JP2009027331A - Sound field reproduction system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reproduce the acoustic characteristics of an original sound field in multichannel sound output of a reproduced sound field by using acoustic characteristics of the original sound field having a multichannel sound output capability. <P>SOLUTION: An acoustic processing means 40 of a sound field reproduction system 1 performs acoustic processing using a sound field reproduction filter capable of reproducing acoustic characteristics of each speaker in the original sound field in the reproduced sound field 21 based on the acoustic characteristics of each speaker 23 in the reproduced sound field 21. Thereby, sound signals which have been subjected to acoustic processing can be output in the reproduced sound field 21 in correspondence with a multichannel sound signal. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sound field reproduction system, and more particularly to a sound field reproduction system capable of performing an acoustic process on an acoustic signal reproduced by an acoustic reproduction unit and outputting the acoustic signal from an output unit.

  Conventionally, after recording (measuring) the sound field characteristics of a certain space (original sound field), sound field reproduction that virtually reproduces the sound field characteristics of the original sound field measured in a different space (reproduced sound field) from that space A method has been proposed. As a method for spatially reproducing a sound field, for example, there are methods such as a wavefront synthesis method (for example, see Patent Document 1) and a boundary sound field control method by multi-channel-multipoint control (for example, see Patent Document 2). Are known.

  Both methods calculate a sound field reproduction filter for reproducing the sound field based on the acoustic characteristics recorded in the original sound field, and use the calculated sound field reproduction filter to perform convolution calculation processing of the sound source (for example, an FIR filter). By performing the convolution calculation process used, the original sound field is virtually reproduced in a different space (reproduced sound field). By using such a sound field reproduction method, the listener can obtain a feeling as if he / she is listening in the original sound field in the reproduced sound field.

On the other hand, in recent home audio systems and in-vehicle audio systems, not only the conventional monaural output and stereo output (2-channel output) but also an acoustic system having a multi-channel output (for example, 5.1 channel output). Is used. In such a multi-channel sound system, an optimal sound field corresponding to the space in which the sound system is installed, the sound characteristics of the speaker, and the installation position is achieved by applying sound effects and gain / delay processing to each channel. It is possible to do.
JP 2003-323179 A Japanese Patent Laid-Open No. 2005-249989

  By the way, when reproducing the sound field in an acoustic system having such a multi-channel output by another acoustic system having a multi-channel output, the number of channels of the input sound source, the number of speakers used in the original sound field, etc. It is necessary to build a reproduction environment that takes into account.

  Specifically, when reproducing the sound field in an acoustic system with a multi-channel output on another acoustic system with a multi-channel output, the impulse response evaluation sound is simultaneously output from the speakers of all channels in the original sound field. A method of recording output sound from a speaker with a plurality of microphones is conceivable.

  However, when reproducing the sound field characteristics in the reproduced sound field using the acoustic characteristics of the original sound field measured in this way, the sound signals output from a plurality of channels are simultaneously measured with microphones in the original sound field. Since the acoustic characteristics are measured, the multi-channel acoustic characteristics in the original sound field are reproduced as single-channel acoustic characteristics in the reproduced sound field. For this reason, the acoustic characteristics of the original sound field cannot be reproduced using a sound system with multi-channel output in the reproduced sound field, and the parameters of the acoustic effect and gain / delay processing are set for each channel in the reproduced sound field. There was a problem that it could not be changed.

  The present invention has been made in view of the above problems, and reproduces the acoustic characteristics of the original sound field in the multi-channel sound output of the reproduced sound field by using the acoustic characteristics of the original sound field corresponding to the multi-channel sound output. It is an object of the present invention to provide a sound field reproduction system that can be used.

  In order to solve the above problems, a sound field reproduction system according to the present invention includes an acoustic reproduction unit capable of reproducing an acoustic signal having multi-channel acoustic information, and an acoustic signal reproduced by the acoustic reproduction unit. Is output from a plurality of speakers according to the multi-channel sound information, and the sound signal reproduced by the sound reproducing means is subjected to sound processing and output from the first output means. Acoustic processing means, and the acoustic processing means is provided with acoustic characteristics for each speaker of the first output means and a second output means having a plurality of speakers in a reproduction sound field where the first output means is installed. Based on the acoustic characteristics of each speaker in the generated original sound field, the sound field reproduction field capable of reproducing the acoustic characteristics of the original sound field in the reproduced sound field. For each speaker of the second output means, and for a multi-channel sound signal reproduced by the sound reproduction means, the sound field of the speaker corresponding to the channel of the sound signal And a sound control means for performing a convolution operation on the reproduction filter, adding the sound signal obtained by the convolution operation for each speaker component, and outputting the result to each speaker of the first output means according to the channel of the sound signal. Features.

  According to the sound field reproduction system according to the present invention, the multi-channel sound reproduced by the sound reproducing means using the sound field reproduction filter capable of reproducing the acoustic characteristics of each speaker in the original sound field in the reproduced sound field. Since the sound processing is performed on the signal, it is possible to reproduce the acoustic characteristics of the original sound field corresponding to the output of the multi-channel sound signal in the multi-channel sound signal in the reproduced sound field.

  For this reason, acoustic processing corresponding to the multi-channel acoustic signal can be performed for each channel in the reproduced sound field, and independent sound source adjustment processing can be performed for each multi-channel. Therefore, when an audio effect or gain / delay processing is performed for each channel in an audio device, the sound effect or the like can be effectively and faithfully reflected in the reproduced sound field.

  Further, in the sound field reproduction system according to the present invention, the sound control means performs a convolution operation on the sound field reproduction filter of the speaker corresponding to the channel of the sound signal with respect to the multi-channel sound signal reproduced by the sound reproduction means, The acoustic processing is performed by adding and calculating the convolutional acoustic signal for each speaker component. For this reason, by selecting / controlling the channels to be added and calculated, it becomes possible to emphasize / weakly adjust the sound signal of a specific channel, and arbitrarily select the combination of channels to be added / calculated. It is possible to reproduce various sound fields.

  In the sound field reproduction system described above, the acoustic characteristics of each speaker of the first output means in the reproduced sound field are set in the reproduction sound field by the evaluation sound output for each speaker by the first output means. It may be calculated based on the recorded sound collected for each speaker by the sound collecting means.

  Thus, when the acoustic characteristics for each speaker in the reproduced sound field are calculated based on the recorded sound for each speaker collected by the sound collecting means, the acoustic characteristics in the reproduced sound field are It is possible to calculate corresponding to the output sound of the multi-channel corresponding to the number.

  In addition, the acoustic characteristics of each speaker of the second output means in the original sound field is obtained by collecting the evaluation sound output for each speaker by the second output means for each speaker by the sound collecting means installed in the original sound field. It may be calculated based on the recorded sound.

  Thus, even when the acoustic characteristics for each speaker in the original sound field are calculated based on the recorded sound for each speaker picked up by the sound collecting means, the acoustic characteristics in the original sound field are set as the number of speakers. It is possible to calculate corresponding to the corresponding multi-channel output sound.

  Further, in the sound field reproduction system described above, the sound processing means records original sound field characteristic recording means for recording the sound characteristic of each speaker of the second output means in the original sound field, and the first sound field in the reproduction sound field. Reproduced sound field characteristic recording means for recording acoustic characteristics for each speaker of the output means, acoustic characteristics of the reproduced sound field recorded in the original sound field characteristic recording means, and recorded in the reproduced sound field characteristic recording means An acoustic reproduction information calculating unit that calculates the sound field reproduction filter based on the acoustic characteristics of the original sound field may be included.

  As described above, since the sound processing means has the sound reproduction information calculation means for calculating the sound field reproduction filter, the sound field reproduction filter can be calculated in the reproduction sound field, and the system configuration can be simplified. Can be planned. Further, by performing the calculation process of the sound field reproduction filter in the sound field reproduction system, it is possible to facilitate and speed up the process.

  According to the sound field reproduction system according to the present invention, when the original sound field is a sound field environment capable of outputting a multi-channel sound signal, the sound characteristics of the original sound field corresponding to the output of the multi-channel sound signal. Can be reproduced in a multi-channel acoustic signal in a reproduced sound field.

  Hereinafter, the sound field reproduction system according to the present invention will be described in detail with reference to the drawings. In the sound field reproduction system according to the present embodiment, the boundary sound field control method is used as the sound field reproduction method. The boundary sound field control method is that when listening to the output sound in the reproduced sound field, a plurality of control points are installed around the listener's head or in the vicinity of the auricle (earlobe). This is a method of perceiving the original sound field audibly by controlling the reproduced sound field so that the field characteristics are reproduced.

  First, a method for measuring the acoustic characteristics of the original sound field reproduced by the sound field reproduction system using the original sound field sound system will be described.

[Measurement of acoustic characteristics in the original sound field]
As shown in FIG. 1, the original sound field sound system 2 includes a speaker unit (second output means) 3 installed in an acoustic space (original sound field) 6 that is desired to be reproduced, and sound that outputs sound to the speaker unit 3. The output device 4, the computer 5 that outputs the evaluation sound to the audio output device 4, the microphone array (sound collecting means) 7 installed in the original sound field 6, and the input of the recorded sound collected by the microphone array 7 And a voice input device 8 that performs the above.

  In the present embodiment, the acoustic environment in the passenger compartment is used as an example of the original sound field 6. By using the vehicle interior space as the original sound field 6 in this way, the acoustic environment in the vehicle interior can be faithfully reproduced in a reproduced sound field described later. For this reason, when the reproduced sound field is, for example, a laboratory, it is possible to reproduce the vehicle interior characteristics of any vehicle in the laboratory by using the acoustic characteristics measured in the original sound field 6.

  As shown in FIG. 1, the speaker unit 3 includes a front right speaker FR installed at a right door position on the front seat side of the vehicle 10, a front left speaker FL installed at a left door position on the front seat side, and a rear A rear right speaker RR installed at the right door position on the seat side and a rear left speaker RL installed at the left door position on the rear seat side are provided. Each speaker FR, FL, RR, RL is a general speaker used in a general vehicle 10.

  The audio output device 4 has a role of outputting the evaluation sound output from the computer 5 to each speaker FR, FL, RR, RL of the speaker unit 3. Note that the audio output device 4 can individually output the output destination of the evaluation sound to the speakers FR, FL, RR, RL according to the control command of the computer 5. Note that the evaluation sound is an output sound used to calculate the acoustic characteristics of the original sound field 6 based on the recorded sound collected via the microphone array 7 and the sound input device 8, and specifically, A sound suitable for measuring the collected recorded sound as an impulse response (impulse input sound) is applicable.

  The microphone array 7 is composed of a group of microphones in which a plurality of (for example, M) microphones 12 are arranged in a circle. The microphone array 7 is a driver's seat 13 in the passenger compartment, and is installed at a height that assumes the head position of the driver. In the present embodiment, by collecting the evaluation sound at the driver's head position with the microphone array 7, it is possible to measure the acoustic characteristics of the vehicle interior mainly composed of the driver.

  The voice input device 8 has a role of outputting the output sound of the speaker unit 3 measured by the microphone array 7 to the computer 5. Here, although a plurality of microphones 12 are installed in the microphone array 7, the acoustic signal of the microphone array 7 input in the voice input device 8 becomes an input signal input simultaneously by the plurality of microphones 12. Input is performed as an acoustic signal of the channel.

  The computer 5 has a function of generating the above-described evaluation sound and measuring the acoustic characteristic of the original sound field 6 based on the recorded sound collected by the microphone array 7 in order to measure the acoustic characteristic in the passenger compartment. ing.

  The computer 5 is roughly configured by an evaluation sound generation unit 15, an impulse response calculation unit 16, an impulse response recording unit 17, and a control unit 18. The evaluation sound generator 15 has a function of generating an evaluation sound for collecting the impulse response described above. The evaluation sound generation unit 15 generates an evaluation sound in accordance with a control command from the control unit 18, and outputs the evaluation sound to the audio output device 4 via the control unit 18.

  The impulse response calculation unit 16 calculates an impulse response to the evaluation sound based on the recorded sound collected via the microphone array 7 and the voice input device 8. The impulse response calculated here is calculated for each speaker according to the speakers FR, FL, RR, and RL to which the evaluation sound selected by the audio output device 4 is output.

  The impulse response recording unit 17 records the impulse response calculated for each of the speakers FR, FL, RR, and RL as acoustic characteristics. The impulse response recording unit 17 may be a general hard disk or the like, or may be composed of a RAM (Random Access Memory), a flash memory, or the like.

  The control unit 18 has a role of performing processing necessary for obtaining acoustic characteristics for each of the speakers FR, FL, RR, and RL in the original sound field 6, and includes a CPU (Central Processing Unit) that mainly performs arithmetic control processing, A general arithmetic processor such as a ROM (Read Only Memory) in which a program for measuring acoustic characteristics in the original sound field is recorded and a RAM (Random Access Memory) used in a work area or the like is used.

  As described above, the control unit 18 causes the evaluation sound generation unit 15 to generate an evaluation sound and has a role of outputting the generated evaluation sound to the sound output device 4. Further, the control unit 18 has a role of switching and controlling the speakers FR, FL, RR, and RL of the evaluation sound output from the sound output device 4 by outputting a control command to the sound output device 4. ing. Furthermore, the control unit 18 causes the impulse response calculation unit 16 to calculate the impulse response for each speaker based on the recorded sound input from the voice input device 8, and the calculated impulse response for each speaker is used as the sound in the original sound field 6. As a characteristic, the impulse response recording unit 17 has a role of recording.

  FIG. 2 is a flowchart showing an acoustic characteristic measurement process of the original sound field 6 in the control unit 18.

  In the original sound field acoustic system 2 configured as described above, the control unit 18 outputs a control command for generating the evaluation sound to the evaluation sound generation unit 15 (step S.1). The evaluation sound generation unit 15 generates an evaluation sound in accordance with a control command from the control unit 18 and outputs the evaluation sound to the control unit 18.

  Next, the control unit 18 determines an output destination speaker (output channel) of the evaluation sound to be selected by the audio output device 4 (step S.2). Specifically, the control unit 18 determines whether to output the evaluation sound to the front right speaker FR, the front left speaker FL, the rear right speaker RR, or the rear left speaker RL. And the control part 18 outputs the output destination speaker information determined with respect to the audio | voice output apparatus 4 (step S.3), and outputs an evaluation sound with respect to the audio | voice output apparatus 4 (step S.4).

  In the audio output device 4, the output destination of the evaluation sound is set to the designated speaker according to the output destination speaker information received from the control unit 18, and the evaluation sound is output. In the microphone array 7, output sounds output from designated speakers are collected by a plurality (M) of microphones 12, and the collected recording sounds are output to the voice input device 8. The voice input device 8 outputs the recorded sound acquired from the microphone array 7 to the control unit 18.

  The control unit 18 acquires a recorded sound from the voice input device 8 (step S.5), and outputs an impulse response calculation processing instruction to the impulse response calculation unit 16 based on the acquired recorded sound to calculate the impulse response. Processing is performed (step S.6). Then, the impulse response calculated by the impulse response calculation unit 16 is recorded in the impulse response recording unit 17 in association with the speaker from which the evaluation sound is output (step S.7).

  Thereafter, the control unit 18 determines whether or not the evaluation sound output processing has been performed for all the speakers (step S.8), and there is a speaker that has not yet performed the evaluation sound output processing (step S.8). In the case of No in step 8), the process proceeds to step S. The process proceeds to 2 to determine an output destination speaker that has not yet undergone evaluation sound output processing (step S.2), and the above-described processing is repeatedly executed.

  When evaluation sound output processing is performed for all speakers (Yes in step S.8), in the present embodiment, front right speaker FR, front left speaker FL, rear right speaker RR, rear left speaker RL. When the evaluation sound is output for each of the above, the control unit 18 ends the acoustic characteristic measurement process of the original sound field 6 in the original sound field acoustic system 2.

  In this way, the control unit 18 measures the acoustic characteristics in the original sound field 6, whereby the acoustic characteristics between the speakers FR, FL, RR, RL and the microphones 12 can be obtained for each speaker. The acoustic characteristics obtained in this manner are the acoustic characteristics of the front right speaker FR, the acoustic characteristics of the front left speaker FL, the acoustic characteristics of the rear right speaker RR, and the acoustic characteristics of the rear right speaker RL in the impulse response recording unit 17. It is recorded as four types of acoustic characteristics.

[Measurement of acoustic characteristics in reproduced sound field]
Next, a reproduced sound field acoustic system for measuring acoustic characteristics in a reproduced sound field will be described. In this embodiment, a laboratory is used as an example of a reproduced sound field. As described above, by using the laboratory as a reproduction sound field, the acoustic environment of the vehicle interior (original sound field 6) described above can be faithfully reproduced in the experiment room. For this reason, by measuring the acoustic characteristics of different vehicles in the above-described original sound field acoustic system 2, it becomes possible to reproduce the acoustic environment of any vehicle in one laboratory (reproduced sound field).

  As shown in FIG. 3, the reproduced sound field acoustic system 20 includes a speaker unit 22 installed in a laboratory (reproduced sound field) 21, a sound output device 4 that outputs sound to the speaker unit 22, and a sound output. A computer 5 that outputs an evaluation sound to the device 4, a microphone array 7 installed in the original sound field 6, and a voice input device 8 that inputs the recorded sound collected by the microphone array 7. Yes.

  Here, the audio output device 4, the computer 5, the microphone array 7, and the audio input device 8 used in the reproduced sound field acoustic system 20 are the audio output device 4 used in the original sound field acoustic system 2 described above, Since the computer 5, the microphone array 7, and the voice input device 8 have the same configuration and the same functions, detailed descriptions thereof are omitted. In addition, the evaluation sound generator 15, the impulse response calculator 16, the impulse response recording unit 17, and the controller 18 that roughly configure the computer 5 also have the evaluation sound that roughly configures the computer 5 of the original sound field acoustic system 2 described above. Since the generator 15, the impulse response calculator 16, the impulse response recorder 17, and the controller 18 have the same configuration and the same functions, detailed descriptions thereof are omitted.

  As shown in FIG. 3, the speaker unit 22 includes a plurality of (N in this embodiment) speakers 23 arranged in a circle so as to maintain an equal distance from the microphone array 7. The speaker 23 can output the evaluation sound output from the audio output device 4.

  On the other hand, the audio output device 4 can individually output the output destination of the evaluation sound to each speaker 23 according to the control command of the computer 5, similarly to the audio output device 4 of the original sound field acoustic system 2 described above. It has become.

  FIG. 4 is a flowchart showing an acoustic characteristic measurement process of the reproduced sound field 21 in the control unit 18.

  In the reproduced sound field acoustic system 20 configured as described above, the control unit 18 outputs a control command for generating an evaluation sound to the evaluation sound generation unit 15 (step S.11). The evaluation sound generation unit 15 generates an evaluation sound in accordance with a control command from the control unit 18 and outputs the evaluation sound to the control unit 18.

  Next, the control part 18 determines the output destination speaker (output channel) of the evaluation sound selected in the audio | voice output apparatus 4 (step S.12). Specifically, the control unit 18 determines to which of the N speakers 23 the evaluation sound is to be output. And the control part 18 outputs the output destination speaker information determined with respect to the audio | voice output apparatus 4 (step S.13), and outputs an evaluation sound with respect to the audio | voice output apparatus 4 (step S.14).

  In the audio output device 4, the output destination of the evaluation sound is set to the designated speaker 23 according to the output destination speaker information received from the control unit 18, and the evaluation sound is output. In the microphone array 7, output sounds output from the designated speakers 23 are collected by a plurality (M) of microphones 12, and the collected recording sounds are output to the voice input device 8. The voice input device 8 outputs the recorded sound acquired from the microphone array 7 to the control unit 18.

  The control unit 18 acquires the recorded sound from the voice input device 8 (step S.15), and outputs an impulse response calculation processing command to the impulse response calculation unit 16 based on the acquired recorded sound, thereby calculating the impulse response. Processing is performed (step S.16). Then, the impulse response calculated by the impulse response calculation unit 16 is recorded in the impulse response recording unit 17 in association with the speaker 23 from which the evaluation sound is output (step S.17).

  Thereafter, the control unit 18 determines whether or not the evaluation sound output processing has been performed for all the speakers 23 (step S.18), and there is a speaker 23 that has not yet performed the evaluation sound output processing (step S.18). In the case of No in S.18), the process proceeds to step S.18. Then, the output destination speaker 23 for which the evaluation sound output processing has not yet been performed is determined (step S.12), and the above-described processing is repeatedly executed.

  When the evaluation sound output processing is performed for all the speakers 23 (Yes in step S.18), that is, by outputting the evaluation sound to each of the N speakers 23, each speaker 23 is output. When the impulse response calculation process is performed, the control unit 18 ends the acoustic characteristic measurement process of the reproduced sound field 21 in the reproduced sound field acoustic system 20.

The acoustic characteristics measured in the reproduced sound field acoustic system 20 are obtained based on a number of impulse responses between the N speakers 23 of the speaker unit 22 and the M microphones 12 of the microphone array 7. The acoustic characteristics A _ij obtained based on all the impulse responses are recorded in the impulse response recording unit 17.

[Calculation of sound field reproduction filter]
Next, a sound for realizing the acoustic environment of the original sound field 6 in the reproduced sound field 21 based on the acoustic characteristics calculated in the original sound field acoustic system 2 and the acoustic characteristics calculated in the reproduced sound field acoustic system 20. Processing for calculating the field reproduction filter will be described.

  FIG. 5 is a block diagram showing a filter calculation device 30 for calculating a sound field reproduction filter.

  The filter calculation device 30 includes a filter calculation processing unit (sound reproduction information calculation unit) 31, an original sound field characteristic recording unit (original sound field characteristic recording unit) 32, and a reproduced sound field characteristic recording unit (reproduced sound field characteristic recording unit) 33. And a filter information recording unit 34.

  The original sound field characteristic recording unit 32 records the acoustic characteristics measured in the original sound field 6, and, like the impulse response recording unit 17, a general hard disk, RAM (Random Access Memory), flash memory, or the like. It is constituted by a simple recording device. Similarly, the reproduced sound field characteristic recording unit 33 records acoustic characteristics measured in the reproduced sound field 21, and is configured by a general recording device such as a hard disk.

  The filter information recording unit 34 is a recording medium on which the sound field reproduction filter calculated by the filter calculation processing unit 31 is recorded. Similarly to the original sound field characteristic recording unit 32 and the reproduced sound field characteristic recording unit 33, the filter information recording unit 34 is also configured by a general recording device.

  The filter calculation processing unit 31 performs a process of calculating a sound field reproduction filter based on the acoustic characteristics recorded in the original sound field characteristic recording unit 32 and the acoustic characteristics recorded in the reproduction sound field characteristic recording unit 33. The filter calculation processing unit 31 includes a CPU (Central Processing Unit) that mainly performs arithmetic control processing, a ROM (Read Only Memory) in which a program for measuring acoustic characteristics in the original sound field 6 is recorded, a work area, and the like. It is constituted by a general arithmetic processor such as a RAM (Random Access Memory) used.

The filter calculation processing unit 31 calculates the sound field reproduction filter Q _j by solving the following determinant (Formula 1).

Here, the element A _ij of the matrix A indicates the acoustic characteristics between the speaker j and the microphone i in the reproduced sound field, the matrix Q _j indicates the desired sound field reproduction filter, and the matrix D _i is It shows the acoustic characteristics of the original sound field.

In addition, i indicates the number of microphones 12 installed in the microphone array 7, and M microphones 12 are installed in the microphone array 7 in the present embodiment.
i = 1, 2,..., M.

Furthermore, j indicates the number of speakers in the reproduced sound field, and N speakers 23 are installed in the speaker unit 22 of the reproduced sound field in the present embodiment.
j = 1, 2,..., N.

The filter calculation processing unit 31 performs sound field reproduction filters Q _j (Q _{1 to} Q _N ) corresponding to the speakers FR, FL, RR, and RL of the speaker unit 3 based on the above-described formula 1 according to the flowchart shown in FIG. Is obtained (step S.21).
At this time, the filter calculation processing unit 31 is based on the acoustic characteristic A _ij of the reproduced sound field 21.
(1) a sound field reproduction filter Q _j (FR) with respect to the acoustic characteristic D _i (FR) of the original sound field 6;
(2) a sound field reproduction filter Q _j (FL) for the acoustic characteristic D _i (FL) of the original sound field 6;
(3) a sound field reproduction filter Q _j (RR) with respect to the acoustic characteristic D _i (RR) of the original sound field 6;
(4) A sound field reproduction filter Q _j (RL) for the acoustic characteristic D _i (RL) of the original sound field 6 is calculated (step S.21).

The filter calculation processing unit 31 records the calculated sound field reproduction filters Q _j (FR), Q _j (FL), Q _j (RR), Q _j (RL) in the filter information recording unit 34 (step S.22), the calculation process of the sound field reproduction filter is terminated. In the flowchart shown in FIG. 6, only the calculation process of one sound field reproduction filter Q _j for one acoustic characteristic D _i is shown for convenience, but as described above, each acoustic characteristic of the original sound field 6 (described above) (1)-(4) acoustic characteristics D _i (FR), acoustic characteristics D _i (FL), acoustic characteristics D _i (RR), acoustic characteristics D _i (RL)) for each sound field reproduction filter (described above ( The sound field reproduction filter Q _j (FR), the sound field reproduction filter Q _j (FL), the sound field reproduction filter Q _j (RR), and the sound field reproduction filter Q _j (RL)) of 1) to (4) are calculated. Then, it is recorded in the filter information recording unit 34.

[Sound environment reproduction processing of original sound field in reproduced sound field]
Next, a description will be given of a process for reproducing the acoustic environment in the passenger compartment that is the original sound field in the laboratory that is the reproduced sound field. The reproduction of the acoustic environment of the original sound field in the reproduced sound field is realized by a sound field reproduction system.

  FIG. 7 is a block diagram showing a schematic configuration of the sound field reproduction system 1. As shown in FIG. 7, the sound field reproduction system 1 includes a speaker unit (first output means) 22 installed in a laboratory that is a reproduced sound field 21, and a sound output device that outputs sound to the speaker unit 22. 4, a computer (sound processing means) 40 that outputs an evaluation sound to the sound output device 4, an audio device (sound reproduction means) 41 that can output a multi-channel sound signal, and an audio device 41. The audio input device 8 outputs a sound signal to be reproduced to the computer 40.

  Here, the audio output device 4 used in the sound field reproduction system 1, the audio input device 8, and the speaker unit 22 are the audio output device 4 used in the reproduction sound field acoustic system 20, the audio input device 8, Since it is the same structure as the speaker part 22 and is provided with the same function, the detailed description is abbreviate | omitted.

  The audio device 41 is a device that reads out music information recorded on a recording medium such as a CD (Compact Disc), a DVD, or an MD (MiniDisc) and outputs it as an acoustic signal. The audio device 41 can output a multi-channel sound signal. For example, a multi-channel sound such as a 5.1-channel sound signal recorded on a DVD can be reproduced. . In the present embodiment, for example, a case where a 4-channel acoustic signal recorded on a recording medium is output will be described.

  The acoustic signal output here is an acoustic signal corresponding to each speaker FR, FL, RR, RL of the speaker unit 3 installed in the original sound field 6, and each channel generates a sound emitted from the front right side of the listener. An acoustic signal S (FR) mainly including a sound signal S (FL) mainly including a sound emitted from the front left side of the listener, and an acoustic signal S (RR) mainly including a sound emitted from the rear right side of the listener; The sound signal S (RL) mainly includes sound emitted from the left side of the listener.

  The computer 40 acquires a multi-channel acoustic signal reproduced by the audio device 41 via the audio input device 8, and performs an acoustic process on the acquired acoustic signal to thereby output an acoustic signal output in the reproduction sound field 21. In addition, it has a role of processing so as to have the same acoustic characteristics as the acoustic signal output in the original sound field 6.

  The computer 40 is roughly configured by a control unit (acoustic control unit) 42, a convolution operation processing unit (acoustic control unit) 43, and a sound field reproduction filter recording unit (acoustic reproduction information recording unit) 44. The sound field reproduction filter recording unit 44 records the sound field reproduction filter calculated by the filter calculation device 30 described above. The sound field reproduction filter recording unit 44 is configured by a general recording device.

The convolution operation processing unit 43 uses a sound field reproduction filter recorded in the sound field reproduction filter recording unit 44 for a multi-channel acoustic signal input by the voice input device 8 in accordance with a control command of the control unit 42. The convolution operation processing is performed, and the sound processing is performed on the sound signals output from the N speakers 23 of the speaker unit 22. Specifically, as shown in FIG. 8, a 4-channel multi-channel sound source (acoustic signal S (FR), acoustic signal S (FL), acoustic signal S (RR), acoustic signal S) input from the audio device 41 is used. (RL)) is performed by the convolution operation processing unit 43 for each channel, corresponding to the sound field reproduction filter (sound field reproduction filter Q _j (FR), sound field reproduction filter Q _j (FL), sound field reproduction). Convolution calculation processing 46 to 49 using any one of the filter Q _j (RR) and the sound field reproduction filter Q _j (RL) is performed.

  The acoustic signals of each channel subjected to the convolution operation are added by the adder K1 to the adder KN for each sound output of the same channel subjected to the convolution operation by the respective sound field reproduction filters, and N corresponding to the number of speakers in the reproduction sound field. Acoustic processing is performed on an acoustic signal as individual channel components. Then, the convolution operation processing unit 43 outputs an acoustic signal having N multi-channel components from the control unit 42 to the audio output device 4, and the audio output device 4 generates an acoustic signal from the speaker 23 corresponding to each channel. A signal is output from each speaker 23 so as to be output.

As described above, in the sound field reproduction system 1 according to the present embodiment, the convolution operation processing unit 43 receives the multi-channel acoustic signal input from the audio device 41 via the audio input device 8 to each channel. Using the corresponding sound field reproduction filters Q _j (FR), Q _j (FL), Q _j (RR), Q _j (RL), acoustic processing can be performed for each channel. For this reason, even when a multi-channel acoustic signal is reproduced by the audio device 41, the acoustic processing corresponding to each channel is performed using the sound field reproduction filters Q _j (FR), Q _j (FL), Q _j ( RR), Q _j (RL) can be applied, and the acoustic characteristics of the original sound field 6 that can reproduce the multi-channel acoustic signal can be obtained by using the multi-channel acoustic signal in the reproduction sound field 21. It can be reproduced.

  As described above, since the sound processing corresponding to the multi-channel sound signal can be performed in the reproduction sound field 21, it becomes possible to perform the sound source adjustment processing independent for each channel, and in the audio device, the sound effect or Even when the gain / delay processing is performed, the acoustic effect and the like can be effectively and faithfully reflected in the reproduced sound field 21.

  Further, in the sound field reproduction system 1 according to the present embodiment, as shown in FIG. 8, after performing the convolution operation of the corresponding sound field reproduction filter on the output sound of each channel, the acoustic signal of each channel is obtained. Since the sound signal is output from the speakers (N speakers) 23 of the speaker unit 22 by adding, the sound signal of a specific channel is emphasized / weakly adjusted by selecting / controlling the channel to be added. And so on. In addition, various sound fields can be reproduced by arbitrarily selecting combinations of channels to be added.

  While the sound field reproduction system according to the present invention has been described in detail with reference to the drawings, the sound field reproduction system according to the present invention is not limited to the above-described embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, in the above-described embodiment, after the sound field reproduction filter is calculated by the filter calculation device 30, the calculated sound field reproduction filter is recorded in the sound field reproduction filter recording unit 44, and the convolution calculation processing unit 43 performs the convolution calculation. Although it was the structure to perform, the structure which performs calculation of a sound field reproduction filter in the sound field reproduction system 1 may be sufficient.

  FIG. 9 shows a sound field reproduction system 57 capable of performing a sound field reproduction filter calculation process by causing the control unit 56 of the computer 55 to process the function of the filter calculation processing unit 31 in the filter calculation device 30. FIG.

  In the sound field reproduction system 57 shown in FIG. 9, compared to the sound field reproduction system 1 (see FIG. 7) described in the embodiment, an original sound field characteristic recording unit 32 and a reproduction sound field characteristic recording unit are included in the computer 55. 33 in that it is provided.

  In the sound field reproduction system 57, the control unit 56 calculates a sound field reproduction filter based on the acoustic characteristics recorded in the original sound field characteristic recording unit 32 and the acoustic characteristics recorded in the reproduced sound field characteristic recording unit 33. The calculated sound field reproduction filter is recorded in the sound field reproduction filter recording unit 44. Then, the control unit 56 causes the convolution operation processing unit 43 to perform convolution operation processing on the input multi-channel acoustic signal using the sound field reproduction filter recorded in the sound field reproduction filter recording unit 44. Thus, acoustic processing is performed on the acoustic signals output from the N speakers 23 of the speaker unit 22.

  As described above, in the sound field reproduction system 57, by performing the calculation process of the sound field reproduction filter, it is not necessary to separately provide the filter calculation device 30, so that the system configuration can be simplified. In addition, by causing the sound field reproduction system 57 to perform the calculation process of the sound field reproduction filter, it is possible to facilitate and speed up the process.

It is a block diagram which shows schematic structure of the original sound field acoustic system which concerns on embodiment. It is the flowchart which showed the acoustic characteristic measurement process of the original sound field by the control part which concerns on embodiment. It is a block diagram which shows schematic structure of the reproduction sound field acoustic system which concerns on embodiment. It is the flowchart which showed the acoustic characteristic measurement process of the reproduction sound field by the control part which concerns on embodiment. It is a block diagram which shows schematic structure of the filter calculation apparatus which concerns on embodiment. It is the flowchart which showed the calculation process of the sound field reproduction filter by the filter calculation process part which concerns on embodiment. It is a block diagram which shows schematic structure of the sound field reproduction system which concerns on embodiment. It is explanatory drawing for demonstrating the convolution calculation process by the convolution calculation process part which concerns on embodiment. It is a block diagram which shows the other schematic structural example of the sound field reproduction system which concerns on embodiment.

Explanation of symbols

1, 57 ... Sound field reproduction system 2 ... Original sound field acoustic system 3 ... (Original sound field) speaker unit (second output means)
4 ... Audio output device 5, 40, 55 ... Computer (acoustic processing means)
6 ... Original sound field 7 ... Microphone array (sound collecting means)
DESCRIPTION OF SYMBOLS 8 ... Voice input device 10 ... Vehicle 12 ... Microphone 13 (of microphone array) ... Driver's seat 15 ... Evaluation sound generation part 16 ... Impulse response calculation part 17 ... Impulse response recording part 18, 42, 56 ... Control part (acoustic control means) )
20 ... Reproduced sound field acoustic system 21 ... Reproduced sound field 22 ... (Reproduced sound field) speaker unit (first output means)
23 ... Speaker 30 ... Filter calculation device 31 ... Filter calculation processing section (acoustic reproduction information calculation means)
32 ... Original sound field characteristic recording section (original sound field characteristic recording means)
33. Reproduced sound field characteristic recording unit (reproduced sound field characteristic recording means)
34 ... Filter information recording unit 41 ... Audio equipment (sound reproduction means)
43 ... Convolution calculation processing part (acoustic control means)
44 ... Sound field reproduction filter recording unit (acoustic reproduction information recording means)
46 to 49 ... convolution calculation processing A _ij ... acoustic characteristics D _j (for reproduced sound field) acoustic characteristics FL (for original sound field) front left speaker FR ... front right speakers K1 to KN ... adder Q _j ... sound field reproduction Filter RL ... Rear left speaker RR ... Rear right speaker S (FR), S (FL), S (RR), S (RL) ... Acoustic signal

Claims (4)

Sound reproducing means capable of reproducing sound signals having multi-channel sound information;
First output means capable of outputting the sound signal reproduced by the sound reproduction means from a plurality of speakers according to the multi-channel sound information;
Sound processing means for performing sound processing on the sound signal reproduced by the sound reproduction means and outputting from the first output means; and
The acoustic processing means includes
The acoustic characteristics for each speaker of the first output means in the reproduced sound field where the first output means is installed and the acoustic characteristics for each speaker in the original sound field where the second output means having a plurality of speakers are installed An acoustic reproduction information recording means for recording, for each speaker of the second output means, a sound field reproduction filter capable of reproducing the acoustic characteristics of the original sound field in the reproduced sound field,
The sound field reproduction filter of the speaker corresponding to the channel of the sound signal is convolved with the multi-channel sound signal reproduced by the sound reproducing means, and the sound signal subjected to the convolution operation is added for each speaker component. And a sound control means for outputting to each speaker of the first output means according to a channel of the sound signal. The acoustic characteristics for each speaker of the first output means in the reproduction sound field are obtained by collecting the evaluation sound output for each speaker by the first output means for each speaker by the sound collection means installed in the reproduction sound field. The sound field reproduction system according to claim 1, wherein the sound field reproduction system is calculated based on the recorded sound. The acoustic characteristics for each speaker of the second output means in the original sound field are obtained by collecting the evaluation sound output for each speaker in the second output means for each speaker by the sound collecting means installed in the original sound field. The sound field reproduction system according to claim 1, wherein the sound field reproduction system is calculated based on recorded sound. The acoustic processing means includes
Original sound field characteristic recording means for recording acoustic characteristics of each of the speakers of the second output means in the original sound field;
Reproduced sound field characteristic recording means for recording acoustic characteristics of each speaker of the first output means in the reproduced sound field;
The sound for calculating the sound field reproduction filter based on the acoustic characteristics of the reproduced sound field recorded in the original sound field characteristic recording means and the acoustic characteristics of the original sound field recorded in the reproduced sound field characteristic recording means. A sound field reproduction system comprising: reproduction information calculation means.

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