a reference microphone 15.
[0039]
　In this example, the region surrounded by the error microphone 11, i.e. the inner region or the region surrounded by the reference microphone 15, i.e. the control region inside the area of ​​the reference microphone array 16 is detected in the noise, the error microphone array 12 It is.
[0040]
　Here, for example, the position indicated by the arrow A11, generated in the control region, when it is assumed that the noise (sound) propagated to the outside of the control region is referred to as a control area noise, the detection target of the control area the control area noise to be a region. Control area noise, for example, to the user U11 is talking, generated by or stuck.
[0041]
　In contrast, for example, the position indicated by the arrow A12, occurs outside the control area, the noise that propagates to the control region (sound) will be referred to as external noise. The external noise is subject to the sound of the noise canceling, in particular propagation path of external noise from the source of the external noise until the error microphone 11 is referred to as the primary path.
[0042]
　The area surrounded by the speaker 13 in this example, i.e. the inner region of the speaker array 14, a region to be noise canceling, the following will be referred to as the region noise canceling region both.
[0043]
　During noise canceling, by outputting a sound that cancels noise, especially external noise from the speaker array 14, noise noise canceling region is reduced (canceled), noise canceling can be achieved. In this case, in particular is such external noise is canceled, the control area noise are not subject to reduction (cancellation).
[0044]
　Incidentally, the propagation path between the transmission path to the error microphone 11 of the output sound from the speaker 13, i.e. from the speaker 13 to the error microphone 11 is called a secondary path.
[0045]
　For example, noise canceling, the adaptive filter is used. This external noise to be canceled subject is not a known noise determined in advance.
[0046]
　During updating of the filter coefficients of the adaptive filter, a reference signal obtained by picking up sound by reference microphone array 16, on the basis of the error signal obtained by picking up sound by the error microphone array 12 filter coefficient is calculated.
[0047]
　Here, the reference signal is mainly a signal consisting of components of external noise, the error signal is predominantly signal representing the difference between the component and the external noise component of the sound output from the speaker array 14.
[0048]
　From the speaker array 14, using the filter coefficients obtained in this way, the sound based on the signal obtained by the filtering processing to the reference signal is output, so that the external noise is reduced by the sound.
[0049]
　The control region as described above, control area noise to cause the user U11 and the like are generated. Control area noise is a noise that propagates to the control area outside the control region, it is difficult to its propagation direction is controlled to become the opposite direction to the propagation direction of the sound output from the speaker 13. That is, for example, a control area or noise cancel control entire region by the sound output from the speaker array 14, it is difficult or cancel only the error microphone 11 near the region.
[0050]
　Such control area noise will be caused to diverge the adaptive filter and mixed from unintended direction error microphone 11 and reference microphones 15, there appropriate filter coefficients possibly not be obtained.
[0051]
　Therefore, in this technique, to detect a control region within the noise, when the control area the noise is detected, the process of updating the adaptive filter, i.e. by stopping the adaptive processing, and to improve the noise canceling performance .
[0052]

　or less, more specifically described the present technology.
[0053]
　First, general feed-forward type ANC (Active Noise Controll) the system will be described.
[0054]
　Figure 2 shows a block diagram of the ANC system common feedforward.
[0055]
　The feedforward ANC system, a reference signal obtained by the reference microphone x (n t with respect to), the estimated value in the form of the estimated secondary path is multiplied by the obtained signal x of the secondary path '(n t ) and the error signal e (n t filter coefficients of the adaptive filter by LMS (Least Mean Squares) based on the) is calculated.
[0056]
　Then, in the adaptive filter reference signal x (n t filtering processing by the filter coefficients obtained by LMS is performed on) is output sound for noise canceling speaker based on the resulting signal . Signal y of the sound output from the speaker (n t ) is the signal y '(n through the secondary path t ) becomes, is picked up by the error microphone. At the same time, the reference signal x (n is an external noise t ) be the signal d (n through the primary path t is picked up by) and the error microphone.
[0057]
　Thus collected by the error microphone signal d (n t ) and the signal y '(n t ) because signal serving a new error signal e (n t ), and this error signal e (n t ) is It is supplied to the LMS.
[0058]
　Such ANC system is especially called Filtered-X LMS algorithm. It should be noted that, for the Filtered-X LMS algorithm, for example, "Morgan DR," An analysis of multiple correlation cancellation loops with a filter in the auxiliary path, "IEEE Trans. Acoust. Speech Signal Process., ASSP28 (4), 454-467 , 1980. "are described in detail in such.
[0059]
　Now, the error signal in the time-frequency domain as the angular frequency omega, the primary path, the secondary path, the filter coefficients of the adaptive filter, and a reference signal, respectively E (ω), P (ω), S (ω), W ( omega), and when the X (omega), the error signal E (omega) is expressed by the following equation (1).
[0060]
[Number 1]

[0061]
　It means that the noise is completely canceled (removed) when the error signal E (omega) = 0 ideally, the filter coefficient of the ideal adaptive filter W ideal (omega) is the following formula (2) It is shown.
[0062]
[Number 2]

[0063]
　However, since it is difficult to obtain a filter coefficient of the adaptive filter in consideration of the secondary path S (omega) itself without delay, is an estimate of the secondary path secondary path model S '(ω) is used updating of the filter coefficients is performed.
[0064]
　Considering the time domain, the error signal e (n t ) is expressed by the following equation (3).
[0065]
[Number 3]

[0066]
　In the equation (3), n t denotes a time index, d (n t ) denotes the signal of the external noise picked up on the error microphone through the primary path, s (n t ) shows the impulse response of the secondary path S (ω) it is. Further, in the equation (3) * indicates a linear convolution operation, w (n t ) denotes the filter coefficient of the adaptive filter, x (n t ) represents the reference signal.
[0067]
　Filter coefficients of the adaptive filter w (n t ) is the error signal e (n, as shown in the following equation (4) t squared error xi] '(n in) t is updated to minimize).
[0068]
[Formula 4]

[0069]
　For example, using the steepest descent method, the filter coefficients of the adaptive filter may be updated as shown in the following equation (5).
[0070]
[Formula 5]

[0071]
　In the equation (5), w (n t ) denotes the filter coefficient before updating, w (n t +1) indicates a filter coefficient after updating. Also shows the step size μ in the equation (5), ∇Kushi '(n t ) is the error signal e (n t indicates the gradient of the squared error).
[0072]
　Here, the gradient of the squared error ∇Kushi '(n t ) is represented as shown in the following equation (6).
[0073]
[Number 6]

[0074]
　Incidentally, x in the formula (6) '(n t ) is as shown in the following equation (7). Equation (7), the s '(n t ) is the secondary path model S' represents the impulse response of (omega).
[0075]
[Number 7]

[0076]
　By substituting equation (6) in the above equation (5), the filter coefficients w (n shown in the following equation (8) t updating expressions) are obtained.
[0077]
[Number 8]

[0078]
　The feedforward ANC system, the filter coefficients of the adaptive filter is updated update equation is used as shown in equation (8).
[0079]

　Next, a specific embodiment to which the present technique is applied to the feedforward ANC system.
[0080]
　Figure 3 is a diagram showing a configuration example of an embodiment of a spatial noise control device according to the present technology.
[0081]
　The spatial noise control device 71 utilizes a feedforward ANC system updates the filter coefficient of the adaptive filter, the signal processing device which realizes noise cancellation in the noise canceling region using the obtained filter coefficients is there.
[0082]
　Spatial noise controller 71, the reference microphone array 81, time-frequency analysis unit 82, the spatial frequency analysis unit 83, the estimated secondary path adding section 84, error microphone array 85, time-frequency analysis unit 86, the spatial frequency analysis unit 87, the control region noise detection unit 88, the adaptive filter coefficient calculation unit 89, the adaptive filter section 90 has a spatial frequency synthesizing unit 91, a time-frequency synthesis unit 92 and the speaker array 93,.
[0083]
　Referring microphone array 81, for example, corresponds to a reference microphone array 16 shown in FIG. 1, a microphone array obtained by a plurality of microphones arranged such as annular or spherical. Referring microphone array 81 picks up external sounds, and supplies a reference signal obtained as a result the time-frequency analyzer 82. The reference signal is an audio signal consisting of primarily components of external noise emitted from the noise source.
[0084]
　Time-frequency analysis unit 82 performs a time-frequency conversion on the reference signal supplied from the reference microphone array 81, and supplies the time-frequency spectrum of the resulting reference signal to the spatial frequency analyzer 83.
[0085]
　Spatial frequency analysis unit 83 performs a spatial frequency transform on the time-frequency spectrum of the reference signal supplied from the time-frequency analysis unit 82, the estimated spatial frequency spectrum of the resulting reference signal secondary path adding section 84 and supplies to the adaptive filter unit 90.
[0086]
　Estimated secondary path adding section 84, the spatial frequency spectrum of the estimated secondary path is an estimate of the secondary path with respect to the spatial frequency spectrum of the reference signal supplied from the spatial frequency analyzer 83, i.e. the secondary path model multiplying, and supplies the resulting spatial frequency spectrum in the adaptive filter coefficient calculation unit 89.
[0087]
　Error microphone array 85 may for example correspond to the error microphone array 12 shown in FIG. 1, a microphone array obtained by a plurality of microphones arranged such as annular or spherical. Error microphone array 85 picks up external sounds, and supplies the error signal obtained as a result the time-frequency analyzer 86.
[0088]
　Incidentally, the error signal is predominantly the component of the external noise emitted from the noise source, the audio signal comprising a component of the output sound from the speaker array 93.
[0089]
　Here, the sound output from the speaker array 93, cancel out external noise, that is, sound for canceling. Therefore, it is possible that the error signal represents the error between the noise canceling component that could not cancel external noise during, that external noise and the sound output from the speaker array 93.
[0090]
　Time-frequency analysis unit 86 performs a time-frequency conversion on the error signal supplied from the error microphone array 85, and supplies the time-frequency spectrum of the resulting error signal to the spatial frequency analyzer 87.
[0091]
　Spatial frequency analysis unit 87 performs a spatial frequency transform on the time-frequency spectrum of the error signal supplied from the time-frequency analysis unit 86, the spatial frequency spectrum of the resulting error signal to the adaptive filter coefficient calculation unit 89 supplies.
[0092]
　Control area the noise detection unit 88, for example, a sensor signal which is an output of the sensor, such as located in a control area camera, based on the collected sound signal or the like which is the output of the detection microphone located in a control region , detecting the control area noise generated in the control region. The control area the noise detection unit 88 supplies the noise detection signal indicating the detection result of the control area the noise to the adaptive filter coefficient calculation unit 89.
[0093]
　Adaptive filter coefficient calculation unit 89, based on the supplied noise detection signal from the control area the noise detection unit 88 functions as a control unit for controlling the updating of the filter coefficients of the adaptive filter.
[0094]
　In other words, the adaptive filter coefficient calculation unit 89, in response to the noise detection signal, adaptation and the spatial frequency spectrum of the estimated secondary path adding section 84, based on the spatial frequency spectrum of the error signal from the spatial frequency analyzer 87 filter calculating a filter coefficient, and supplies to the adaptive filter unit 90. Filter coefficients of the adaptive filter obtained by the adaptive filter coefficient calculation unit 89 is ideally filter coefficients of a filter having the inverse characteristic of the secondary path.
[0095]
　Such filter coefficients of the adaptive filter to reduce the external noise in the noise canceling region, i.e. to cancel (cancel) used to generate the speaker drive signal output sound output from the speaker array 93 in order.
[0096]
　Adaptive filter 90 uses the filter coefficient of the adaptive filter which is supplied from the adaptive filter coefficient calculation unit 89 performs filtering processing on the spatial frequency spectrum of the reference signal supplied from the spatial frequency analyzer 83, as a result the spatial frequency spectrum of the loudspeaker drive signal supplied to the spatial frequency synthesizing unit 91. In this case, the adaptive filter section 90, in the spatial frequency domain, the filtering processing based on the reference signal and the filter coefficients is performed, so that the loudspeaker drive signal is generated.
[0097]
　Spatial frequency synthesizing unit 91, the spatial frequency spectrum supplied from the adaptive filter unit 90 and the spatial frequency synthesis, and supplies the time-frequency spectrum of the resulting speaker driving signals time-frequency synthesis unit 92.
[0098]
　Time frequency synthesizer unit 92, the time-frequency spectrum of the loudspeaker drive signal supplied from the spatial frequency synthesizing unit 91 and time-frequency synthesis, and supplies the loudspeaker drive signal a resulting time signal to the speaker array 93.
[0099]
　Speaker array 93 corresponds to, for example, the speaker array 14 shown in FIG. 1, a speaker array obtained by a plurality of speakers arranged like in an annular or spherical. Speaker array 93 outputs a sound based on the speaker drive signal supplied from the time-frequency synthesis unit 92.
[0100]
　The reference microphone array 81, error microphone array 85, and arrangement of the speaker array 93 is for example, see the microphone array 16 in FIG. 1, the error microphone array 12, and as the same as the arrangement of the speaker array 14 .
[0101]
　That is placed speaker array 93 so as to surround the error microphone array 85, the reference microphone array 81 are arranged so as to further its speaker array 93 is enclosed.
[0102]
　As will be described in detail later, wherein the area formed by the reference microphone array 81, i.e. the region surrounded by the reference microphone array 81 is a control area. The region formed by the speaker array 93, that is, the region surrounded by the speaker array 93 is a noise canceling region.
[0103]
　Will now be described in more detail the components constituting the spatial noise control device 71.
[0104]
(Time-frequency analysis unit)
　will be described first time-frequency analyzer 82.
[0105]
　In the time-frequency analysis unit 82, the reference signals the microphones is obtained by sound pickup constituting the reference microphone array s 81 (q, n t ) time-frequency transform on is performed.
[0106]
　That is, the time-frequency analysis unit 82, by performing the calculation of equation (9), DFT (Discrete Fourier Transform) performs time-frequency conversion using the (discrete Fourier transform), the reference signal s (q, n t ) from the time frequency spectrum S (q, n tf ) determined.
[0107]
[Number 9]

[0108]
　In the expression (9), q denotes the microphone index identifying a microphone which constitutes the reference microphone array 81, q = 0, 1, 2, ..., a Q-1. Also, Q is represents the number of microphones is the number of microphones constituting the reference microphone array 81, n t denotes a time index. Further, n tf represents time frequency index, M t denotes the number of samples of DFT, i denotes the pure imaginary number.
[0109]
　Time-frequency analysis unit 82, the time period the frequency spectrum obtained by the frequency conversion S (q, n tf ) for supplying spatial frequency analyzer 83.
[0110]
　Also in the time-frequency analysis unit 86, the time-frequency conversion on the error signal is performed the same calculation as in the time-frequency analyzer 82 is performed.
[0111]
(Spatial frequency analysis unit)
　spatial frequency analysis unit 83, the shape of the reference microphone array 81, i.e. the reference according to the arrangement shape of the microphone constituting the microphone array 81, time-frequency analysis unit 82 is supplied from the time frequency spectrum S ( Q, N Tf ) the spatial frequency analysis. That is, the time-frequency spectrum S (q, n tf ) spatial frequency transformation on is performed.
[0112]
　For example when the reference microphone array 81 is annular microphone array, computation is performed spatial frequency transformation of the formula (10) is performed.
[0113]
[Formula 10]

[0114]
　In the equation (10), S 'indicates the vector of spatial frequency spectrum, Q is represents the number of microphones of the reference microphone array 81, J inv shows a matrix of spherical Bessel functions.
[0115]
　Also, E mic is a matrix consisting of the cyclic harmonics (circular harmonic function), E H mic is a matrix E mic shows a Hermitian transposed matrix of, S is the reference signal time frequency spectrum S (q, n tf ) It shows the vector.
[0116]
　Specifically, the vector S of the spatial frequency spectrum 'is expressed by the following equation (11).
[0117]
[Number 11]

[0118]
　In the formula (11), S ' n (n tf ) (where, n = -N, -N + 1 , ..., N) represents a spatial frequency spectrum of the reference signal. Spatial frequency spectrum S ' n (n tf n in) represents the order of the spatial frequency, in particular N represents the maximum degree of spatial frequency. Further, n in formula (11) tf represents time frequency index.
[0119]
　Furthermore, the matrix J consists spherical Bessel functions in Equation (10) inv is, for example, those represented by the formula (12), a matrix E consisting of cyclic harmonics mic is expressed by the following equation (13) It is things.
[0120]
[Number 12]

[0121]
[Formula 13]

[0122]
　In the equation (12), j n denotes a spherical Bessel function order of the spatial frequency is n, c denotes the speed of sound, r mic is the radius of the reference microphone array 81 is annular microphone array shows, ω represents the angular frequency.
[0123]
　Further, in the equation (13), i denotes a pure imaginary number, n (where, n = -N, -N + 1 , ..., N) denotes the order of the spatial frequency, phi q reference microphone microphone index array 81 indicates the azimuthal position of the microphone is q.
[0124]
　Here, a description will be given azimuth and elevation of the microphone positions.
[0125]
　For example with reference to the origin O, as shown in FIG. 4, x-axis, the y-axis, and the z-axis consider a three-dimensional orthogonal coordinate system with each axis.
[0126]
　Now, a straight line connecting the predetermined microphone MU11 constituting the reference microphone array 81 and the origin O to the straight line LN, and the straight line LN 'a straight line obtained by projecting the straight line LN from the z-axis direction in the xy plane.
[0127]
　In this case, the angle φ between the x axis and the straight line LN 'is an azimuth angle indicating a direction of a position of the microphone MU11 viewed from the origin O in the xy plane. Further, the angle between the z axis and the straight line LN theta is the angle of elevation showing the position of the microphone MU11 viewed from the origin O in the xy plane perpendicular to the plane.
[0128]
　Furthermore, the vector S in the equation (10) described above is represented by the following formula (14).
[0129]
[Number 14]

[0130]
　In Equation (14), the vector S is the time-frequency spectrum S (q, n of a reference signal obtained by the microphones of the reference microphone array 81 tf has a vector) of the element.
[0131]
　Also, see, for example, the microphone array 81 may be spherical microphone array, spatial frequency transformation is performed is performed the calculation of the following equation (15).
[0132]
[Number 15]

[0133]
　In the equation (15), S 'is the vector of spatial frequency spectrum shown in equation (11), Q denotes the number of microphones of the reference microphone array 81, J inv is shown in Formula (12) it is a matrix of spherical Bessel functions.
[0134]
　Further, Y mic is a matrix consisting of spherical harmonics, Y H mic is a matrix Y mic indicates Hermitian transpose matrix of the time-frequency spectrum of the reference signal S shown in Equation (14) S (q, n tf is a vector of).
[0135]
　Here, the elevation and azimuth position of the microphone microphone index reference microphone array 81 is q theta q and phi q and the spherical harmonics orders of the spatial frequency is n and m Y n m (theta q , Fai Q and).
[0136]
　In this case, matrix Y consisting of spherical harmonics mic is expressed by the following equation (16). Incidentally, N and M in equation (16) represents the maximum order of spatial frequency.
[0137]
[Number 16]

[0138]
　The spatial frequency analyzer 83, the formula (10) or Formula spatial frequency spectrum obtained by the spatial frequency conversion shown in (15) S ' n (n tf outputs a). Also in the spatial frequency analyzer 87, the spatial frequency conversion by the same calculation as that in the spatial frequency analyzer 83 (spatial frequency analysis) is performed.
[0139]
(Control area noise detection unit)
　in the control area the noise detection unit 88, detection is performed in the control area the noise, the noise detection signal indicating the detection result is generated.
[0140]
　Here, the control region is a region formed by the reference microphone array 81 as shown in FIG. 5, for example, that is, a region surrounded by reference microphone array 81. Note that portions corresponding to the case in FIG. 3 in FIG. 5 are denoted by identical reference numerals, and description thereof will be omitted as appropriate.
[0141]
　In the example shown in FIG. 5, the speaker array 93 and error microphone array 85 in the region surrounded by the microphones of the reference microphone array 81 is disposed.
[0142]
　The spatial noise control device 71, the inner portion of the reference microphone array 81 which hatch has been applied, that is, a range of a portion surrounded by each microphone is a control region, noise generated in the control region (sound) is detected that.
[0143]
　For example, the control area the noise detection unit 88, a sensor signal output from the camera for capturing the control area as a subject, that detects the user control region based on the image data, detects the movement of the mouth of the user .
[0144]
　The control area the noise detection unit 88, when the movement of the user's mouth is detected, generates a noise detection signal indicating that the control area noise is detected, when the movement of the user's mouth is not detected , and it generates a noise detection signal indicating that the control area the noise is not detected.
[0145]
　Further, for example, to set up the detecting microphone to the control region, and mounting or detecting microphone to the user's control region, yield the control area the noise detection unit 88 is output from one or more sensing microphone it may detect the control area noise based on the sound signal.
[0146]
　In this case, for example, the control area the noise detection unit 88 may detect the presence or absence of control region noise from such temporal change in sound pressure of sound based on the sound collection signal.
[0147]
　Furthermore, for example, each other installation position is different detection microphone, the reference microphone array 81, and any with two of the error microphone array 85, based on the sound pressure ratio or the like of the sound based on the signal outputted from the two microphones control area noise Te may be detected. In this case, if necessary, leave comparing like sound pressure of sound based on the signal outputted from the pre-two microphones, it is possible to make use in an appropriate noise detection also the result of the comparison.
[0148]
　For example reference when detecting the control area the noise by using the microphone array 81 and error microphone array 85, and when the control area noise is picked up, and when the external noise picked up the reference microphone array 81 and the sound pressure is obtained differs between the error microphone array 85. That is, for example, when the control area noise is picked up, rather than the sound pressure at the reference microphone array 81, since it should sound pressure at the error microphone array 85 is increased, using the relationship of such sound pressure it may be detected within the controlled area noise by.
[0149]
　Thus and the detection microphone, the reference microphone array 81, such as error microphone array 85, the distance from the center position of the control area to detect a control region within the noise based on the output of a plurality of different microphone arrays (microphones) it is also possible.
[0150]
　Other, in the control area the noise detection unit 88, a sound source position estimation and DOA estimation using microphone arrays (DOA (Direction of Arrival Estimation)), so that such a control area noise combinations such as those techniques is detected it may be. The detection method of the control area the noise may be any method.
[0151]
　When the presence of the control area the noise as described above is detected, the control area the noise detection unit 88 supplies the noise detection signal indicating the detection result to the adaptive filter coefficient calculation unit 89.
[0152]
(Adaptive filter coefficient calculating part)
　in the adaptive filter coefficient calculation unit 89, based on the spatial frequency spectrum of the error signal, and the spatial frequency spectrum of the reference signal spatial frequency spectrum is multiplied by the estimated secondary path, the adaptive filter filters coefficients are updated.
[0153]
　However, when the noise detection signal indicating that the control area noise is detected is supplied from the control area the noise detection unit 88, updating of the filter coefficients is not performed. That is, when the control area noise control area is detected, updating of the filter coefficients is adapted not performed.
[0154]
　For example, the time index n t and the time-frequency index n tf as the spatial frequency spectrum of the error signal output from the spatial frequency analyzer 87 S ' n err (n t , n tf and represented) and. Here, n is the order of the spatial frequency.
[0155]
　At this time, 'the spatial frequency spectrum S of the error signal in the following equation (17) n err (n t , n tf square error ξ of)' (n t , n tf ) filter coefficients of the adaptive filter such that the minimum There is calculated as the filter coefficient after updating. In the equation (17), * denotes a complex conjugate.
[0156]
[Formula 17]

[0157]
　In this case, the update equation shown in equation (18) in a manner similar to that described above can be obtained.
[0158]
[Equation 18]

[0159]
　In the equation (18), w (n t , n tf ) shows the filter coefficient before updating, w (n t + 1, n tf ) represents the filter coefficient after updating. Further, the μ in the equation (18) represents the step size, X 'is represented by the following formula (19).
[0160]
[Number 19]

[0161]
　In the formula (19), n indicates the order of the spatial frequency, * denotes a complex conjugate. Also, S ' n ref (n t , n tf ) shows the spatial frequency spectrum of the reference signal which is the output of the spatial frequency analysis unit 83, the spatial frequency spectrum S' n ref (n t , n tf ) is , the spatial frequency spectrum S 'in the above-mentioned formula (11) n (n tf is). Further alpha n represents the spatial frequency spectrum of the estimated secondary path.
[0162]
　Thus, for example, the estimated secondary path adding section 84, the spatial frequency spectrum S ' n ref (n t , n tf spatial frequency spectrum α) of the estimated secondary path n so that the calculation for obtaining the product of is performed.
[0163]
　In the adaptive filter coefficient calculation unit 89, the spatial frequency spectrum supplied from the estimated secondary path adding section 84 S ' n ref (n t , n tf ) alpha n , the spatial frequency spectrum of the error signal S' n err (n t , n tf ), and updates the previous filter coefficients w (n t , n tf based on) is calculated equation (18), updated filtering coefficient w (n t + 1, n tf ) is calculated.
[0164]
(Spatial frequency synthesizing unit)
　spatial frequency synthesizing unit 91, in accordance with the shape of the speaker array 93, spatial frequency synthesis spatial frequency spectrum of the loudspeaker drive signal supplied from the adaptive filter unit 90.
[0165]
　For example the order of the spatial frequency is n, the maximum degree of the spatial frequency as N, the spatial frequency spectrum of an output of the adaptive filter section 90 speaker drive signal D ' n (n tf and denoted).
[0166]
　In this case, for example, when the speaker array 93 is annular speaker array performs spatial frequency synthesis by the spatial frequency synthesizing unit 91 to calculate the following equation (20).
[0167]
[Number 20]

[0168]
　In the equation (20) D denotes the vector of the time-frequency spectrum of the loudspeaker drive signal to be output of the spatial frequency synthesizing unit 91, E sp indicates a matrix comprising a circular harmonics. Further, D 'is the spatial frequency spectrum D of the speaker drive signal as an input of the spatial frequency synthesis unit 91' n (n tf indicates a vector of).
[0169]
　That is, represented by the vector D 'is the following formula (21), the matrix E sp is expressed by the following equation (22), the vector D is expressed by the following equation (23).
[0170]
[Number 21]

[0171]
[Equation 22]

[0172]
[Number 23]

[0173]
　Incidentally, n in formula (21) and Equation (23) tf indicates the time-frequency index, in the formula (22) and Equation (23), l denotes the speaker index identifying a speaker that constitutes a speaker array 93 and, l = 0,1,2, ..., is the L-1. Further, L is shows the number of speakers is the number of speakers constituting the speaker array 93. In particular, D in equation (23) (l, n tf ) shows a time-frequency spectrum of the loudspeaker drive signal.
[0174]
　Furthermore, in the equation (22), i denotes a pure imaginary number, n (where, n = -N, -N + 1 , ..., N) denotes the order of the spatial frequency, phi l speaker array speaker index 93 indicates the azimuthal position of the speaker is l. The azimuthal angle phi l azimuth phi location of microphones described above q corresponds to.
[0175]
　Further, for example, when the speaker array 93 are spherical speaker array performs spatial frequency synthesis by the spatial frequency synthesizing unit 91 to calculate the following equation (24).
[0176]
[Number 24]

[0177]
　In the equation (24), D is the formula time frequency spectrum D shown in (23) (l, n tf is a vector consisting of), Y sp represents the matrix of spherical harmonics. Further, D 'has the formula spatial frequency spectrum D shown in (21)' n (n tf is a vector composed of).
[0178]
　Matrix Y consisting of spherical harmonics sp is expressed by the following equation (25).
[0179]
[Number 25]

[0180]
　Incidentally, theta in the formula (25) l and phi l are elevation theta positions of microphones described above q and azimuth phi q corresponding to the elevation theta positions of the speakers of the speaker array 93 l and azimuth phi l indicates and, N and M represents the maximum order of spatial frequency. Further, Y n m (theta l , phi l ) shows the spherical harmonics.
[0181]
　Spatial frequency synthesizing unit 91, the formula (20) and time-frequency spectrum D (l, n of the speaker driving signal obtained by the spatial frequency synthesis shown in equation (24) tf supplying) time to frequency synthesis unit 92.
[0182]
(Time-frequency synthesis unit)
　time-frequency synthesis unit 92, the spatial frequency synthesizing unit 91 is supplied from the time frequency spectrum D (l, n tf use a) with respect to IDFT (Inverse Discrete Fourier Transform) (Inverse Discrete Fourier transform) performed have time-frequency synthesis, speaker drive signal d (l, n is a time signal t to calculate a).
[0183]
　That is, in the time-frequency synthesis, calculation of the following equation (26) takes place.
[0184]
[Number 26]

[0185]
　In the equation (26), n t denotes a time index, M dt denotes the number of samples of IDFT, i denotes the pure imaginary number.
[0186]
　Time frequency synthesizer 92, loudspeaker drive signal d (l, n obtained by time-frequency synthesis t ) was supplied to the speaker array 93, the speaker drive signal d (l, n t to output sound based on).
[0187]

　Next, the operation of the spatial noise control device 71.
[0188]
　That is, the following, a noise canceling process will be described which is performed by the spatial noise control apparatus 71 with reference to the flowchart of FIG.
[0189]
　In step S11, the spatial noise control apparatus 71 performs sound collection with reference microphone array 81. In other words, the reference microphone array 81 picks up ambient sound, and supplies a reference signal obtained as a result the time-frequency analyzer 82.
[0190]
　In step S12, the time-frequency analysis unit 82 performs a time-frequency conversion on the reference signal supplied from the reference microphone array 81, and supplies the time-frequency spectrum of the resulting reference signal to the spatial frequency analyzer 83. For example, in step S12, calculation is performed time-frequency spectrum of the formula (9) described above is calculated.
[0191]
　In step S13, the spatial frequency analysis unit 83 performs a spatial frequency transform on the time-frequency spectrum supplied from the time-frequency analysis unit 82, the resulting estimate the spatial frequency spectrum secondary path adding unit 84 and adaptive It is supplied to the filter unit 90. For example, in step S13, calculation is carried out spatial frequency spectrum of the above-mentioned formula (10) or (15) is calculated.
[0192]
　In step S14, the estimated secondary path adding unit 84 multiplies the spatial frequency spectrum of the estimated secondary path with respect to the spatial frequency spectrum supplied from the spatial frequency analyzer 83, adaptive and the resulting spatial frequency spectrum and it supplies the filter coefficient calculation unit 89. For example, in step S14, the spatial frequency spectrum S 'shown in equation (19) above n ref (n t , n tf ) alpha n is calculated.
[0193]
　In step S15, the spatial noise control apparatus 71 performs sound collection at error microphone array 85. That is, the error microphone array 85, picks up ambient sound, and supplies the error signal obtained as a result the time-frequency analyzer 86.
[0194]
　In step S16, the time-frequency analysis unit 86 performs a time-frequency conversion on the error signal supplied from the error microphone array 85, and supplies the time-frequency spectrum of the resulting error signal to the spatial frequency analyzer 87. For example, in step S16, the calculation similar to that of equation (9) described above are carried out.
[0195]
　In step S17, the spatial frequency analysis unit 87 performs a spatial frequency transform on the time-frequency spectrum supplied from the time-frequency analyzer 86, and supplies the resulting spatial frequency spectrum in the adaptive filter coefficient calculation unit 89 . For example, in step S17, the same calculation is performed with the above Expression (10) or (15).
[0196]
　In step S18, the control area the noise detection unit 88, for example, a camera or a sensor signal which is the output of a sensor, such as the output of the detection microphone, the reference signal, and detects a control area noise like based on the error signal, the supplying a noise detection signal indicating the detection result to the adaptive filter coefficient calculation unit 89.
[0197]
　In step S19, the adaptive filter coefficient calculation unit 89, based on the supplied noise detection signal from the control area the noise detection unit 88 determines whether or not to update the filter coefficients of the adaptive filter. For example, when the noise detection signal is a signal indicating that the control area the noise is not detected, it is determined that updating.
[0198]
　If it is determined to perform the update in step S19, the process proceeds to step S20.
[0199]
　Adaptive filter coefficient calculation unit 89 in step S20 calculates the spatial frequency spectrum of the estimated secondary path adding section 84, the filter coefficients of the adaptive filter based on the spatial frequency spectrum of the spatial frequency analysis unit 87, the filter coefficients to update. For example, in step S20, calculation is carried out filter coefficients of equation (18) described above is updated.
[0200]
　Adaptive filter coefficient calculation unit 89 supplies the filter coefficients obtained after updating the adaptive filter section 90, then the process proceeds to step S21.
[0201]
　In contrast, if it is determined that not updated in step S19, i.e., if the control area the noise is detected in the control area, the processing in step S20 is not performed, the process proceeds to step S21 .
[0202]
　Or it is determined not updated in step S19, or the process of step S20 is performed, step S21 is performed.
[0203]
　That is, in step S21, the adaptive filter unit 90 using the filter coefficient of the adaptive filter which is supplied from the adaptive filter coefficient calculation unit 89 performs filtering processing on the spatial frequency spectrum supplied from the spatial frequency analyzer 83.
[0204]
　Adaptive filter section 90 supplies the spatial frequency spectrum of the loudspeaker drive signal obtained by filtering the spatial frequency synthesizing unit 91.
[0205]
　In step S22, the spatial frequency synthesizing unit 91, the spatial frequency spectrum supplied from the adaptive filter unit 90 and the spatial frequency synthesis, and supplies the time-frequency spectrum of the resulting speaker driving signals time-frequency synthesis unit 92. For example, in step S22, calculation is performed time-frequency spectrum of the above-mentioned formula (20) or formula (24) is calculated.
[0206]
　In step S23, the time-frequency synthesis unit 92 is time-frequency synthesis time frequency spectrum supplied from the spatial frequency synthesizer unit 91 supplies the speaker drive signal is the resulting time signal to the speaker array 93. For example, in step S23, the speaker drive signal is performed calculation of the above equation (26) is calculated.
[0207]
　In step S24, the speaker array 93 outputs a sound based on the speaker drive signal supplied from the time-frequency synthesis unit 92. Thereby, the sounds output from the speaker array 93, the external noise noise canceling region is canceled (reduced).
[0208]
　In step S25, the spatial noise control device 71 determines whether to end the process.
[0209]
　In step S25, if it is determined not to end the unprocessed, the process returns to step S11, the process described above is repeated.
[0210]
　In contrast, if it is determined that the process ends in step S25, the noise canceling process ends.
[0211]
　Spatial noise control device 71 as described above generates a speaker drive signal by filtering processing using the filter coefficient of the adaptive filter, it outputs a sound to cancel the external noise. In this case, spatial noise control device 71 detects the control area noise generated in the control region, and controls the updating of the filter coefficients of the adaptive filter according to the detection result.
[0212]
　Thus, control area noise is detected and suppressed the divergence of the adaptive filter by controlling the updating of the filter coefficients of the adaptive filter in accordance with the detection result, it is possible to improve the noise canceling performance.
[0213]
　Moreover, the spatial noise control device 71, updates and filtering process of the filter coefficients is performed in the spatial frequency domain. In other words, reducing the external noise, that is, the speaker drive signal sounds for canceling produced by the wave field synthesis.
[0214]
　Therefore, the overall noise canceling region, the wavefront of the external noise is canceled (to cancel) sound obtained by wavefront synthesis, it is possible to obtain a high noise canceling performance.
[0215]
　Further, since the update and filtering process of the filter coefficients is performed in the spatial frequency domain, it is possible to reduce the calculation amount by diagonalization of the transfer characteristic. This makes it possible to filter coefficients of the adaptive filter is rapidly converged, improve the noise canceling performance.
[0216]

　In the above, although the case where the present technique is applied to a feedforward ANC system has been described as an example, the feedback type this technology it is of course also possible to apply to the ANC system. The following description the case of application of the present technology Feedback ANC system as an example.
[0217]
　In such a case, the spatial noise control apparatus is configured as shown in FIG. 7, for example. Note that portions corresponding to the case in FIG. 3 in FIG. 7 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
[0218]
　Spatial noise control device 131 shown in FIG. 7, error microphone array 85, time-frequency analysis unit 86, the spatial frequency analysis unit 87, the estimated secondary path adding unit 141, adding unit 142, the estimated secondary path adding unit 143, the control region internal noise detection unit 88, the adaptive filter coefficient calculation unit 89, the adaptive filter section 90 has a spatial frequency synthesizing unit 91, a time-frequency synthesis unit 92 and the speaker array 93,.
[0219]
　The spatial noise control device 131, reference microphone array 81 is not used, the sound is used only error microphone array 85 is picked up.
[0220]
　Further, the spatial frequency spectrum of the error signal obtained by the spatial frequency analyzer 87 is supplied to the adaptive filter coefficient calculation unit 89 and the addition unit 142. Furthermore the spatial frequency spectrum of the loudspeaker drive signal by the adaptive filter section 90 is supplied to a space frequency synthesizing unit 91 and the estimated secondary path adding unit 141.
[0221]
　Estimated secondary path adding unit 141 corresponds to the estimated secondary path adding unit 84 multiplies the spatial frequency spectrum of the estimated secondary path with respect to the spatial frequency spectrum of the loudspeaker drive signal supplied from the adaptive filter unit 90, the the spatial frequency spectrum obtained as a result is supplied to the adder 142.
[0222]
　Adding section 142 adds the spatial frequency spectrum of the error signal supplied from the spatial frequency analyzer 87, and a spatial frequency spectrum supplied from estimated secondary path adding unit 141, estimates the resulting spatial frequency spectrum two It supplies the next path adding unit 143 and the adaptive filter section 90.
[0223]
　Estimated secondary path adding unit 143 corresponds to the estimated secondary path adding unit 84 multiplies the spatial frequency spectrum of the estimated secondary path with respect to the spatial frequency spectrum supplied from the adding unit 142, obtained as a result space supplying the frequency spectrum to the adaptive filter coefficient calculation unit 89.
[0224]
　Adaptive filter coefficient calculation unit 89 according to the supplied noise detection signal from the control area the noise detection unit 88, and the spatial frequency spectrum of the estimated secondary path adding unit 143, the error signal from the spatial frequency analyzer 87 calculating a filter coefficient of the adaptive filter based on the spatial frequency spectrum, and supplies to the adaptive filter unit 90.
[0225]
　Adaptive filter 90 uses the filter coefficient of the adaptive filter which is supplied from the adaptive filter coefficient calculation unit 89 performs filtering processing on the spatial frequency spectrum supplied from the adding unit 142, the spatial frequency spectrum of the loudspeaker drive signal to generate.
[0226]
　Since the spatial noise control device 131 when it is a feedback type, see the microphone array 81 is not used, the control region is a region formed by the error microphone array 85 as shown in FIG. 8, for example, that error microphone is an area surrounded by the array 85. Note that portions corresponding to the case in FIG. 7 in FIG. 8 are denoted by identical reference numerals, and description thereof will be omitted as appropriate.
[0227]
　In the example shown in FIG. 8, the error microphone array 85 are arranged in the region surrounded by the speakers of the speaker array 93.
[0228]
　The spatial noise control device 131, the inner portion of the error microphone array 85 which hatch has been applied, that is, a range of a portion surrounded by each microphone is a control region, noise generated in the control region are detected. Also, the noise canceling region, as in the spatial noise control device 71, a region surrounded by the speaker array 93 is a noise canceling region.
[0229]

　Next, the operation of the spatial noise control device 131.
[0230]
　That is, the following, a noise canceling process will be described which is performed by the spatial noise control device 131 with reference to the flowchart of FIG.
[0231]
　When the noise canceling process is started, the processing of steps S61 to step S63 is performed, since these processes are the same as steps S15 to step S17 in FIG. 6, a description thereof will be omitted. However, in step S63, the spatial frequency spectrum of the error signal obtained by the spatial frequency transformation from the spatial frequency analyzer 87, is supplied to the adaptive filter coefficient calculation unit 89 and the addition unit 142.
[0232]
　In step S64, the estimated secondary path adding unit 141 multiplies the spatial frequency spectrum of the estimated secondary path with respect to the spatial frequency spectrum of the supplied speaker drive signal from the adaptive filter unit 90, the resulting spatial frequency supplying the spectrum to the adder 142.
[0233]
　In step S65, the adder unit 142 performs addition processing. That is, the adder unit 142 adds the spatial frequency spectrum supplied from the spatial frequency analyzer 87, and a spatial frequency spectrum supplied from estimated secondary path adding unit 141, the two resulting spatial frequency spectrum estimation order and it supplies the path adding unit 143 and the adaptive filter section 90.
[0234]
　In step S66, the estimated secondary path adding unit 143, the spatial frequency spectrum by multiplying the resulting spatial frequency spectrum adaptive filter coefficients of the estimated secondary path with respect to the supplied spatial frequency spectrum from the adding unit 142 supplied to the calculation unit 89.
[0235]
　When the process of step S66 is executed, then the processing in steps S67 to step S74 is performed by the noise canceling process ends, since these processes are the same as those in step S18 to step S25 in FIG. 6 , and a description thereof will be omitted.
[0236]
　However, in step S69, the adaptive filter coefficient calculation unit 89, and the spatial frequency spectrum of the estimated secondary path adding unit 143, and updates the filter coefficient of the adaptive filter based on the spatial frequency spectrum of the spatial frequency analyzer 87 .
[0237]
　Further, in step S70, the adaptive filter unit 90, using the filter coefficients of the adaptive filter which is supplied from the adaptive filter coefficient calculating unit 89 performs a filtering process on the supplied spatial frequency spectrum from the adding unit 142, a speaker calculating a spatial frequency spectrum of the driving signal. Further, the adaptive filter unit 90 supplies the spatial frequency spectrum of the loudspeaker drive signal to the spatial frequency synthesizing unit 91 and the estimated secondary path adding unit 141.
[0238]
　Spatial noise control device 131 as described above generates a speaker drive signal by filtering processing using the filter coefficient of the adaptive filter, it outputs a sound to cancel the external noise. In this case, spatial noise control device 131 detects a control area noise generated in the control region, and controls the updating of the filter coefficients of the adaptive filter according to the detection result.
[0239]
　Thus, control area noise is detected and suppressed the divergence of the adaptive filter by controlling the updating of the filter coefficients of the adaptive filter in accordance with the detection result, it is possible to improve the noise canceling performance.
[0240]

　Now, the spatial noise control device 71 and the spatial noise control device 131 described above, it is conceivable to apply such as a vehicle and hospitals.
[0241]
　That is, for example, a speaker array of a large number of speakers in the vehicle interior of the vehicle such as a passenger car, a microphone array comprising a plurality of microphones are placed.
[0242]
　And engine noise or road noise coming from the control area outside this time, if reduced by employing the present technology (canceled), it is possible to keep the vehicle gently. In particular, in this case, even when the vehicle in a controlled area noise is generated, it is possible to suppress the reduction of the noise canceling performance using the present technology.
[0243]
　In addition, the hospital there is a shared room that hospitalized patients of more than one person to live in the same room. In such a case, although the visibility is shielding curtain, sound and sound around the other patients will be heard for each hospitalized patient. Therefore, was placed on the spatial noise control device according to the present technique with stand, by enclosing the predetermined region by the microphone array and the speaker array, it can be canceled sound from the control area outside. Thus, it is possible to secure a quiet space for each hospitalized patient. Further, by installing a spatial noise control apparatus according to the present technology each bed portion of all patients, can be like the voice of each other is suppressed to one another, also be utilized to protect the privacy.
[0244]

　In the above, reference microphone array 81 and error microphone array 85, although the speaker array 93 has been described as a specific example, a case is spherical or annular, these reference microphone array 81 and error microphone array 85, the shape of the speaker array 93 including a linear shape, and may be any shape.
[0245]
　For example if the reference microphone array, error microphone arrays, and the loudspeaker array is a linear shape, their arrangement of the microphone array and the speaker array is as shown in FIG. 10.
[0246]
　In the example shown in FIG. 10, the reference microphone array 171 is a linear microphone array, a speaker array 172 is a linear loudspeaker array error microphone array 173 and a linear microphone array, the direction perpendicular to the direction in which their microphones and speakers are aligned It is arranged in.
[0247]
　That is, in the rear, ie Figure of the speaker array 172 is arranged is referred to above microphone array 171, the front of the speaker array 172, i.e. in the figure, the error microphone array 173 is disposed on the lower side. Here the radial direction of the sound by the speaker array 172 in the figure is the lower.
[0248]
　For example, in spatial noise control apparatus 71 of the feedforward type, the reference microphone array 81, error microphone array 85, and in place of the speaker array 93, the reference microphone array 171, error microphone array 173 and the speaker array 172, it is used.
[0249]
　In this case, in the drawing than the reference microphone array 171, a rectangular region R11 of the lower side is the control area, in the drawing than the speaker array 172 of this region R11, the lower side, that the error microphone array 173 side region There is a noise canceling region.
[0250]
　Further, for example, may be arranged side by side linear microphone array or linear loudspeaker array in a rectangular frame shape as shown in FIG. 11.
[0251]
　In the example shown in FIG. 11, in a region surrounded by a rectangular frame shape of the reference microphone array 201 comprised of four straight microphone array, the speaker array 202 of rectangular frame shape composed of four straight speaker array is arranged. Further, the error microphone array 203 of rectangular frame shape composed of four straight microphone array within the region surrounded by the speaker array 202 is arranged. In this example, for example, in spatial noise control apparatus 71 of the feedforward type, the reference microphone array 81, instead of the error microphone array 85 and the speaker array 93, the reference microphone array 201, error microphone array 203 and the speaker array 202, is used It will be used.
[0252]
　In this case, regions R21 surrounded by reference microphone array 201 is set to the control region, the region surrounded by the speaker array 202 is a noise canceling region.
[0253]
　Similarly, if the linear microphone array and a linear loudspeaker array is used in the spatial noise control device 131 of the feedback type, the spatial noise controller 131, for example, the speaker array 172 instead of the speaker array 93, as shown in FIG. 12 is used , error microphone array 173 is used instead of the error microphone array 85. Note that portions corresponding to the case in FIG. 10 in FIG. 12 are denoted by identical reference numerals, and a description thereof will be omitted.
[0254]
　In the example shown in FIG. 12, in FIG than the error microphone array 173, a rectangular region R31 of the lower side is the control area, in the drawing than the speaker array 172, the lower side, that the rectangular region of the error microphone array 173 side There is a noise canceling region.
[0255]
　Furthermore, if the microphone array and the speaker array of the rectangular frame shape is used, the spatial noise controller 131, for example, the speaker array 202 instead of the speaker array 93, as shown in FIG. 13 using the spatial noise control device 131 of Feedback is, error microphone array 203 is used instead of the error microphone array 85. Note that portions corresponding to the case in FIG. 11 in FIG. 13 are given the same reference numerals, and a description thereof will be omitted.
[0256]
　In the example shown in FIG. 13, a rectangular region R41 surrounded by error microphone array 203 is a control region, a rectangular region surrounded by the speaker array 202 is a noise canceling region.
[0257]
　As described above, if a reference microphone array and error microphone array, a speaker array conducts the above-described process, even if a linear shape or a rectangular frame shape, the control area noise control area is detected, the adaptive filter coefficients of the filter so as not updated, thereby improving the noise canceling performance.
[0258]

　In addition, instead of each of the microphones constituting the reference microphone array and error microphone array may be used spherical microphone array or cyclic microphone array as shown in FIG. 14 for example. In FIG. 14, portions corresponding to the case in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
[0259]
　In the example shown in FIG. 14, the speaker array 93 in a region surrounded by reference microphone array 231 is arranged, error microphone array 232 in a region surrounded by the speaker array 93 is disposed. Also, the reference microphone array 231 corresponds to a reference microphone array 81, error microphone array 232 corresponds to the error microphone array 85.
[0260]
　In this example, the reference microphone array 231 is composed of a plurality of microphone arrays 241-1 through microphone array 241-8. In the following description, when it is necessary to distinguish the microphone array 241-1 to microphone arrays 241-8, simply referred to as the microphone array 241.
[0261]
　Each microphone array 241 is a spherical microphone array or cyclic microphone array obtained by arranging a plurality of microphones in spherical or toroidal. Here, one annular microphone array a plurality of microphone array 241 by placing side by side annularly configured, the annular microphone array is a reference microphone array 231.
[0262]
　Similarly, error microphone array 232 is composed of a plurality of microphone arrays 242-1 through microphone array 242-4. In the following description, when it is necessary to distinguish the microphone array 242-1 to microphone arrays 242-4, simply referred to as the microphone array 242.
[0263]
　Each microphone array 242 is a spherical microphone array or cyclic microphone array obtained by arranging a plurality of microphones in spherical or toroidal. Here, one annular microphone array a plurality of microphone array 242 by placing side by side annularly configured, the annular microphone array is the error microphone array 232.
[0264]
　In this example, the spatial noise controller 71, the reference microphone array 231 is used in place of the reference microphone array 81, error microphone array 232 in place of the error microphone array 85 is used.
[0265]
　Incidentally, the reference microphone array 231 may be a spherical microphone array of the microphone array 241, error microphone array 232 similarly may be spherical microphone array of the microphone array 242.
[0266]
　See microphone array 231 and error microphone array 232 With such a configuration, it is possible to suppress the leakage of the control area the noise reference microphone array 231 from the inside of the control region. Further, it is possible to suppress leakage of unnecessary sounds such as the reference sound sneaking into the microphone array 231 of the sound for the noise canceling output from the speaker array 93.
[0267]
　The reference microphone array 231 and error microphone array 232 by constituting the microphone array 241 and the microphone array 242 is a circular microphone array or spherical microphone array, it is possible to give a directivity to their respective microphone array 241 and the microphone arrays 242 so as to. Thus, for example, control area outside the directivity that controls the microphone array 241 and the microphone array 242 so as to face, it is possible to further improve the noise canceling performance.
[0268]
　It is difficult to have a practically complete directivity of what it is possible to have a directivity and using cyclic microphone array or spherical microphone array, leakage of directional control alone is unwanted sounds the can not be completely prevented. However, by using a technique for constituting a reference microphone array and error microphone array of a plurality of microphone arrays in combination with spatial noise control apparatus described above, it is possible to further improve the noise canceling performance.
[0269]
　It is to be noted that the directional control of the microphone array, for example, "Meyer, Jens, and Gary Elko." A highly scalable spherical microphone array based on an orthonormal decomposition of the soundfield. "Acoustics, Speech, and Signal Processing (ICASSP), 2002 IEEE International Conference on. Vol. 2. IEEE, has been described in detail, such as in 2002. ".
[0270]

　In place of the each of the speakers constituting the speaker array to output the sound for noise canceling, for example also possible to use a spherical speaker array and cyclic loudspeaker array as shown in FIG. 15 good. In FIG. 15, portions corresponding to the case in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
[0271]
　In the example shown in FIG. 15, the speaker array 271 is arranged in a region surrounded by reference microphone array 81, error microphone array 85 are arranged in a region surrounded by the speaker array 271. The speaker array 271 corresponds to the speaker array 93.
[0272]
　In this example, the speaker array 271 is composed of a plurality of speaker array 281-1 to the speaker array 281 - 4. In the following description, when it is necessary to distinguish the speaker array 281-1 to the speaker array 281 - 4, simply referred to as the speaker array 281.
[0273]
　Each speaker array 281 is a spherical speaker array or cyclic loudspeaker array obtained by arranging a plurality of speakers in spherical or toroidal. Here, one annular speaker array a plurality of the speaker array 281 by placing side by side annularly configured, the annular speaker array is the speaker array 271. In this example, the spatial noise control device 71, the speaker array 271 is used instead of the speaker array 93.
[0274]
　Incidentally, the speaker array 271 may be a spherical speaker array of the speaker array 281.
[0275]
　By configuring the speaker array 271 of a plurality of speaker array 281, to play the sound only surrounded by noise canceling region by the speaker array 271, to suppress the leakage of sound to the noise canceling area outside can.
[0276]
　For example output by arranged loudspeakers to face the inside of the noise canceling region constituting the speaker array 281, a sound goes around to the reference microphone array 81, in the noise canceling region outside noise canceling constituting the speaker array 281 it can be canceled by the sound output by the arranged speakers to face the outer ring region. Thus, by using the loudspeaker array 271, it is possible to suppress the diffraction of the reference microphone array 81 of the sound output from the speaker array 271, it is possible to improve the noise canceling performance.
[0277]
　For example, if the annular speaker array and the spherical speaker array arranging a plurality a speaker array, the in practice of what is possible to suppress the diffraction of sound to the outside of the region surrounded by the speaker array only that wraparound full Nioto it is difficult to prevent. However, by using in combination with the spatial noise control apparatus described above a technique for constituting a speaker array of a plurality of speaker array, it is possible to further improve the noise canceling performance.
[0278]
　Incidentally, by arranging a plurality of speaker array constitute one of the speaker array, for a technique for suppressing echo sound, for example, "Samarasinghe, Prasanga N., et al." 3D soundfield reproduction using higher order loudspeakers. "2013 IEEE International Conference on Acoustics, Speech and Signal Processing. IEEE, has been described in detail, such as in 2013. ".
[0279]

　In addition, for example, a technique that one microphone array arranging a plurality of annular microphone array or spherical microphone array as shown in FIG. 16, a technique for a single speaker array by arranging a plurality of annular speaker array and spherical speaker array it may be used in combination. Note that portions corresponding to the case in FIG. 14 or 15 in FIG. 16 are denoted by identical reference numerals, and description thereof will be omitted as appropriate.
[0280]
　In this example, the reference microphone array 81 in the spatial noise controller 71, error microphone array 85, and in place of the speaker array 93, the reference microphone array 231, the error microphone array 232 and the speaker array 271, is used.
[0281]
　In the example shown in FIG. 16, the speaker array 271 is arranged in a region surrounded by reference microphone array 231, error microphone array 232 in a region surrounded by the speaker array 271 is arranged.
[0282]
　In the example described with reference to FIGS. 14 to 16, a technique that constitutes one of the microphone array and the speaker array with spherical or annular microphone array and the speaker array, the feedforward spatial noise control device It has been described a case where to apply. However, a technique that constitutes one of the microphone array and the speaker array using such spherical or annular microphone array and the speaker array may also be applied to a feedback type spatial noise control device.
[0283]

　In addition, for example in the control area the noise detection unit 88 may be configured to detect a control region within the noise based on a reference signal obtained by sound pickup by the reference microphone array.
[0284]
　In such a case, for example, reference microphone array is configured as shown in FIG. 17. Note that portions corresponding to the case in FIG. 3 in FIG. 17 are denoted by identical reference numerals, and description thereof will be omitted as appropriate.
[0285]
　In the example of FIG. 17, reference microphone array 311 in place of the reference microphone array 81 in the spatial noise control device 71 is used. The speaker array 93 is disposed in a region surrounded by reference microphone array 311 is disposed an error microphone array 85 in a region surrounded by the speaker array 93.
[0286]
　Referring microphone array 311 includes a microphone array 321-1 cyclic microphone array or spherical microphone array, and a microphone array 321-2 Metropolitan cyclic microphone array or spherical microphone array.
[0287]
　In particular, where the radius of the microphone array 321-1, since smaller than the radius of the microphone array 321-2, side microphone arrays 321-1 close against microphone array 321-2, the more the speaker array 93 It is arranged at the position.
[0288]
　That is, the distance from the center position of the control region to the microphone array 321-1, the distance from the center position of the control region to the microphone array 321-2 is different.
[0289]
　Therefore, for example, a control area noise generated in the control region picked up by reference microphone array 311, the reference signal a sound pressure of a reference signal obtained by the microphone array 321-1, obtained by the microphone array 321 - It is larger than the sound pressure of.
[0290]
　In contrast, when picked up by reference microphone array 311 external noise propagated through to the control area from outside the control area, than the sound pressure of the reference signal obtained by the microphone array 321-1, the microphone array 321 the sound pressure of a reference signal obtained -2 ​​increases.
[0291]
　Therefore, if supplying a reference signal obtained by the reference microphone array 311 to the control area the noise detection unit 88, control area the noise detection unit 88 and the sound pressure of a reference signal obtained by the microphone array 321-1, a microphone by comparing the sound pressure of a reference signal obtained by the array 321-2, it is possible to detect a control region within the noise.
[0292]
　Incidentally, as in the reference microphone array 311 is constituted from the two or more different microphone array distance from the center of the control area error microphone array 85, is supplied from the error microphone array 85 in the control area the noise detection unit 88 it may be detected to control area noise on the basis of the error signal.
[0293]
　Further, for example, the See also the microphone array 231 and the error microphone array 232 shown in FIG. 16, as a microphone which constitutes their microphone array, there are two or more microphones at different distances from the center of the control region. Therefore, even by using the reference signal and the error signal obtained by the reference microphone array 231 and the error microphone array 232, in the same manner as in the reference microphone array 311, it is possible to detect a control region within the noise.
[0294]

　In addition, also in the spatial noise control device 131, it is possible to detect a control region within the noise based on the error signal obtained by sound pickup by the error microphone array.
[0295]
　In such a case, for example, error microphone array is configured as shown in FIG. 18. Note that portions corresponding to the case in FIG. 7 in FIG. 18 are denoted by identical reference numerals, and description thereof will be omitted as appropriate.
[0296]
　In the example of FIG. 18, error microphone array 351 is used in place of the error microphone array 85 in the spatial noise control device 131. The error microphone array 351 is disposed in a region surrounded by the speaker array 93.
[0297]
　Error microphone array 351, a microphone array 361-1 cyclic microphone array or spherical microphone array, and a microphone array 361-2 Metropolitan cyclic microphone array or spherical microphone array.
[0298]
　In particular, where the radius of the microphone array 361-1 is because it is smaller than the radius of the microphone array 361-2, side microphone array 361-2 is close against the microphone array 361-1, the more the speaker array 93 It is arranged at the position.
[0299]
　That is, the distance from the center position of the control region to the microphone array 361-1, the distance from the center position of the control region to the microphone array 361-2 is different.
[0300]
　Therefore, similarly to the case described with reference to FIG. 17, comparing the sound pressure of the error signal obtained by the microphone array 361-1, and a sound pressure of the error signal obtained by the microphone array 361-2 Accordingly, it is possible to detect a control region within the noise.
[0301]
　Therefore, the error signal obtained by the error microphone array 351 in the example are supplied to the control area the noise detection unit 88, control area the noise detection unit 88 and the sound pressure of the error signal obtained by the microphone array 361-1 , by comparing the sound pressure of the error signal obtained by the microphone array 361-2, detects a control area noise.
[0302]

　The series of processes described above can be executed by hardware or can be executed by software. When executing the series of processing by software, a program constituting the software is installed into a computer. Here, the computer includes a computer incorporated in dedicated hardware, by installing various programs, which can execute various functions include, for example, such as a general-purpose computer.
[0303]
　Figure 19 is a block diagram showing a configuration example of hardware of a computer that executes the series of processes described above.
[0304]
　In the computer, CPU (Central Processing Unit) 501, ROM (Read Only Memory) 502, RAM (Random Access Memory) 503 are connected to each other via a bus 504.
[0305]
　The bus 504 is further output interface 505 is connected. Output interface 505, an input unit 506, output unit 507, recording unit 508, a communication unit 509, and a drive 510 are connected.
[0306]
　Input unit 506 includes a keyboard, a mouse, a microphone array, consisting of an imaging device. The output unit 507 includes a display and a speaker array. Recording unit 508, a hard disk and a nonvolatile memory. Communication unit 509 including a network interface. Drive 510 drives a magnetic disk, an optical disk, a magneto-optical disk, or a removable recording medium 511 such as a semiconductor memory.
[0307]
　Series In the computer configured as described above, CPU 501 is, for example, a program recorded in the recording unit 508 via the input-output interface 505 and the bus 504 and executes the loaded into RAM 503, the above-mentioned processing of is performed.
[0308]
　Program computer (CPU 501) is executed, for example, can be provided by being recorded in a removable recording medium 511 as a package medium or the like. Further, the program may be provided via a local area network, the Internet, or digital satellite broadcasting, a wired or wireless transmission medium.
[0309]
　In the computer, by mounting the removable recording medium 511 into the drive 510, it can be through the input-output interface 505, installed in the recording unit 508. The program via a wired or wireless transmission medium and received by the communication unit 509, can be installed in the recording unit 508. Alternatively, the program may be in the ROM502 and the recording unit 508 installed in advance.
[0310]
　The program which the computer executes may be a program in which processes are performed in time series in the order described herein, at a necessary timing such as when the parallel or call was made processing may be a program to be carried out.
[0311]
　Further, embodiments of the present technology is not limited to the embodiments described above, but various modifications are possible without departing from the scope of the present disclosure.
[0312]
　For example, the present technology, sharing one function by a plurality of devices via a network, it is possible to adopt a configuration of cloud computing which processes jointly.
[0313]
　Further, each step described in the above flowcharts may be executed by one device, it can be performed by allocating a plurality of apparatuses.
[0314]
　Further, when a plurality of processes are included in one step, the plurality of processes included in the one step may be executed by one device, it can be performed by allocating a plurality of apparatuses.
[0315]
　The effects described herein are not intended to be limited to a merely illustrative, there may be other effects.
[0316]
　Additionally, the present technology may also be configured as follows.
[0317]
(1)
　and a noise detector for detecting the control area noise generated in the control region formed by the microphone array,
　by the speaker array in order to reduce the external noise to the noise canceling region formed by the speaker array and a control unit for the updating of the filter coefficients of the adaptive filter used to generate a signal of the outputted output sound is controlled based on the control area the noise of the detection result
　signal processing apparatus comprising a.
(2)
　a signal obtained by sound pickup by the microphone array further comprises an adaptive filter section for generating a signal of the output sound based on said filter coefficient
　signal processing apparatus according to (1).
(3)
　the adaptive filter section, in the spatial frequency domain, the signal obtained by sound pickup by the microphone array performs filtering processing based on said filter coefficients, generates a signal of the output sound
　according to (2) signal processing device.
(4)
　wherein, when said said control region noise by the noise detection unit is detected, the updating of the filter coefficients so as not performed
　according to any one of (1) to (3) signal processing device.
(5)
　the noise detection unit, on the basis of the signal obtained by sound pickup by the microphone array to detect the control area noise
　(1) to the signal processing apparatus according to any one of (4).
(6)
　the noise detection unit constituting the microphone array, on the basis of the respective signals obtained by sound pickup by each of the plurality of microphone array which distance is different from the center position of the control area, the control detecting a region noise
　signal processing apparatus according to (5).
(7)
　the noise detection unit, a signal obtained by sound pickup by the microphone array, the signal distance from the center position of the control area is obtained by sound pickup by different other microphone array and the microphone array based on the bets, detecting the control area the noise
　signal processing apparatus according to (5).
(8)
　the noise detection unit, based on a signal obtained by sound pickup by detecting microphone disposed in the control region, for detecting the control area noise
　either (1) to (4) the signal processing apparatus according to an item.
(9)
　The microphone array is obtained by arranging a plurality of microphone array in a predetermined shape
　signal processing apparatus according to any one of (1) to (8).
(10)
　the loudspeaker array is obtained by arranging a plurality of the speaker array into a predetermined shape
　(1) to the signal processing apparatus according to any one of (9).
(11)
　said control region, wherein a region formed by the reference microphone array or error microphone array as the microphone array
　signal processing apparatus according to any one of (1) to (10).
(12)
　detecting the control area noise generated in the control region formed by the microphone array,
　output by the speaker array in order to reduce the external noise to the noise canceling region formed by the speaker array outputs the updating of the filter coefficients of the adaptive filter used to generate the sound signal is controlled on the basis of the control area noise of the detection result
　signal processing method comprising the steps.
(13)
　detecting the control area noise generated in the control region formed by the microphone array,
　an output that is output by the speaker array in order to reduce the external noise to the noise canceling region formed by the speaker array the updating of the filter coefficients of the adaptive filter used to generate the sound signal is controlled on the basis of the control area the noise detection result
　program for executing the processing including a step in the computer.
DESCRIPTION OF SYMBOLS
[0318]
　71 spatial noise control device, 81 the reference microphone array, 85 error microphone array, 88 control area noise detecting unit, 89 an adaptive filter coefficient calculation unit, 90 an adaptive filter section, 93 the speaker array

The scope of the claims
[Requested item 1]A noise detector for detecting the control area noise generated in the control region formed by the microphone array,
　output by the speaker array in order to reduce the external noise to the noise canceling region formed by the speaker array and a control unit for the updating of the filter coefficients of the adaptive filter used for generating the signal of the output sound is controlled based on the control area the noise of the detection result
　signal processing apparatus comprising a.
[Requested item 2]
　Wherein a signal obtained by sound pickup by the microphone array further comprises an adaptive filter section for generating a signal of the output sound based on said filter coefficient
　signal processing apparatus according to claim 1.
[Requested item 3]
　The adaptive filter section, in the spatial frequency domain, wherein performs filtering processing obtained signal based on said filter coefficients by sound pickup by the microphone array, generates a signal of the output sound
　signal processing according to claim 2 apparatus.
[Requested item 4]
　Wherein, when the control region noise by the noise detecting unit is detected, so that updating of the filter coefficients is not performed
　signal processing apparatus according to claim 1.
[Requested item 5]
　Wherein the noise detecting unit, on the basis of the signal obtained by sound pickup by the microphone array to detect the control area the noise
　signal processing apparatus according to claim 1.
[Requested item 6]
　The noise detection unit constitutes the microphone array, respectively based on the respective signal obtained by sound pickup by the different distances from each other a plurality of microphone array from the center position of the control area, the control area noise detecting a
　signal processing apparatus according to claim 5.
[Requested item 7]
　The noise detection unit, a signal obtained by sound pickup by the microphone array, based on a signal obtained by sound pickup by other different microphone arrays and distance the microphone array from the center position of the control region Te, detecting the control area the noise
　signal processing apparatus according to claim 5.
[Requested item 8]
　The noise detecting unit, based on a signal obtained by sound pickup by detecting microphone disposed in the control region, for detecting the control area the noise
　signal processing apparatus according to claim 1.
[Requested item 9]
　The microphone array is obtained by arranging a plurality of microphone array in a predetermined shape
　signal processing apparatus according to claim 1.
[Requested item 10]
　The speaker array is obtained by arranging a plurality of the speaker array into a predetermined shape
　signal processing apparatus according to claim 1.
[Requested item 11]
　The control region is a region formed by reference microphone array or error microphone array as the microphone array
　signal processing apparatus according to claim 1.
[Requested item 12]
　Detecting the control area noise generated in the control region formed by the microphone array,
　the signal of the output sound output by the speaker array in order to reduce the external noise to the noise canceling region formed by the speaker array the updating of the filter coefficients of the adaptive filter is controlled based on the control area the noise detection result used in the generation of the
　signal processing method comprising the steps.
[Requested item 13]
　Detecting the control area noise generated in the control region formed by the microphone array,
　the signal of the output sound output by the speaker array in order to reduce the external noise to the noise canceling region formed by the speaker array the updating of the filter coefficients of the adaptive filter used in generating, controlled based on the control area the noise of the detection result of the
　program for executing the processing including a step in the computer