JP2023054301A - Sound control device, sound control method and sound control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound control device that can appropriately perform frequency characteristic adjustment or the like to perform sound emission of music while removing acoustic influence in an in-vehicle space.

SOLUTION: A sound control device comprises: a frequency characteristics analyzing section 1 that determines whether or not an adjustment value which is used for adjustment of frequency characteristics of sound data in performing sound emission is updated on the basis of at least one of sound data corresponding to sound to be emitted and sound collection data corresponding to the sound collected by a microphone MC that collects sound in an in-vehicle space where the sound is emitted; and an equalizer value setting section 2 that updates the adjustment value when it is determined that the updating is performed, and causes the sound corresponding to the sound data, in which the frequency characteristics is adjusted, to emit from a speaker SP using the adjustment value after the updating.

SELECTED DRAWING: Figure 2

COPYRIGHT: (C)2023,JPO&INPIT

Description

The present application belongs to the technical field of a sound control device, a sound control method, and a sound control program. More specifically, it belongs to the technical field of a sound control device and a sound control method for controlling a sound adjustment mode, and a sound control program used in the sound control device.

For example, an audio device is installed in a vehicle to enjoy music while moving. Here, the acoustic characteristics due to the shape of the interior space of the vehicle (hereinafter, the interior space is simply referred to as the “interior space”) vary depending on the vehicle type, the number of passengers on board, the position of the passenger, or It changes each time due to the influence of sounds caused by the movement environment (for example, so-called wind noise, road noise, or sounds caused by weather conditions such as rain). Therefore, in order to enjoy music that corresponds to the original sound even if the acoustic characteristics change, it is necessary to correct the frequency characteristics, etc., when the original sound is emitted into the vehicle interior space so as to correspond to the acoustic characteristics of the vehicle interior space. It is necessary to make adjustments including Conventionally, when making adjustments that include such corrections, a predetermined test sound is emitted into the vehicle interior while the vehicle is stopped, and its acoustic characteristics are evaluated. . However, in this case, adjustment including correction reflecting the moving environment of the vehicle, the boarding position of the passenger, and the like cannot be performed. Therefore, it is being considered to perform adjustments including correction of the above-described frequency characteristics using music emitted in the vehicle interior space while the vehicle is moving. As an example of prior art related to such studies, there is a technique described in Patent Literature 1 below, for example. The technique described in Patent Document 1 is configured to correct and adjust the frequency characteristics and the like of the music emitted while the vehicle is moving.

JP-A-5-299957

However, when the technique described in Patent Document 1 is used, for example, when the influence of the moving environment is large, or when the frequency characteristics of the original sound to be emitted are biased, correction of such problems may occur. There is a problem that the adjustment including the correction cannot be properly performed if the predetermined measurement conditions for the adjustment including the correction are not provided.

Therefore, the present application has been made in view of the above problems, and one example of the problem is to emit music by appropriately adjusting the frequency characteristics etc. while eliminating the acoustic influence in the above-mentioned interior space. It is an object of the present invention to provide a sound control device, a sound control method, and a sound control program used for the sound control device, which can control the sound.

In order to solve the above-mentioned problems, the invention described in claim 1 provides original sound information corresponding to the original sound to be emitted, and sound collecting means for collecting the sound of the space from which the original sound is emitted. Based on at least one of collected sound information corresponding to the collected sound, whether to perform an update process of updating an adjustment value used for adjusting the frequency characteristics of the original sound information when emitting the original sound determining means for determining whether or not to perform the update processing, updating the adjustment value when it is determined to perform the update processing, and using the updated adjustment value to correspond to the original sound information in which the frequency characteristic has been adjusted and updating means for emitting the original sound from the sound emitting means.

In order to solve the above problems, the invention according to claim 9 provides speed information acquisition means for acquiring speed information indicating a moving speed in a space in which the original sound is emitted, and based on the acquired speed information, a determination means for determining whether or not to perform an update process for updating an adjustment value used for adjusting the frequency characteristics of the original sound information corresponding to the original sound when the original sound is emitted; and determining to perform the update process. updating means for updating the adjustment value when the adjustment value is adjusted, and causing the sound emitting means to emit the original sound corresponding to the original sound information whose frequency characteristics have been adjusted using the updated adjustment value.

In order to solve the above-mentioned problems, the invention according to claim 10 provides a sound control method that is executed in a sound control device that includes determination means and update means and is connected to sound collection means and sound emission means. at least one of original sound information corresponding to the original sound to be emitted and collected sound information corresponding to the sound collected by the sound collecting means for collecting the sound in the space where the original sound is emitted a determination step of determining, by the determination means, whether or not to perform an update process of updating an adjustment value used for adjusting the frequency characteristics of the original sound information when emitting the original sound, based on one of the above; updating the adjustment value by the updating means when it is determined that the processing is to be performed, and emitting the original sound corresponding to the original sound information whose frequency characteristics have been adjusted using the updated adjustment value from the sound emitting means; and an updating step of emitting sound.

In order to solve the above problems, the invention according to claim 11 provides a computer connected to the sound collecting means and the sound emitting means, the sound control device according to any one of claims 1 to 9. configured to function as

1 is a block diagram showing a schematic configuration of a sound control device according to an embodiment; FIG. 1 is a block diagram showing a schematic configuration of a sound field adjustment device according to an embodiment; FIG. 6 is a flowchart showing sound field adjustment processing according to the embodiment; FIG. 4 is a conceptual diagram illustrating details of sound field adjustment processing according to an embodiment;

Next, the form for implementing this application is demonstrated using FIG. Note that FIG. 1 is a block diagram showing a schematic configuration of the sound control device according to the embodiment.

As shown in FIG. 1, the sound control device S according to the embodiment includes a determination means 1 connected to a sound collecting means MC such as a microphone, and an updating means 2 connected to a sound emitting means SP such as a speaker. configured with.

In this configuration, the determination means 1 corresponds to the original sound information corresponding to the original sound to be emitted, and the sound collected by the sound collecting means MC for collecting the sound of the space where the original sound is emitted. Based on at least one of the collected sound information, it is determined whether or not to perform update processing for updating adjustment values used for adjusting the frequency characteristics of the original sound information when emitting the original sound.

The updating means 2 updates the adjustment value when it is determined that the update processing is to be performed, and emits the original sound corresponding to the original sound information whose frequency characteristics have been adjusted using the updated adjustment value. A sound is emitted from the sound means SP.

As described above, according to the operation of the sound control device S according to the embodiment, based on at least one of the original sound information and the collected sound information, the frequency characteristics of the original sound information when emitting the original sound can be changed. Since it is determined whether or not to update the adjustment value used for adjustment, it is possible to adjust the frequency characteristics of the original sound information while eliminating the influence of the space where the original sound is emitted based on the collected sound information. It can be made to go properly and emit sound.

Next, specific examples corresponding to the above-described embodiments will be described with reference to FIGS. 2 to 4. FIG. In the embodiment described below, when reproducing sound such as music from a car audio device mounted in a vehicle, the shape of the interior space of the vehicle, the number and positions of passengers, or disturbances that occur during movement An embodiment in which the present invention is applied to a sound field adjustment device that sets a frequency characteristic adjustment value corresponding to the influence of sound and adjusts the frequency characteristics of sound data corresponding to the reproduced sound according to the frequency characteristic adjustment value. be. At this time, the disturbance sound includes, for example, road noise, wind noise, and engine sound generated during movement, and sound caused by weather conditions such as the rain sound. Further, the "frequency characteristic adjustment value" is an adjustment value for realizing so-called equalizer characteristics, and more specifically, an adjustment value for adjusting the sound pressure for each frequency band of the sound data. Furthermore, the vehicle interior space corresponds to an example of the "space" according to the present application.

2 is a block diagram showing a schematic configuration of the sound field adjusting device according to the embodiment, FIG. 3 is a flow chart showing sound field adjustment processing according to the embodiment, and FIG. 4 is a sound field adjustment according to the embodiment. FIG. 3 is a conceptual diagram for explaining details of processing; At this time, in FIG. 2, the same member numbers as the respective structural members of the sound control device S are used for the respective structural members of the embodiment corresponding to the respective structural members of the sound control device S according to the embodiment shown in FIG. ing.

As shown in FIG. 2, the sound field adjustment device SS according to the embodiment includes a smartphone SM in which sound data of the above-mentioned sound to be reproduced is recorded in various file formats, and a sound emitting means SP as an example of the embodiment. , and the car audio device 16 connected to the speaker SP. A so-called music player may be connected instead of the smartphone SM. The sound field adjustment device SS according to the embodiment includes a microphone MC as an example of the sound collecting means MC according to the embodiment, a frequency characteristic analysis section 1 as an example of the determination means 1 according to the embodiment, An equalizer value setting unit 2 as an example of updating means 2, a communication unit 10 connected to the smartphone SM by wire or wirelessly, an audio decoder 11, an acceleration sensor 12, a frequency characteristic adjustment unit 13, and an audio encoder 14. and a communication unit 15 connected to the car audio device 16 by wire or wirelessly. At this time, the frequency characteristic analysis section 1, the equalizer value setting section 2, the audio decoder 11, the frequency characteristic adjustment section 13, and the audio encoder 14 are connected to a CPU, RAM (not shown) provided in the sound field adjustment device SS. Random Access Memory) and ROM (Read Only Memory). etc., and read out and executed by the CPU or the like to be realized in software. 2, the frequency characteristic analysis unit 1 and the equalizer value setting unit 2 constitute an example of the sound control device S according to the embodiment. Furthermore, the frequency characteristic analysis unit 1 corresponds to an example of the "speed information acquisition means" and the "sound emission determination means" according to the present application.

In the above configuration, sound data such as music to be played back is pre-recorded in the smartphone SM as described above. Output to the unit 10 . This music to be played corresponds to an example of the "original sound" according to the present application. Accordingly, the communication unit 10 performs preset input interface processing on the sound data input from the smartphone SM, and outputs the processed data to the audio decoder 11 . Then, the audio decoder 11 performs decoding processing based on a preset decoding method on the output sound data, and obtains sound in a format capable of detecting sound pressure for each predetermined frequency band as the frequency characteristic. It is output to the frequency characteristic analysis section 1 and the frequency characteristic adjustment section 13 as data (for example, PCM (Pulse Code Modulation) format sound data).

On the other hand, the acceleration sensor 12 detects the magnitude and direction of acceleration applied to the vehicle on which the sound field adjustment device SS is mounted, generates acceleration data indicating the detected acceleration, and outputs the data to the frequency characteristic analysis unit 1. do. The acceleration data is integrated in the frequency characteristic analysis unit 1 as will be described later, converted into speed data indicating the speed of the vehicle, and subjected to sound field adjustment processing according to the embodiment. At this time, the acceleration data may be integrated by the acceleration sensor 12 itself and output to the frequency characteristic analysis section 1 as the velocity data. On the other hand, the microphone MC collects sound in the vehicle interior space of the vehicle in which the sound field adjustment device SS is mounted, and collects sound data in a format that can detect the sound pressure for each predetermined frequency band as the frequency characteristic. , is output to the frequency characteristic analysis unit 1. Sounds collected by the microphone MC include sounds such as music emitted from the speaker SP according to the embodiment as described later, as well as the above-described disturbance sounds generated when the vehicle is moving. ing.

Next, the frequency characteristic analysis unit 1 analyzes the sound data according to the embodiment based on the sound data from the audio decoder 11, the velocity data corresponding to the acceleration data detected by the acceleration sensor 12, and the collected sound data from the microphone MC. It mainly executes frequency characteristic analysis processing in the field adjustment processing. At this time, if the acceleration data is output from the acceleration sensor 12, the frequency characteristic analysis unit 1 integrates the acceleration data to generate the velocity data for the frequency characteristic analysis process. Then, the result of the frequency characteristic analysis processing is output to the equalizer value setting section 2 . As a result, the equalizer value setting unit 2 determines the frequency characteristics (that is, the sound pressure for each predetermined frequency band) of the sound data emitted through the speaker SP based on the result of the frequency characteristics analysis process. A correction value in the sound field adjustment process according to the embodiment for updating the frequency characteristic adjustment value used for adjustment is set and output to the frequency characteristic adjustment unit 13 .

On the other hand, the frequency characteristic adjustment unit 13 adjusts the original size and shape of the vehicle interior space when the vehicle is stopped (that is, the vehicle interior space in a state where no passengers are on board and no luggage is loaded). size and shape), and emits sound into the car space for each type of music to be played (for example, types such as "rock," "classic," or "pops") (that is, for each type). The frequency characteristic data indicating the frequency characteristic as the optimum sound data (hereinafter referred to as "type-specific frequency characteristic data") is stored in advance in a memory (not shown). The type-specific frequency characteristic data is, for example, frequency characteristic data corresponding to the frequency characteristic adjustment value previously selected or set by the user for each type of music. In addition, frequency characteristic adjustment values arbitrarily set by the user regardless of the type of music, the size of the vehicle, etc. may be stored in advance in the memory (not shown).

Then, when the correction value is not output from the equalizer value setting unit 2, the frequency characteristic adjustment unit 13 uses the frequency characteristic data by type corresponding to the sound data output from the audio decoder 11 to adjust the sound data. The frequency characteristics are adjusted, and the sound data whose frequency characteristics have been adjusted is output to the audio encoder 14 . On the other hand, when the correction value is output from the equalizer value setting unit 2, the frequency characteristic adjusting unit 13 adjusts the above-described type-by-type corresponding to the sound data output from the audio decoder 11 while the output is continued. The frequency characteristic adjustment value of the frequency characteristic data is updated using the correction value from the equalizer value setting unit 2, and the sound data whose frequency characteristic is adjusted using the updated frequency characteristic adjustment value is sent to the audio encoder 14. output to

After that, the audio encoder 14 performs encoding processing in an encoding format corresponding to the decoding format of the decoding processing in the audio decoder 11 on the sound data output from the frequency characteristic adjustment unit 13, and Sound data is output to the communication unit 15 . The communication unit 15 performs preset output interface processing on the encoded sound data output from the audio encoder 14 and outputs the result to the car audio device 16 . As a result, the car audio device 16 performs preset amplification processing or the like on the encoded sound data, and emits sound into the vehicle interior space via the speaker SP.

Next, the sound field adjustment processing according to the embodiment will be described more specifically with reference to FIGS. 2 to 4. FIG.

As the corresponding flowchart is shown in FIG. 3, the sound field adjustment process according to the embodiment is performed, for example, by turning on a so-called ACC (Accessory) switch of a vehicle equipped with the sound field adjustment device SS according to the embodiment. and so on.

When the sound field adjustment process according to the embodiment is started, first, the frequency characteristic analysis unit 1 detects sound data whose frequency characteristic is to be adjusted (that is, sound data such as music to be reproduced at that time) from the smartphone SM. (step S1). More specifically, the frequency characteristic analysis unit 1 detects, for example, the operation content of the smartphone SM or the selection operation of the reproduction target in the car audio device 16, and based on the detection result, the sound data to be reproduced is the frequency characteristic. It is determined whether or not the data has been input to the analysis unit 1 . If it is determined in step S1 that sound data to be reproduced has not been input to the frequency characteristic analysis section 1 (step S1: NO), the frequency characteristic analysis section 1 proceeds to step S9, which will be described later. This step S1 is performed on sound data whose frequency characteristics are not subject to adjustment (for example, when it is selected to reproduce sound data received via radio broadcasting in the car audio device 16). The sound field adjustment process according to the example is prevented from being performed.

On the other hand, if the sound data to be reproduced has been input to the frequency characteristic analysis unit 1 in the determination in step S1 (step S1: YES), the frequency characteristic analysis unit 1 next determines the frequency characteristic of the input sound data. is analyzed, and the analysis result is temporarily stored in the RAM or the like (step S2). Then, the frequency characteristic analysis unit 1 determines whether or not the frequency characteristic analyzed in step S2 is suitable for performing the sound field adjustment process according to the embodiment (step S3). Specifically, in step S3, the frequency characteristic analysis unit 1, for example, determines whether or not the frequency characteristic analyzed in step S2 is equal to or greater than a preset sound pressure threshold over the entire audible frequency band. If the characteristic is equal to or greater than the sound pressure threshold over the entire area, it is determined that the frequency characteristic is appropriate. Alternatively, the frequency characteristic analysis unit 1 determines whether or not the frequency characteristic analyzed in step S2 is biased in a specific frequency band, and determines that the frequency characteristic is appropriate when there is no bias.

If it is determined in step S3 that the frequency characteristics analyzed in step S2 are not suitable for performing the sound field adjustment process according to the embodiment (step S3: NO), the frequency characteristic analysis unit 1 advances to step S9, which will be described later. Transition. On the other hand, if it is determined in step S3 that the frequency characteristics analyzed in step S2 are suitable for performing the sound field adjustment process according to the embodiment (step S3: YES), the frequency characteristic analysis unit 1 next: The collected sound data is obtained from the microphone MC (step S4), and the correlation coefficient γ between the frequency characteristics of the obtained collected sound data and the frequency characteristics of the sound data is calculated (step S5).

はパラメータｘの平均値であり、

はパラメータｙの平均値である。 Here, the correlation coefficient γ calculated in step S5 is, for example, the sound pressure as the frequency characteristic of the sound data in each target frequency band is set as "parameter x", and the above-mentioned When the sound pressure as the frequency characteristic of collected sound data is set as "parameter y", the correlation coefficient γ is given by the following equation (1). In the following equation (1), “S _xy ” is the covariance of parameter x and parameter y, “S _x ” is the standard deviation of parameter x, and “S _y ” is the standard deviation of parameter y. . Also, "n" is the total number of pairs of parameter x and parameter y for the same frequency band (i.e., the number of divided frequency bands), and " _xi " is the individual sound pressure as parameter x. , “y _i ” is the individual sound pressure as parameter y, and

is the mean value of the parameter x, and

is the average value of the parameter y.

Here, details of the correlation coefficient γ defined by the above equation (1) can be found, for example, at the URL “https://sci-pursuit.com/math/statistics/correlation-coefficient.html” on the Internet. When the correlation coefficient γ is equal to or greater than a preset correlation threshold, the parameter x (that is, the sound pressure as the frequency characteristic of the sound data) and the parameter y (that is, the sound pressure as the frequency characteristic of the collected sound data) ), there is a correlation between When this is applied to the sound field adjustment process according to the embodiment, the presence of the correlation means that the collected sound data "has a volume suitable for the sound field adjustment process according to the embodiment" and "the disturbance sound The noise is not so large as to interfere with the sound field adjustment process.

Therefore, the frequency characteristic analysis unit 1 determines whether or not the correlation coefficient γ calculated in step S5 is equal to or greater than the correlation threshold (step S6). If the calculated correlation coefficient γ is less than the correlation threshold (step S6: NO) in step S6, the frequency characteristic analysis unit 1 proceeds to step S9, which will be described later. On the other hand, in the determination in step S6, if the calculated correlation coefficient γ is equal to or greater than the correlation threshold (step S6: YES), the frequency characteristic analysis unit 1 next performs acceleration detected by the acceleration sensor 12 or It is determined whether or not the corresponding speed is greater than or equal to a preset speed threshold (step S7). Here, as a specific example of the speed threshold, for example, when the sound field adjustment process according to the embodiment is performed while the vehicle equipped with the sound field adjustment device SS according to the embodiment is not running. , the speed threshold is, for example, 5 kilometers per hour. Further, when the sound field adjustment process according to the embodiment is to be performed in a state in which the above-described external noise such as road noise is low when the vehicle is traveling at low speed, the speed threshold is set to, for example, 30 kilometers per hour. . When the acceleration data is output from the acceleration sensor 12, the frequency characteristic analysis unit 1 integrates it and uses it for determination in step S7. If so, the speed data is directly used for determination in step S7. In this step S7, when the speed of the vehicle equipped with the sound field adjustment device SS is higher than the speed threshold, it is predicted that the disturbance noise is loud, so the sound field adjustment processing according to the embodiment is not performed. It is a judgment for making In the judgment of step S7, if the speed of the vehicle is greater than the speed threshold (step S7: NO), the frequency characteristic analysis unit 1 proceeds to step S9, which will be described later. On the other hand, if it is determined in step S7 that the speed of the vehicle is equal to or less than the speed threshold (step S7: YES), the frequency characteristic analysis unit 1 sets the frequency characteristic data of the sound data and the collected sound data to an equalizer value. Output to part 2.

Next, the equalizer value setting unit 2 outputs from the audio decoder 11 the condition for performing the sound field adjustment processing according to the embodiment (see the above steps S1, S3, S6 and S7). The correction value for updating the frequency characteristic adjustment value of the type-specific frequency characteristic data corresponding to the sound data is calculated (step S8).

Here, calculation of the correction value in step S8 will be specifically described using FIG. First, in step S7, frequency characteristic data as sound data (see step S2) having frequency characteristics shown in FIG. 4 and frequency characteristic data as collected sound data having frequency characteristics shown in FIG. , is output. Here, the frequency characteristics of the collected sound data include the frequency characteristics of the original sound data itself and the original frequency characteristics of the vehicle interior space where the sound corresponding to the sound data is emitted (that is, when the vehicle is stopped). (Frequency characteristics corresponding to the size and shape of the interior space of the vehicle when no passengers are on board and no luggage is loaded), and the sound corresponding to the sound data is actually emitted. (i.e., the frequency characteristics of the interior space when passengers are on board, luggage is loaded, and there is the above-mentioned disturbance sound). become. Therefore, in step S8, the equalizer value setting unit 2 performs a process of subtracting the frequency characteristics of the sound data from the frequency characteristics of the collected sound data for each predetermined frequency band, and calculates the difference data as a result of the subtraction process. Calculate (see bottom of FIG. 4). In the lower part of FIG. 4, the upper difference for each frequency band is indicated by a dashed line, and the frequency at which the difference is zero is indicated by a one-dot chain line arrow. The frequency characteristic corresponding to this difference data includes frequency characteristic data by type used when the sound data of the frequency characteristic shown in FIG. characteristic data"), the original frequency characteristic of the vehicle interior space, and the frequency characteristic of the vehicle interior space when the sound corresponding to the sound data is actually emitted. At least it is reflected. After that, the equalizer value setting unit 2 updates the frequency characteristic adjustment value of the sound emission type-specific frequency characteristic data so that the frequency characteristic as the difference data becomes the frequency characteristic indicated by the sound emission type-specific frequency characteristic data. Calculate the above correction value for More specifically, for example, when the type corresponding to the type-specific frequency characteristic data set at that time (that is, the sound emission type-specific frequency characteristic data) is "lock", the equalizer value setting unit 2 performs the operation shown in FIG. The update correction value is calculated so that the frequency characteristic as the difference data shown below becomes the frequency characteristic indicated by the frequency characteristic adjustment value of the frequency characteristic data for each type for locking. By correcting the frequency characteristic data by sound emission type by updating using this correction value for updating, as a result, the frequency as the vehicle interior space when the sound corresponding to the above sound data is actually emitted The influence of the characteristics (that is, the original frequency characteristics of the vehicle interior space and the frequency characteristics of the vehicle interior space when the sound corresponding to the sound data is actually emitted) can be eliminated. After that, the equalizer value setting section 2 outputs the calculated correction value to the frequency characteristic adjusting section 13 .

As a result, the frequency characteristic adjustment unit 13, as described above, when the correction value is not output from the equalizer value setting unit 2 (FIG. 3 step S1: NO, step S3: NO, step S6: NO, or In the case of step S7: NO), the frequency characteristic data by type corresponding to the sound data output from the audio decoder 11 (that is, the original frequency characteristic data by type whose frequency characteristic adjustment value is not updated) is used. The frequency characteristics of the sound data are adjusted, and the sound data whose frequency characteristics have been adjusted are output to the audio encoder 14 (step S9). On the other hand, when the correction value for update is output from the equalizer value setting unit 2, while the output is continued, the frequency characteristic adjustment unit 13 adjusts the frequency characteristic adjustment value of the type-specific frequency characteristic data. , update using the correction value from the equalizer value setting unit 2, and output sound data whose frequency characteristics have been adjusted using the updated correction value to the audio encoder 14 (step S9).

After that, the sound field adjustment device SS performs sound field adjustment processing according to the embodiment by, for example, detecting that the ACC switch of the vehicle in which the sound field adjustment device SS according to the embodiment is mounted is turned off. It is determined whether or not to end (step S10). When it is determined in step S10 that the sound field adjustment process according to the embodiment is to be continued (step S10: NO), the sound field adjustment device SS returns to step S1 and repeats the processes described above. On the other hand, when the sound field adjustment process according to the embodiment is to be ended in the determination of step S10 (step S10: YES), the sound field adjustment device SS ends the sound field adjustment process as it is.

As described above, according to the sound field adjustment processing according to the embodiment, based on at least one of the sound data of the sound emitted into the vehicle interior space and the collected sound data, the It is determined whether or not to update the adjustment value used for adjusting the frequency characteristics of the sound data (see steps S8 and S9 in FIG. 3) (see steps S1, S3, S6 and S7 in FIG. 3). ), it is possible to appropriately adjust the frequency characteristics of the sound data and emit sound while eliminating the influence of the vehicle interior space based on the collected sound data and the like. Note that, according to the sound field adjustment processing according to the embodiment, as a result, not only the influence of the above-mentioned interior space but also the influence of the acoustic circuit itself included in the car audio device 16, the structure of the speaker SP, etc., on the frequency characteristics. can also be eliminated.

Further, since the update is a process of updating the frequency characteristic adjustment value corresponding to the original type-specific frequency characteristic data so that the frequency characteristic of the collected sound data becomes the frequency characteristic indicated by the type-specific frequency characteristic data, The adjustment can be performed more appropriately based on the frequency characteristics of collected sound data.

Furthermore, since the type-specific frequency characteristic data is frequency characteristic data of frequency characteristics selected or set by the user, it is possible to appropriately adjust the frequency characteristics according to the user's preference.

Furthermore, when the frequency characteristics of the sound data are appropriate in the audible frequency band (in other words, when the frequency band is equal to or greater than the predetermined sound pressure threshold; see step S3 in FIG. 3), the update is performed. The frequency characteristics can be adjusted more appropriately.

Further, it is determined whether or not to update based on the correlation coefficient γ corresponding to the degree of similarity between the frequency characteristics of the collected sound data and the frequency characteristics of the sound data (step S5 and See step S6), the frequency characteristic can be adjusted more appropriately.

Furthermore, it is determined whether or not to perform the above update based on the collected sound data acquired when the speed of movement in the vehicle interior space where the sound is emitted is equal to or less than the predetermined speed threshold (see step S7 in FIG. 3). ), and the frequency characteristics can be adjusted more appropriately.

Furthermore, it is determined whether or not to perform the above update using collected sound data acquired when it is indicated that the sound to be reproduced (music, etc.) is being emitted into the vehicle interior space (Fig. 3 (See step S1), the frequency characteristic can be adjusted more appropriately.

In the above-described embodiment, the frequency characteristic adjustment value is made flat over the entire frequency band, and the frequency characteristic adjustment value is updated so that the difference data shown in the lower part of FIG. 4 becomes zero decibel over the entire frequency band. By doing so, the sound to be reproduced can be heard with frequency characteristics corresponding to the original sound.

Further, in the above-described embodiment, the significance of using the correlation coefficient γ is that the collected sound data "has a volume suitable for the sound field adjustment process according to the embodiment" and "the noise such as the disturbance sound is It was decided to use it to determine that the size is not such that it is an obstacle to field adjustment processing. However, if the significance is limited only to "determining that the noise such as the disturbance sound is not of a magnitude that interferes with the sound field adjustment process", the correlation coefficient γ is not used. The determination may be made using only the acceleration data from the acceleration sensor 12, or the correlation coefficient γ may be used to determine whether the noise such as the disturbance sound is of a magnitude that interferes with the sound field adjustment process. The acceleration sensor 12 itself can be made unnecessary by "determining that it is not".

Further, a device (for example, the car audio device 16 according to the embodiment) on the side of the speaker SP when viewed from the sound field adjustment device SS according to the embodiment can switch the sound source of the sound to be reproduced. When information indicating the current sound source cannot be obtained, there is a problem that the sound field adjustment processing according to the embodiment cannot be performed appropriately when a different sound source is being reproduced. By using γ, it is also possible to determine whether or not the sound source of the sound to be played has been switched in the device on the speaker SP side (that is, whether or not the sound such as music to be played is being played). can.

[Modification]
Next, modifications corresponding to the above-described embodiment will be described.

First, as a first modified example, in the above-described embodiment, it is determined whether or not to update the correction value of the frequency characteristic of sound data in steps S1, S3, S6, and S7 shown in FIG. However, in addition to this, whether or not to adjust the frequency characteristic of the sound data itself may be determined by the above step S1 or the like. Even in this case, it is possible to more appropriately adjust the frequency characteristics of the sound data and emit sound while eliminating the influence of the space inside the vehicle.

Next, as a second modification, in the above-described embodiment, step S1, step S3, step S6, and step S7 shown in FIG. 3 are combined to determine whether or not to update the adjustment value. However, in addition to this, the adjustment value is updated or the frequency characteristic is modified based only on the speed data indicating the speed of movement of the vehicle in which the sound field adjustment device SS is mounted (in other words, the interior space of the vehicle). It may be configured to determine whether or not to perform the adjustment itself. Even in this case, it is possible to appropriately adjust the frequency characteristics of the sound data and emit sound while eliminating the influence of movement of the vehicle (in-vehicle space).

As a third modification, in the above-described embodiment, whether or not the frequency characteristic adjustment value is updated using the frequency characteristic as sound data before adjusting the frequency characteristic and the frequency characteristic of the collected sound data In addition to this, the frequency characteristics after adjustment by the frequency characteristics adjustment unit 13 (that is, the frequency characteristics of the sound data immediately after being output from the frequency characteristics adjustment unit 13) and the frequency characteristics of the collected sound data. may be used to determine whether or not to update the frequency characteristic adjustment value or adjust the frequency characteristic itself. This is because the frequency characteristics after adjustment by the frequency characteristics adjustment unit 13 are also the frequency characteristics of the sound data corresponding to the emitted sound. According to the configuration of this third modified example, the frequency characteristics corresponding to the difference data shown in the lower part of FIG. and the frequency characteristics of the vehicle interior space at that time are typically reflected. Therefore, by updating using the correction value according to the embodiment so that the magnitude of the difference data is reduced, the frequency characteristics of the sound emitted into the vehicle interior space can be adjusted to the desired frequency characteristics (as a so-called reference). frequency characteristics).

Furthermore, as a fourth modification, in the above-described embodiment, the car audio device 16 and the smartphone SM as the sound source are connected to the sound field adjustment device SS according to the embodiment. and the function of reproducing the corresponding sound data may be included in the sound field adjustment device. In this case, the communication section 10 and the communication section 15 become unnecessary. By configuring in this way, the embodiment can be applied to existing car audio products (more specifically, car navigation devices, audio devices that can be mounted on vehicles, CD/DVD/BD/USB/tuner-equipped players, etc.). is also applicable.

Furthermore, as a fifth modified example, it is also possible to apply the embodiment to a so-called smart speaker. More specifically, the car audio device 16 and the speaker SP according to the embodiment can be configured to be included in the sound field adjustment device.

As a sixth modification, in the above-described embodiment, sound such as music is played, but in addition to this, the frequency characteristic adjustment value or the correction value according to the embodiment is set for human voice. may In this case, the calculation of the correlation coefficient γ may be performed by limiting the frequency band included in human speech.

Further, as a sixth modified example, in the case where the frequency characteristic adjustment value is not updated in the above-described embodiment (see step S9 in FIG. 3), adjustment is performed while continuing to use the frequency characteristic adjustment value updated in the past. may be performed, or the adjustment itself by the frequency characteristic adjusting unit 13 is not performed (that is, the function of the frequency characteristic adjusting unit 13 is turned off, and the sound data output from the audio decoder 11 is output as is to the audio encoder 14 ( that is, through)).

Furthermore, a program corresponding to the flowchart shown in FIG. 3 is recorded on a recording medium such as an optical disk or hard disk, or obtained via a network such as the Internet, and is read by a general-purpose microcomputer or the like. By executing this, it is possible to cause the microcomputer or the like to function as the CPU of the sound field adjustment device SS according to the embodiment.

1 determination means (frequency characteristic analysis unit)
2 updating means (equalizer value setting unit)
13 Frequency characteristic adjustment unit 16 Car audio device S Sound control device SS Sound field adjustment device SP Sound emission means (speaker)
MC sound collection means (microphone)
SM Smartphone

Claims (1)

At least one of original sound information corresponding to the original sound to be emitted and collected sound information corresponding to the sound collected by the sound collecting means for collecting the sound in the space where the original sound is emitted determining means for determining whether or not to perform update processing for updating an adjustment value used for adjusting the frequency characteristics of the original sound information when emitting the original sound based on the above;
updating the adjustment value when it is determined that the update processing is to be performed, and emitting the original sound corresponding to the original sound information whose frequency characteristics have been adjusted using the updated adjustment value from a sound emitting means; an update means to cause
A sound control device comprising:

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