JP2015213249A - Sound field controller, sound field control system, and sound field control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control a sound field so that important sound information is audible independently in each region in a closed space.SOLUTION: A sound field controller 100 for controlling, in a closed space including a plurality of speakers 300, a sound field in the closed space formed by a plurality of pieces of input sound information comprises: an acoustic signal generation unit 103 for generating, for each of the plurality of pieces of sound information, a plurality of acoustic signals through a filter having a filter factor according to a transmission target region for each sound information; a signal summation unit 104 for summing up the plurality of acoustic signals; and a sound output unit 105 for supplying the summed acoustic signal to the plurality of speakers 300. The filter factor is calculated on the basis of a transfer matrix from the plurality of speakers 300 to a plurality of regions in the closed space and target sound fields in the plurality of regions.

Description

  The present invention relates to a sound field control device, a sound field control system, and a sound field control method for controlling a sound field in a closed space such as a passenger compartment of an automobile.

  Which sound information is important when multiple pieces of sound information are mixed depends on the purpose of the activity.

  For example, when music by audio equipment and voice guidance by car navigation coexist in the interior of a car, it is preferable that the voice guidance by car navigation is preferentially heard at the driver's seat.

  To make it easier to hear the most important sound information in an environment where multiple sound information is mixed, for example, when voice guidance and music are mixed, the voice guidance can be heard with priority over the music. Thus, an invention for adjusting the sound field characteristics and the output volume has been proposed (see Patent Document 1).

JP 2005-167975 A

  Sound information desired to be preferentially heard varies depending on the region in the interior of a car. For example, as described above, it is preferable that voice guidance by car navigation can be heard preferentially in the driver's seat, and music can be listened preferentially in the rear seat.

  The invention proposed in Patent Document 1 can preferentially hear the voice guidance by car navigation in the driver's seat. However, in order to adjust the sound field characteristics and output sound for the entire passenger compartment of a car, if the voice guidance by car navigation is preferentially heard in the driver's seat, the voice guidance by car navigation is also given priority in the rear seat. I was able to hear it.

  An object of the present invention made in view of such points is a sound field control device and a sound field control capable of controlling a sound field so that important sound information can be heard independently for each region in a closed space. A system and a sound field control method are provided.

  In order to solve the above problems, a sound field control device according to the present invention is a sound field control device for controlling a sound field in a closed space by a plurality of sound information inputted in a closed space having a plurality of speakers. Adding to each of the plurality of sound information an acoustic signal generation unit that generates a plurality of acoustic signals through a filter having a filter coefficient corresponding to a transmission target region of each of the sound information, and the plurality of acoustic signals A signal adding unit, and an acoustic output unit that supplies the added acoustic signals to the plurality of speakers, wherein the filter coefficient is a transfer matrix from the plurality of speakers to a plurality of regions in the closed space; It is calculated based on the target sound field in the plurality of regions.

  In the sound field control apparatus according to the present invention, it is preferable that the filter coefficient is calculated as a solution to an optimization problem related to the transfer matrix and the target sound field.

  In the sound field control apparatus according to the present invention, it is preferable that the solution of the optimization problem includes a regularization coefficient β, and the filter coefficient has a different value according to the regularization coefficient β.

ただし、式（１）において、Ａ_Fは最適化問題の解を示し、Ｇは伝達行列を示し、βは正則化係数を示し、Ｉは単位行列を示し、Ｈ_targetは目標音場を示す。 In the sound field control apparatus according to the present invention, it is preferable that the solution of the optimization problem is given by the following equation (1).

In Equation (1), A _F represents the solution of the optimization problem, G represents the transfer matrix, β represents the regularization coefficient, I represents the unit matrix, and H _target represents the target sound field.

ただし、式（２）において、ｆは周波数を示し、α及びｂは、α＞０、ｂ＞０となる数を示す。 In the sound field control apparatus according to the present invention, the regularization coefficient β is preferably given by the following equation (2).

However, in Formula (2), f shows a frequency and (alpha) and b show the number used as (alpha)> 0 and b> 0.

  In the sound field control apparatus according to the present invention, it is preferable that b = 1/2.

  The sound field control apparatus according to the present invention preferably further includes a setting unit for setting the regularization coefficient β.

  In the sound field control device according to the present invention, it is preferable that the setting unit sets the volumes of the plurality of sound information in the plurality of regions, respectively.

  In the sound field control device according to the present invention, it is preferable that the setting unit sets a sound image position in each of the plurality of regions.

  In order to solve the above-described problem, a sound field control system according to the present invention includes a sound field control device that controls a sound field in a closed space based on a plurality of pieces of sound information input, and a plurality of speakers. A sound field control system comprising: the sound field control device, for each of the plurality of sound information, passing a plurality of acoustic signals through a filter having a filter coefficient corresponding to a region to which the sound information is transmitted. An acoustic signal generation unit for generating, a signal addition unit for adding the plurality of acoustic signals, and an acoustic output unit for supplying the added acoustic signals to the plurality of speakers. The calculation is based on a transfer matrix from a speaker to a plurality of regions in the closed space and a target sound field in the plurality of regions.

  Further, in the sound field control system according to the present invention, the plurality of speakers are speakers selected by a speaker arrangement selection device, and the speaker arrangement selection device has an initial arrangement number of speakers larger than the number of the plurality of speakers. Is installed, the singular value decomposition is performed on the transfer matrix from the speaker having the initial arrangement number to the plurality of regions in the closed space, and the initial arrangement number is obtained from the orthogonal matrix obtained by the singular value decomposition. Preferably, the plurality of speakers are selected by calculating an EfI (Effective Independence) value and selecting a desired number of speakers having higher EfI values from the initial number of EfI values.

  In order to solve the above problems, a sound field control method according to the present invention is a sound field control method for controlling a sound field in a closed space by a plurality of input sound information in a closed space having a plurality of speakers. A step of generating a plurality of sound signals through a filter having a filter coefficient corresponding to a region to which each sound information is transmitted, and a step of adding the plurality of sound signals to each of the plurality of sound information And supplying the added acoustic signals to the plurality of speakers, wherein the filter coefficient is a transfer matrix from the plurality of speakers to a plurality of regions in the closed space, and in the plurality of regions. It is calculated based on the target sound field.

  According to the present invention, there is provided a sound field control device, a sound field control system, and a sound field control method capable of controlling a sound field so that important sound information can be heard independently for each region in a closed space. Can be provided.

It is a figure showing the schematic structure of the sound field control system concerning one embodiment of the present invention. It is a figure which shows an example of arrangement | positioning of the sound source position and measurement position in the vehicle interior of a motor vehicle. It is a conceptual diagram which shows a mode that the sound field concentrated on the area | region A and the sound field concentrated on the area | region B are synthesize | combined. It is a figure which shows the mode of a sound field separation in the case of (beta) = 1 / f. It is a figure which shows the mode of sound field separation in the case of (beta) = 40 / √f. It is a figure which shows an example of (beta) dependence ((alpha) dependence) of the difference of a sound pressure level. It is a figure which shows an example of (beta) dependence of condition numbers. It is a figure which shows an example of a volume operation interface. It is a figure which shows an example of a sound image operation interface. It is a figure which shows schematic structure of the speaker arrangement | positioning selection apparatus which concerns on one Embodiment of this invention. It is a figure which shows an example which has arrange | positioned 64 speakers in the vehicle interior of a motor vehicle. It is a figure which shows an example of a mode that 24 speakers with high linear independence are selected from 64 speakers. It is a figure which shows an example of a mode that a condition number falls by selecting a speaker with high linear independence.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a schematic configuration of a sound field control system 10 according to an embodiment of the present invention. The sound field control system 10 is a system that transmits independent sound information in multiple areas, for example, in a closed space such as the interior of a car. Here, “multi-region” means a plurality of regions such as a driver's seat and a rear seat. The “sound information” is, for example, music or voice guidance for car navigation. For example, the sound field control system 10 controls the sound field independently for each region so that voice guidance can be easily heard in the driver's seat and music can be easily heard in the rear seat.

  The sound field control system 10 includes a sound field control device 100 that controls a sound field, a signal reproduction device 200 that outputs various types of sound information, and a plurality of speakers 300.

  The sound field control device 100 causes the sound information to be reproduced from the plurality of speakers 300 by independently controlling the sound field for each region of the plurality of sound information input from the signal reproduction device 200. Details of the sound field control apparatus 100 will be described later.

  For example, the signal reproduction device 200 provides the sound field control device 100 with various kinds of music, such as music recorded on a CD or HDD, car navigation voice guidance, telephone voice, radio broadcast, and sound information distributed from a server on the Internet. Output in format. In FIG. 1, the configuration of one signal reproduction device 200 is shown, but the signal reproduction device 200 may be a plurality of devices.

  A plurality of speakers 300 are installed in the closed space. For example, in the example shown in FIG. 2, it is installed in 24 places in the passenger compartment of an automobile. In FIG. 2, the position of the speaker 300 is indicated by a white circle as “sound source position”.

  The sound field control device 100 includes a signal separation unit 101, an environmental sound signal adjustment unit 102, an acoustic signal generation unit 103, a signal addition unit 104, a plurality of acoustic output units 105, a storage unit 106, and a setting unit 107. With.

  The signal separation unit 101 separates the sound information input from the signal reproduction device 200 and outputs the sound information to the environmental sound signal adjustment unit 102 or the acoustic signal generation unit 103 according to the sound information.

  The signal separation unit 101 does not need to control the sound field independently, and outputs sound information to be heard in common in each region to the environmental sound signal adjustment unit 102. The signal separation unit 101 outputs sound information that needs to control the sound field independently to the acoustic signal generation unit 103.

  For example, when the sound information is in the 5.1ch format, the signal separation unit 101 can also separate the sound information distributed to the center speaker.

  The environmental sound signal adjustment unit 102 outputs the sound information input from the signal separation unit 101 to the signal addition unit 104.

  The acoustic signal generation unit 103 generates a plurality of acoustic signals for each of a plurality of input sound information through a filter having a filter coefficient corresponding to a transmission target area of each sound information. The acoustic signal generation unit 103, for example, has a driver's seat (region A) as a target area for transmitting voice guidance by car navigation, the voice guidance is easy to hear in the region A, and is hardly audible on the left side of the rear seat (region B). When doing so, the sound information of the voice guidance is passed through a filter having a filter coefficient for region A (filter for region A), and an acoustic signal is generated and output to the signal adding unit 104. Here, the filter for the region A is a filter that controls the sound field of the region A as a center. For example, the filter for controlling the sound field is easy to hear in the region A and hardly hear in the region B.

  The acoustic signal generation unit 103 can change the filter characteristics according to the setting by the setting unit 107. The acoustic signal generation unit 103 reads out filter coefficients necessary for changing the filter characteristics from the storage unit 106 in accordance with the setting by the setting unit 107.

  The signal addition unit 104 adds the plurality of acoustic signals input from the environmental sound signal adjustment unit 102 and the acoustic signal generation unit 103 and outputs the result to the plurality of acoustic output units 105.

  The sound output unit 105 supplies the sound signal added by the signal adding unit 104 to the speaker 300. The number of sound output units 105 corresponds to the number of speakers 300.

  The storage unit 106 stores filter coefficients of filters used by the acoustic signal generation unit 103. The storage unit 106 stores filter coefficients for each region. The storage unit 106 stores a plurality of filter coefficients having different settings for each region.

  The setting unit 107 receives various settings from the user and outputs the received settings to the acoustic signal generation unit 103. Details of the contents set by the setting unit 107 will be described later.

  Here, the filter coefficients stored in the storage unit 106 will be described with reference to FIGS. 2 and 3. The filter coefficient is stored in the storage unit 106 in advance, but is calculated by the following method.

  FIG. 2 is a diagram showing the position of the speaker 300 (sound source position) and the position of the microphone (measurement position) installed in the passenger compartment of the automobile. In the example shown in FIG. 2, the speakers are installed at 24 locations. In the example shown in FIG. 2, microphones are installed in the area A (driver's seat) and the area B (rear seat left side). The position of the microphone is indicated by a black circle.

  By actually outputting sound from each speaker 300 and measuring the sound with each microphone, the transfer function can be measured for the combination of each speaker 300 and each microphone. In the example shown in FIG. 2, there are a plurality of speakers and microphones, and the relationship between the sound source and the sound field can be defined as a transfer matrix G.

The sound pressure response H by the sound source array composed of a plurality of sound sources (speakers) is obtained by the following equation (3).

Here, A _F is a vector expressing the relative sound source intensity or phase difference between the sound sources. If the target sound field is given by H _target , the necessary sound source condition can be obtained by the following equation (4).

Here, (G) ⁺ is a pseudo inverse matrix of G.

In order to optimize the input power input to the sound source, an error J between the target sound field H _target and the actual sound field (sound pressure response) H (= GA _F ) in an optimization problem such as the following equation (5) Find the solution A _F that minimizes.

Here, H in the upper right means a transposed matrix. When Formula (5) is solved for A _{F with} J = 0, the following Formula (6) can be transformed.

Here, the regularization coefficient β is a weight value of the diagonal component, and I is a unit matrix. The storage unit 106 stores a filter coefficient corresponding to A _F thus obtained.

  Equation (5) has the same form as Tikhonov regularization, which reduces the effect of noise by reducing the number of conditions in simultaneous equations. By applying a weight to the diagonal components of the matrix, It is a method of lowering.

  Here, the “condition number” is an index for evaluating the sensitivity of the system to an error. By configuring the system so that the condition number is small, the robustness of the system can be improved. In a closed space with a small volume, such as the interior of an automobile, an error is likely to occur in the transfer function. Therefore, it is effective to increase the robustness by reducing the condition number.

FIG. 3 is a conceptual diagram showing how sound pressure concentration solutions obtained for each control region by multi-region sound field control are combined based on the principle of superposition. Various methods other than the inverse problem method have been proposed for the sound pressure concentration problem, but the inverse problem method is applied to reflect the characteristics of a narrow internal space. First, a filter that does not transmit sound to one region A and transmits sound to another region B is introduced. Next, the region A and the region B are exchanged to transmit the sound to the region B, and a filter that does not transmit the sound to the other region A is introduced. By using these two filters in an overlapping manner, the sound field of each region can be controlled independently. _Assuming that the target sound fields in the region A and the region B are H _{target, A} and H _{target, B} , respectively, the target sound field can be expressed by the following equations (7) and (8), respectively.

Here, _AT is the sound source intensity of the sound source constituting the virtual sound field to be created, and W is the transfer matrix of the free sound field.

  In the following, we show how the sound field is actually separated.

The regularization coefficient β in the equations (5) and (6) is not uniquely determined and can take various forms. For example, the regularization coefficient β can be in the form shown in the following equation (9).

  Here, f is a frequency. Α and b are numbers that satisfy α> 0 and b> 0.

As an example, FIG. 4 shows a result of comparing the average sound pressure levels in the region A and the region B when the filter coefficient is calculated using the regularization coefficient β as the following formula (10). Here, the average sound pressure level is an average value of sound pressure levels measured by a plurality of microphones installed in the region.

  The horizontal axis in FIG. 4 is the frequency, and the vertical axis is the averaged sound pressure level. 4A shows the sound pressure level of the signal that has passed through the filter for region A, and FIG. 4B shows the sound pressure level of the signal that has passed through the filter for region B. In FIG. 4A, the sound pressure level measured in the region A over the entire frequency band of 200 Hz to 2 kHz is larger than the sound pressure level measured in the region B, and the sound field can be effectively separated. However, in FIG. 4B, the sound field cannot be effectively separated, for example, there is a frequency where the sound pressure level measured in the region A is higher than the sound pressure level measured in the region B.

Next, FIG. 5 shows a result when the regularization coefficient β is set to the following expression (11).

  FIG. 5 is a diagram showing a result of comparing the average sound pressure levels in the region A and the region B when the regularization coefficient β is β = 40 / √f. 5A shows the sound pressure level of the signal that has passed through the filter for region A, and FIG. 5B shows the sound pressure level of the signal that has passed through the filter for region B. In FIG. 5A, the sound pressure level measured in the region A over the entire frequency band of 200 Hz to 2 kHz is 10 dB or more larger than the sound pressure level measured in the region B, and the sound field can be effectively separated. Also in FIG. 5B, the sound pressure level measured in the region B over the entire frequency band of 200 Hz to 2 kHz is 10 dB or more higher than the sound pressure level measured in the region A, and the sound field can be effectively separated. Yes.

  FIG. 6 is a diagram showing the difference in sound pressure level in each region when the regularization coefficient β is in the form β = α / √f and the value α is used. In region A, the difference in sound pressure level increases as α decreases, and in region B, the difference in sound pressure level increases as α increases.

  Thus, since the difference in the sound pressure level varies depending on the value of α, the sound pressure level is set by setting the setting unit 107 and changing the value of the regularization coefficient β by making the value of α variable, for example. Can be controlled. In the present embodiment, the user sets α with the setting unit 107, and the acoustic signal generation unit 103 controls the difference in sound pressure level by processing the signal with a filter corresponding to the set α. it can. Thereby, for example, in the area A, it is possible to control so that only one of the two pieces of sound information can be heard easily, or the two pieces of sound information can be heard to the same extent.

  FIG. 7 compares the number of conditions when the regularization coefficient β is β = 1 / f and β = 40 / √f. It is assumed that when β = 40 / √f, the condition number is smaller than when β = 1 / f, and the smaller the condition number, the greater the sound field separation effect.

[Volume control]
The setting unit 107 can accept a volume setting for each piece of sound information from the user. The setting unit 107 outputs the received volume setting to the acoustic signal generation unit 103, and the acoustic signal generation unit 103 adjusts the volume according to the volume setting. Thereby, the mixing ratio of two sound information can be changed in each area | region. Further, when it is desired to adjust the mixing ratio of sound information for each frequency, the mixing ratio can be adjusted for each frequency by using an equalizer for input information.

  FIG. 8 shows an example of an operation interface for operating volume in multiple areas. For example, when the operation interface is a touch screen, an independent volume can be operated for each piece of sound information by performing operations such as pinch-in and pinch-out. Note that the example illustrated in FIG. 8 is merely an example, and the operation interface may be based on a different method.

[Sound image operation]
In the expressions (7) and (8), the target sound fields H _{taget, A} and H _{target, B} can be freely expressed in the two areas A and B. For example, when there is no sound image in the area A, the target sound field is set to 1 in all the microphones in the area A. Further, when a sound image is added in the region A, for example, when a sound image is desired from the horizontal wall surface, the microphone on the opposite side of the horizontal wall surface is set to less than 1. Thus, the position of the sound image can be controlled by considering the input balance to the microphone for each target sound field.

  The setting unit 107 can accept sound image settings from the user. The setting unit 107 outputs the received sound image setting to the acoustic signal generation unit 103, and the acoustic signal generation unit 103 reads the filter coefficient corresponding to the sound image setting from the storage unit 106 and adjusts the sound image. FIG. 9 shows an example of an operation interface for operating a sound image. FIG. 9A is an example of an operation interface for designating a sound image position for each region. In the example shown in FIG. 9A, for example, in the area A, the sound image position is set to the front right, and in the area B, the sound image position is set to the front left. FIG. 9B is an example of an operation interface for designating a sound image position for each signal. In the example shown in FIG. 9B, for example, the sound image position of the signal A is set to the front right, and the sound image position of the signal B is set to the front left.

[Select sound source (speaker)]
Up to now, the installation position of the sound source (speaker) has been described as being given in advance. However, by appropriately selecting the position of the sound source that easily affects the control area, it is possible to eliminate the surplus and efficiently arrange the sound source. Can be Hereinafter, a method for appropriately selecting a sound source position will be described.

  FIG. 10 is a diagram showing a schematic configuration of a speaker arrangement selection device 400 according to an embodiment of the present invention. The speaker arrangement selection device 400 includes an acoustic signal transmission unit 401, an acoustic signal reception unit 402, an acoustic transfer function calculation unit 403, an EfI value calculation unit 404, a speaker number setting unit 405, and a speaker arrangement selection unit 406. .

  The acoustic signal transmission unit 401 outputs sound from the speaker according to a predetermined initial signal. FIG. 11 shows an example in which 64 speakers are installed as the initial arrangement number in the interior of a car.

  The acoustic signal receiving unit 402 receives, for example, an acoustic signal received by a microphone installed around the area A and the area B from the microphone.

  The acoustic transfer function calculation unit 403 calculates the transfer matrix G based on the signal input from the acoustic signal transmission unit 401 and the signal input from the acoustic signal reception unit 402, and outputs the transfer matrix G to the EfI value calculation unit 404.

  The EfI value calculation unit 404 calculates an EfI (Effective Independence) value based on the transfer matrix G input from the acoustic transfer function calculation unit 403 and the number of speakers acquired from the speaker number setting unit 405. Details of the method of calculating the EfI value will be described later.

  The number-of-speakers setting unit 405 receives an input of the number of speakers desired to be installed from the user, and outputs it to the EfI value calculation unit 404 and the speaker arrangement selection unit 406.

  The speaker arrangement selection unit 406 selects a speaker based on the EfI value of each speaker acquired from the EfI value calculation unit 404. The number of speakers selected by the speaker arrangement selection unit 406 is the number acquired from the number-of-speakers setting unit 405. The speaker arrangement selection unit 406 sets the number of speakers having higher EfI values set in the number-of-speakers setting unit 405. Select only for.

  Hereinafter, processing in the EfI value calculation unit 404 will be described.

  The EfI value calculation unit 404 calculates an EfI value by an EfI method (Effective Independence Method). The EfI method is a method of evaluating the linear independence of rows and columns constituting a matrix and evaluating the overlapping degree of the components. An element with high linear independence means a highly necessary component, and an element with low linear independence means an extra component with low necessity. The number of conditions can be reduced by selecting components with high linear independence and eliminating excess components.

The EfI value calculation unit 404 acquires the transfer matrix G from the acoustic transfer function calculation unit 403, and performs singular value decomposition as shown in the following equation (12).

  Here, if the number of microphones is m and the number of speakers is n, the transfer matrix G is an m × n matrix. U is an m × m orthogonal matrix, Λ is an m × n diagonal matrix, and W is an n × n orthogonal matrix. H in the upper right of W means a transposed matrix.

  Subsequently, the EfI value calculation unit 404 generates a matrix Wa using the number of speakers acquired from the speaker number setting unit 405. Wa is an n × a matrix, where “a” is the number of speakers acquired from the speaker number setting unit 405. The EfI value calculation unit 404 generates the matrix Wa by selecting the first to a-th column vectors of the matrix W. For example, when 24 speakers are selected from 64 speakers, n = 64 and a = 24.

Subsequently, the EfI value calculation unit 404 calculates a vector E _{W of} EfI values as shown in the following equation (13).

  Here, the function diag is a function for performing an operation of extracting a diagonal component and generating a column vector.

Component of vector E _W corresponds to EfI value of the speakers, has a value between 0 and 1. The EfI value means that the higher the numerical value, the higher the linear independence. The number of conditions can be reduced by selecting a speaker having a high EfI value, and the sound field can be controlled efficiently.

  FIG. 12 shows an example of selecting 24 speakers having a high EfI value (that is, 24 speakers having high linear independence) from 64 speakers.

  FIG. 13 is a diagram illustrating a state in which the number of conditions is compared between 64 speakers and 24 selected speakers. As shown in FIG. 13, the condition number is lowered by selecting 24 speakers having high linear independence from 64 speakers. Therefore, it can be seen that the speakers are appropriately arranged with respect to the sound field.

  According to this method, an appropriate sound source arrangement can be selected even in a space with a lot of reflection such as a glass surface, and this method can be applied in various spaces without any particular limitation.

  As described above, according to the present embodiment, for each of a plurality of sound information, a plurality of acoustic signals are generated through a filter having a filter coefficient corresponding to a region to which each sound information is to be transmitted. The sound field can be controlled so that important sound information can be heard independently for each region.

  Further, the filter coefficient is calculated as a solution of the optimization problem related to the transfer matrix and the target sound field, and the regularization coefficient β included in the solution of the optimization problem is set by the setting unit 107, so that the multi-field sound field is separated. It is possible to control the degree to be made.

  In addition, the setting unit 107 can control the volume ratio of multiple areas by setting the volume of multiple pieces of sound information in each of multiple areas.

  In addition, by setting the sound image positions in the plurality of areas by the setting unit 107, the sound image positions in multiple areas can be controlled.

  Further, by selecting and arranging the speaker 300 having a high EfI value by the speaker arrangement selection device 400, the linear independence of the selected speaker 300 can be enhanced, and the speaker 300 can be arranged efficiently. .

  Although the present invention has been described based on the drawings and examples, it should be noted that those skilled in the art can easily make various modifications and corrections based on the present disclosure. Therefore, it should be noted that these variations and modifications are included in the scope of the present invention. For example, the functions included in each component, each step, etc. can be rearranged so that there is no logical contradiction, and multiple components, steps, etc. can be combined or divided into one It is. Further, although the present invention has been described mainly with respect to the apparatus, the present invention can also be realized as a method, a program executed by a processor included in the apparatus, or a storage medium storing the program, and is within the scope of the present invention. It should be understood that these are also included.

DESCRIPTION OF SYMBOLS 10 Sound field control system 100 Sound field control apparatus 101 Signal separation part 102 Environmental sound signal adjustment part 103 Acoustic signal generation part 104 Signal addition part 105 Sound output part 106 Storage part 107 Setting part 200 Signal reproduction apparatus 300 Speaker 400 Speaker arrangement | positioning selection apparatus 401 Acoustic signal transmission unit 402 Acoustic signal reception unit 403 Acoustic transfer function calculation unit 404 EfI value calculation unit 405 Speaker number setting unit 406 Speaker arrangement selection unit

Claims (12)

In a closed space having a plurality of speakers, a sound field control device for controlling a sound field in the closed space by a plurality of input sound information,
For each of the plurality of sound information, an acoustic signal generation unit that generates a plurality of acoustic signals through a filter having a filter coefficient corresponding to a transmission target area of each sound information;
A signal adder for adding the plurality of acoustic signals;
An acoustic output unit that supplies the added acoustic signals to the plurality of speakers;
The sound field control device, wherein the filter coefficient is calculated based on a transfer matrix from the plurality of speakers to a plurality of regions in the closed space and a target sound field in the plurality of regions.   The sound field control device according to claim 1, wherein the filter coefficient is calculated as a solution to an optimization problem related to the transfer matrix and the target sound field.   3. The sound field control apparatus according to claim 2, wherein the solution of the optimization problem includes a regularization coefficient β, and the filter coefficient has a different value according to the regularization coefficient β. Control device. 4. The sound field control device according to claim 3, wherein the solution of the optimization problem is given by the following equation (1).

In Equation (1), A _F represents the solution of the optimization problem, G represents the transfer matrix, β represents the regularization coefficient, I represents the unit matrix, and H _target represents the target sound field. 5. The sound field control device according to claim 4, wherein the regularization coefficient β is given by the following equation (2).

However, in Formula (2), f shows a frequency and (alpha) and b show the number used as (alpha)> 0 and b> 0.   6. The sound field control device according to claim 5, wherein b = 1/2.   The sound field control device according to any one of claims 3 to 6, further comprising a setting unit that sets the regularization coefficient β.   The sound field control device according to claim 7, wherein the setting unit sets sound volumes of the plurality of sound information in the plurality of regions, respectively.   The sound field control device according to claim 7, wherein the setting unit sets a sound image position in each of the plurality of regions. A sound field control system comprising a sound field control device for controlling a sound field in the closed space by a plurality of sound information inputted in a closed space, and a plurality of speakers,
The sound field control device includes:
For each of the plurality of sound information, an acoustic signal generation unit that generates a plurality of acoustic signals through a filter having a filter coefficient corresponding to a transmission target area of each sound information;
A signal adder for adding the plurality of acoustic signals;
An acoustic output unit that supplies the added acoustic signals to the plurality of speakers;
The sound field control system, wherein the filter coefficient is calculated based on a transfer matrix from the plurality of speakers to a plurality of regions in the closed space and a target sound field in the plurality of regions. The sound field control system according to claim 10,
The plurality of speakers are speakers selected by a speaker arrangement selection device,
The speaker arrangement selection device includes:
In a state in which a speaker having an initial arrangement number greater than the number of the plurality of speakers is installed, singular value decomposition is performed on a transfer matrix from the initial arrangement number of speakers to a plurality of regions in the closed space,
EffI (Effective Independence) value of the initial arrangement number is calculated from the orthogonal matrix obtained by the singular value decomposition,
The sound field control system, wherein the plurality of speakers are selected by selecting a desired number of speakers having higher EfI values from the initial number of EfI values. A sound field control method for controlling a sound field in a closed space by a plurality of sound information inputted in a closed space having a plurality of speakers,
For each of the plurality of sound information, generating a plurality of acoustic signals through a filter having a filter coefficient corresponding to a transmission target area of each sound information;
Adding the plurality of acoustic signals;
Supplying the added acoustic signals to the plurality of speakers,
The sound field control method, wherein the filter coefficient is calculated based on a transfer matrix from the plurality of speakers to a plurality of regions in the closed space and a target sound field in the plurality of regions.

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