JP2014195201A - Sound controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound controller that is able to restrain power consumption by adjusting the volume of sound outputted from its speaker depending on the volume of sound outputted from the speaker of another sound controller.SOLUTION: A sound controller comprises a microphone, a speaker, and a communication unit for communicating with another sound controller. A CPU of the sound controller receives a sound signal from the other sound controller via the communication unit (S15). On the basis of a coefficient determined according to a first sound signal corresponding to the received sound signal, the CPU converts the first sound signal to generate a reference signal. If the CPU collected the same sound as that of the first sound signal via the microphone, it obtains a second sound signal, which is a signal of the same sound (S11). The CPU converts the first sound signal to generate an output sound signal (S19) according to a result of comparing the volume of the second sound signal with the volume of the reference signal. The CPU outputs the sound of the generated output sound signal via the speaker (S13).

Description

  The present invention relates to a sound control apparatus capable of performing sound input / output processing and communicating with another sound control apparatus.

  The sound signal collected by the microphone is transmitted via the network to other sound control devices installed at a remote location. At the same time, the remote sound signal is received via the network and the sound is output from the speaker. A sound control device for outputting is known. Such a sound control device is used in a remote conference system or the like. A speakerphone is an example of the sound control device. 2. Description of the Related Art Sound control devices that can connect and use a plurality of sound control devices in the same place are known. In such a sound control device, the audible range of the conference sound and the sound collection range of the uttered sound can be expanded by interspersing the sound control device in a wide area.

  Techniques have been proposed for controlling the volume of sound output from each speaker of a plurality of sound control devices in the same place. For example, Patent Document 1 discloses a technique for changing the volume of a speaker according to the distance between a speaker and the speaker. According to this technique, the sum of the volume of the voice of the speaker and the voice output from the speaker can be made constant at any location.

JP 2006-238254 A

  A case where the user can hear the same sound output from each speaker of a plurality of sound control devices in the same place will be described as an example. If the user can sufficiently recognize the sound output from one speaker, the sound output from the other speaker becomes unnecessary. However, in the technique described in Patent Document 1, although the sum of the volumes of the speech of the speaker and the sound output from the speaker can be made constant, the sum of the volumes of the sound output from each of the plurality of speakers. Cannot be made constant. For this reason, the sound control device may output sound to the user even though the user has sufficiently recognized the sound output from the speaker of another sound control device. The sound control device is desirable because if the user can sufficiently recognize the sound output from the speaker of another sound control device, the current consumption can be suppressed if the volume of the sound output from the speaker can be reduced.

  An object of the present invention is to provide a sound control device capable of suppressing power consumption by adjusting the volume of sound output from a speaker according to the volume of sound output from a speaker of another sound control device. Is to provide.

  A sound control device according to the present invention is a sound control device including a communication unit that communicates with a microphone, a speaker, and another sound control device, and transmits a sound signal that is a signal indicating sound to the communication unit. The first sound signal corresponding to the first sound signal based on a coefficient specified in accordance with the first sound signal corresponding to the sound signal received by the receiving means and the sound signal received by the receiving means. When the same sound as the sound indicated by the first sound signal is collected via the first generation means for generating a reference signal and the microphone, a second sound signal that is a signal of the same sound is acquired. Comparison result between sound volume indicated by the first acquisition means, the second sound signal acquired by the first acquisition means, and the sound volume indicated by the reference signal generated by the first generation means The first sound signal is converted according to the output sound signal A second generating means for generating, and outputting means based on the output sound signal generated by said second generating means, and outputs a sound represented by the output sound signal through the speaker.

  According to the present invention, the sound control device changes the volume of the sound of the first sound signal corresponding to the sound signal received from another sound control device according to the volume of the sound received via the microphone, and outputs the sound. Generate a sound signal. For example, when the sound control device outputs the same sound as the sound indicated by the first sound signal from a speaker of another sound control device and receives this sound through a microphone at a sufficient volume, the sound control device Therefore, the volume of the output sound output from the speaker can be reduced. For example, when the same sound as the sound indicated by the first sound signal is output from a speaker of another sound control device and this sound is received through a microphone at a low volume, the sound is output from the speaker based on the first sound signal. You can increase the volume of the sound you play. In this way, the sound control device can adjust the volume of the output sound output from the speaker in accordance with the volume of the sound output from the speaker of another sound control device. Therefore, the sound control device can suppress the current consumption associated with outputting the output sound from the speaker by suppressing the volume of the output sound output from the speaker. Further, the sound control device can adjust the sound volume at the position of the sound control device to a predetermined level by adjusting the sound volume of the output sound output from the speaker.

  In the present invention, when the volume of the sound indicated by the reference signal is equal to or higher than the volume of the sound indicated by the second sound signal, the second generation means may adjust the volume of the sound indicated by the second sound signal. The output sound signal may be generated by changing the volume of the first sound signal based on a coefficient for increasing to a level approximate to the volume of the sound indicated by the reference signal. As a result, the sound control device can adjust the sound volume output from the speaker so that the sound volume at the position of the sound control device approximates a predetermined level. It can be suppressed efficiently.

  In the present invention, when the volume of the sound indicated by the reference signal is equal to or higher than the volume of the sound indicated by the second sound signal, the second generation means may adjust the volume of the sound indicated by the second sound signal. The output sound signal may be generated by changing the volume of the first sound signal based on a coefficient for increasing to a level that matches the volume of the sound indicated by the reference signal. As a result, the sound control device can adjust the sound volume output from the speaker so that the sound volume at the position of the sound control device matches a predetermined level. Furthermore, it can suppress efficiently.

  In the present invention, when the volume of the sound indicated by the reference signal is less than the volume of the sound indicated by the second sound signal, the output means may not output the sound via the speaker. As a result, the sound control apparatus can minimize current consumption associated with outputting sound from the speaker.

  In the present invention, a second acquisition unit that acquires a set value of a volume of a sound output from the speaker is provided, and the first generation unit is specified according to the set value acquired by the second acquisition unit. The reference signal corresponding to the first sound signal may be generated based on the coefficient. Thus, the sound control device can generate a reference signal in accordance with the set value of the volume and use it for comparison with the second sound signal. Thus, the sound control device can adjust the sound volume output from the speaker so that the sound volume at the position of the sound control device becomes a level specified by the set value, and can output from the speaker.

  In the present invention, a third acquisition unit that acquires a voltage of a battery that drives the sound control device is provided, and the first generation unit is configured to perform the first sound based on the voltage acquired by the third acquisition unit. The reference signal corresponding to the signal may be generated. As a result, the sound control device can further suppress the volume of the sound output from the speaker when the battery voltage is low. Thus, the sound control device can extend the drive time of the sound control device by the battery by suppressing the power consumption of the speaker according to the voltage of the battery.

1 is a diagram showing an outline of a sound control system 1. FIG. It is a figure which shows a mode that the sound output from the sound control apparatus 21 is transmitted to the sound control apparatus 22. FIG. 3 is a block diagram showing an electrical configuration of the sound control device 20. FIG. FIG. 4 is a block diagram illustrating a signal flow of the sound control device 22. It is a figure which shows the 1st graph 541, the 2nd graph 542, and the 3rd graph 543. FIG. It is a flowchart of an output process. It is a flowchart of a coefficient determination process. It is a flowchart of a coefficient change process. It is a block diagram which shows the flow of the signal of the sound control apparatus 22 in a modification. It is a figure which shows the 2nd graph 544 in a modification.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The outline of the sound control system 1 will be described with reference to FIG. The sound control system 1 includes personal computers (PCs) 11 and 12 (hereinafter also collectively referred to as “PC13”) and sound control devices 21 to 24 (hereinafter collectively referred to as “sound control device 20”). .). The PC 11 and the sound control devices 21 and 22 are installed in the same place (hereinafter referred to as “first place 3”). The PC 12 and the sound control devices 23 and 24 are installed in a second place 4 different from the first place 3. Users 31 to 34 are arranged in the vicinity of the sound control devices 21 to 24, respectively. Hereinafter, the users 31 to 34 are collectively referred to as a “user 30”.

  The sound control device 21 is connected to the PC 11 via a universal serial bus (USB (registered trademark)). The sound control device 22 is connected to the sound control device 21 via the USB. The sound control device 23 is connected to the PC 12 via the USB. The sound control device 24 is connected to the sound control device 23 via the USB. The sound control device 20 is driven by power supplied via USB. The sound control device 20 includes a battery 60 and can also be driven by the battery 60. The sound control device 20 is driven by the battery 60 when power is not supplied via the USB. For example, the sound control devices 21 and 23 are driven by the battery 60 when connected to the PC 13 that cannot supply power via the USB. For example, the sound control devices 22 and 24 are driven by the battery 60 when connected to the sound control devices 21 and 23 driven by the battery 60.

  The PCs 11 and 12 are connected to the Internet network 2, respectively. The PCs 11 and 12 can communicate with each other via the Internet network 2. Note that the connection method between the sound control devices 21 and 23 and the PCs 11 and 12 and the connection method between the sound control devices 21 and 23 and the sound control devices 22 and 24 may be other than USB. Good. For example, it may be connected by wireless of any communication method (Bluetooth (registered trademark), wireless LAN, etc.).

  Each of the sound control devices 21 to 24 collects sound via the microphone 57 (see FIG. 3). The sound control device 22 transmits a collected sound signal (hereinafter referred to as “sound signal”) to the sound control device 21. The sound signal indicates a plurality of discrete values obtained by quantizing the sound waveform. The sound control device 21 receives a sound signal from the sound control device 22. The sound control device 21 superimposes the sound signal received through the microphone 57 of the sound control device 21 on the sound signal received from the sound control device 22. The sound control device 21 transmits the superimposed sound signal to the sound control device 23 via the PC 11, the Internet network 2, and the PC 12. The sound control device 23 transmits the received sound signal to the sound control device 24. The sound control devices 23 and 24 each output a sound having a waveform reproduced based on the sound signal from the speaker 58 (see FIG. 3). As a result, the users 33 and 34 can hear the sounds of the users 31 and 32 and the sound in the first place 3. Hereinafter, the sound of the waveform reproduced based on the sound signal is simply referred to as “sound indicated by the sound signal”.

  The sound control device 24 transmits the sound signal of the sound collected via the microphone 57 to the sound control device 23 via the USB. The sound control device 23 receives the sound signal from the sound control device 24 and superimposes the sound signal of the sound collected via the microphone 57 on the received sound signal. The sound control device 23 transmits the superimposed sound signal to the sound control device 21 via the PC 12, the Internet network 2, and the PC 11. The sound control device 21 transmits the received sound signal to the sound control device 22. The sound control devices 21 and 22 each output the sound indicated by the sound signal from the speaker 58. As a result, the users 31 and 32 can hear the sounds of the users 33 and 34 and the sound in the second location 4.

  As described above, the sound control system 1 transmits and receives sound signals between the sound control devices 20 installed in the first place 3 and the second place 4, respectively, so that the first place 3 and the second place 4. It is a system that can hold an audio conference between. In the sound control system 1, a plurality of sound control devices 20 can be scattered over a wide area. As a result, the sound output from the speaker 58 of the sound control device 20 can be heard in a wide range. Further, the sound can be collected in a wide area by the microphone 57 of the sound control device 20.

  The sound control devices 21 and 22 at the first place 3 each output the same sound indicated by the same sound signal transmitted from the sound control device 23 at the second place 4 from the speaker 58. Therefore, for example, when the sound control devices 21 and 22 are installed close to each other, the sound volume at the position of the sound control device 22 is output from the speaker 58 of the sound control device 21 and transmitted to the sound control device 22. This is the volume of the sound in which the sound and the sound output from the speaker 58 of the sound control device 22 are superimposed.

  For example, when the volume of the sound output from the speaker 58 of the sound control device 21 and transmitted to the sound control device 22 is large, the sound control device 22 is connected from the speaker 58 in order to set the sound volume at the position of the sound control device 22 to a predetermined level. The volume of the output sound may be small. Therefore, when the sound control device 22 receives a sound output from the speaker 58 of the sound control device 21 through the microphone 57 at a high sound volume, the sound control device 22 can reduce the sound volume output from the speaker 58. In addition, when the volume of the sound output from the speaker 58 of the sound control device 21 and transmitted to the sound control device 22 exceeds a predetermined level, the sound control device 22 does not output sound from the speaker 58. The volume of the sound at the position is above a predetermined level. Therefore, in the above case, if the sound control device 22 can reduce the volume of the sound output from the speaker 58 or can prevent the sound from being output, the sound control device 22 associated with the sound output from the speaker 58 can be used. It is preferable because power consumption can be suppressed.

  Therefore, the CPU 51 of the sound control device 22 receives the sound output from the speaker 58 of the sound control device 21 via the microphone 57 and outputs the same sound from the speaker 58 based on the volume of the received sound. Adjust the volume.

  Specifically, it is as shown in FIG. The sound control device 22 collects the sound output from the speaker 58 of the sound control device 21 via the microphone 57. The sound control device 22 receives a sound signal of the same sound as the sound collected via the microphone 57 from the sound control device 21 via the USB.

  As shown in FIG. 2A, when the volume of the collected sound is low, the sound control device 22 uses a sound signal received via the USB to set the sound volume at the position of the sound control device 22 to a predetermined level. The indicated sound is output from the speaker 58 at a high volume. As shown in FIG. 2B, when the volume of the collected sound is high, the sound control device 22 uses the sound signal received via the USB to set the sound volume at the position of the sound control device 22 to a predetermined level. Is output from the speaker 58 at a low volume. In addition, as shown in FIG. 2C, when the volume of the collected sound is larger and the volume of the sound at the position of the sound control device 22 is equal to or higher than a predetermined level, the sound control device 22 receives it via USB. The sound indicated by the sound signal is not output from the speaker 58.

  By performing the control as described above, the sound control device 22 can adjust the volume of the sound output from the speaker 58 as necessary. Therefore, the power consumption of the sound control device 22 accompanying the sound output from the speaker 58 Can be suppressed. Further, by performing the control as described above, it is possible to transmit a sound having a sufficient volume to the user 32 in the vicinity of the sound control device 22.

  In the present embodiment, it is assumed that only the sound control devices 22 and 24 are the sound control devices 20 that perform the volume control described above. The sound control device 21 directly connected to the PC 11 and the sound control device 23 directly connected to the PC 12 do not perform the above volume control.

  The configuration of the sound control system 1 can be changed to a configuration other than that shown in FIG. For example, the sound control devices 21 and 22 may be directly connected to the Internet network 2. The sound control devices 21 and 22 may directly communicate with each other via the Internet network 2. Still another sound control device may be connected to the sound control devices 22 and 24 via USB. Each of the sound control devices 21 and 22 may be directly connected to the PC 11, and each of the sound control devices 23 and 24 may be directly connected to the PC 12. The PC 11 and the sound control device 21, the sound control devices 21 and 22, the PC 12 and the sound control device 23, and the sound control devices 23 and 24 may be connected by a LAN cable or wirelessly. (For example, wireless LAN or Bluetooth (registered trademark)) may be used for connection. The volume control described above may be executed by all of the sound control devices 21 to 24.

  The electrical configuration of the sound control device 20 will be described with reference to FIG. The sound control device 20 includes a CPU 51. The CPU 51 is electrically connected to the ROM 52, RAM 53, flash memory 54, USB I / F 55, operation unit 56, A / D converter 68, D / A converter 65, and battery drive circuit 59. The A / D converter 68 is electrically connected to the microphone 57 via an analog amplifier circuit (mic amplifier, etc.) not shown, and the D / A converter 65 is connected via an analog amplifier circuit (speaker amplifier, etc.) not shown. Are electrically connected to the speaker 58. The battery drive circuit 59 is connected to the battery 60.

  The ROM 52 stores a boot program, BIOS, OS, and the like. The RAM 53 stores timers, counters, and temporary data. The flash memory 54 stores a program for the CPU 51. The flash memory 54 stores information indicating a first graph 541 (see FIG. 5), a second graph 542 (see FIG. 5), and a third graph 543 (see FIG. 5). The USB I / F 55 is an interface element for performing communication via USB. The operation unit 56 is a push button capable of performing an input operation. The operation unit 56 includes a volume button for setting the volume of the sound output from the speaker 58 in the sound control device 20. The battery drive circuit 59 is a circuit that monitors the voltage of the battery 60.

  A signal flow in the sound control device 22 will be described with reference to FIG. The CPU 51 receives the sound signal Kc from the sound control device 21 via the USB I / F 55. The CPU 51 decodes and combines the received sound signal Kc and generates the first sound signal K1 (data receiving unit 61). When the CPU 51 accepts an operation for setting the volume of the speaker via the volume button of the operation unit 56, the CPU 51 acquires a set volume value (hereinafter referred to as “set value Vc”) (state determination unit). 70). The CPU 51 acquires the voltage Vb of the battery 60 via the battery drive circuit 59 (state determination unit 70).

  The CPU 51 generates a reference signal Kr obtained by converting the first sound signal K1 (reference signal generation unit 62). The reference signal Kr is a first sound signal based on the relationship between the output sound and the collected sound when the sound output from the speaker 58 by the sound control device 22 is directly collected via the microphone 57. This is a signal obtained by converting K1. That is, the reference signal Kr indicates a sound signal of a sound that is assumed to be collected through the microphone 57 when the sound indicated by the first sound signal K1 is output from the speaker 58. The CPU 51 refers to information indicating the first graph 541 (see FIG. 5) and the second graph 542 (see FIG. 5) stored in the flash memory 54. The CPU 51 generates the reference signal Kr based on the relationship between the setting value Vc, the volume V (Ki), and the reference coefficient P specified by the information to be referenced.

  In the present embodiment, the first graph 541 and the second graph 542 have been described for ease of explanation, but the present invention may generate the reference signal Kr based on other information. For example, the reference signal Kr may be generated by applying the relational expressions shown in the first graph 541 and the second graph 542, or the reference signal Kr is generated by applying a discrete value lookup table. Also good.

  As shown in FIG. 5A, the first graph 541 shows a relationship between an arbitrary set value Vc and a sound volume V (Ki) (described later). The first graph 541 is determined as follows. An arbitrary sound is output from the speaker 58 in a state where the volume is set to a specific set value Vc. At the same time, the microphone 57 collects the sound output from the speaker 58. The relationship between the volume V (Ki) of the collected sound and the specific set value Vc is specified. The above processing is repeatedly executed while changing the volume of the sound output from the speaker 58. A first graph 541 including a curve 541A indicating the identified relationship is stored in the flash memory 54. Therefore, the curve 541A shows the relationship between the volume of the output sound and the collected sound when the sound output from the speaker 58 by the sound control device 22 is directly collected via the microphone 57. . In addition, the first graph 541 includes a curve 541B having a large inclination with respect to the curve 541A and a curve 541C having a small inclination. As shown in FIG. 5B, the second graph 542 shows the relationship between the volume V (Ki) and the reference coefficient P. The second graph 542 includes curves 542A, 542B, 542C. The curves 542A, 542B, and 542C correspond to the curves 541A, 541B, and 541C of the first graph 541, respectively.

  The first graph 541 and the second graph 542 are determined by executing the above determination method before using the sound control device 22, and information indicating each is stored in the flash memory 54. Thereafter, when the CPU 51 receives the sound signal Kc from the sound control device 21 via the USB I / F 55, the CPU 51 applies the first graph 541 and the second graph 542 stored in the flash memory 54 as described later. The reference coefficient P is specified by

  When the CPU 51 generates the first sound signal K1 based on the sound signal Kc received via the USB I / F 55, the CPU 51 first acquires the volume setting value Vc of the speaker 58. The CPU 51 specifies the volume V (Ki) corresponding to the set value Vc by applying the acquired set value Vc to any of the curves 541A, 541B, and 541C of the first graph 541. Next, the CPU 51 applies one of the curves 542A, 542B, and 542C of the second graph 542, and specifies the reference coefficient P corresponding to the specified volume V (Ki).

  Note that the Y axis of the first graph 541 and the X axis of the second graph 542 both indicate the volume V (Ki). Therefore, if information indicating a graph indicating the correspondence between the set value Vc and the reference coefficient P is stored in the flash memory 54 and applied, the reference coefficient P can be directly specified based on the set value Vc. is there. However, in the present embodiment, two graphs (first graph 541 and second graph 542) are used to specify the reference coefficient P based on the set value Vc. The reason is that the method for obtaining each graph is different. That is, in the first graph 541, the relationship between the set value Vc and the volume V (Ki) is obtained by using a sound signal (white noise or the like) having a frequency wider than the voice band. On the other hand, in the second graph 542, the relationship between the volume V (Ki) and the reference coefficient P is obtained by using a sound signal having a frequency equal to the voice band. Thus, two graphs are used to facilitate the correction process for both separately.

  Note that which of the curves 541A, 541B, 541C of the first graph 541 and the curves 542A, 542B, 542C of the second graph 542 is applied is based on the battery voltage Vb acquired by the state determination unit 70. Determined. Specifically, it is as follows. If the battery voltage Vb is greater than the predetermined first threshold, it is determined that the remaining battery capacity is large. In this case, there is no problem even if sound is output from the speaker 58 at a high volume. Therefore, the CPU 51 applies the curve 541B of the first graph 541 and the curve 542B of the second graph 542 so that the specified reference coefficient P becomes larger. Further, when the battery voltage Vb is less than a predetermined second threshold value that is smaller than the first threshold value, it is determined that the remaining battery capacity is low. In this case, it is necessary to reduce power consumption by reducing the volume of the sound output from the speaker 58. Therefore, the CPU 51 applies the curve 541C of the first graph 541 and the curve 542C of the second graph 542 so that the specified reference coefficient P becomes smaller. When the battery voltage Vb is not less than the second threshold and not more than the first threshold, the CPU 51 applies the curve 541A of the first graph 541 and the curve 542A of the second graph 542.

  In the above description, when the sound control device 20 is driven by the power supplied via USB, the state determination unit 70 may acquire the voltage of the power supplied via USB as the voltage Vb. In this case, since the acquired voltage Vb is always greater than or equal to the second threshold and less than or equal to the first threshold, the curve 541A of the first graph 541 and the curve 542A of the second graph 542 are applied.

Finally, the CPU 51 generates the reference signal Kr by multiplying the first sound signal K1 by the identified reference coefficient P (see Equation 1).
Kr = P × K1 (Formula 1)
As shown in FIG. 2D, the calculated reference signal Kr is a sound to be collected that is assumed when the sound indicated by the first sound signal K1 is output from the speaker 58 at the volume of the set value Vc. It corresponds to a sound signal.

  When the remote conference is started, the CPU 51 collects sound via the microphone 57. Note that the collected sound includes, for example, a voice uttered by the user 32. Further, when sound is output from the speaker 58 of the sound control device 21, this sound is also included in the collected sound. In addition, when the sound control device 21 is transmitting a sound signal, the CPU 51 receives the sound signal Kc via the USB I / F 55 and generates the first sound signal K1. The sound indicated by the first sound signal K1 is the same as the sound output from the speaker 58 of the sound control device 21.

  The collected sound is amplified by an analog amplification circuit (not shown) and then digitized by an A / D converter 68 to generate a sound signal. The CPU 51 removes the same sound as the sound indicated by the first sound signal K1 (that is, the sound output from the speaker 58 of the sound control device 21) among the generated sound signals (for example, the sound of the user 32). Kj is extracted using a known echo cancellation technique (input control unit 69). The CPU 51 encodes and packetizes the extracted sound signal and generates a sound signal Kc (data receiving unit 67). The CPU 51 transmits the generated sound signal Kc to the sound control device 21 via the USB I / F 55.

  In addition, the CPU 51 extracts a sound signal having the same sound as the sound indicated by the first sound signal K1 from the generated sound signals by the input control unit 69 as the second sound signal K2, using a known echo cancellation technique. . The CPU 51 compares the sound volume V (Kr) indicated by the reference signal Kr with the sound volume V (K2) indicated by the second sound signal K2 (signal comparison unit 63). As shown in FIGS. 2A and 2B, when the volume V (K2) is smaller than the volume V (Kr), that is, when the volume V (Kr) is equal to or higher than the volume V (K2), the sound control device 22 The volume of the sound indicated by the first sound signal K1 is adjusted and output from the speaker 58.

The volume is adjusted based on the adjustment coefficient Q specified by referring to the information indicating the third graph 543 (see FIG. 5) stored in the flash memory 54 as follows. As shown in FIG. 5C, the third graph 543 includes a plurality of curves 543A indicating the relationship between the difference V (Kr) −V (K2) between the volume V (Kr) and the volume V (K2) and the adjustment coefficient q. 543B and 543C are included. The adjustment coefficient q is set to the volume V (K2) in order to increase the volume V (K2) of the sound indicated by the second sound signal K2 to a level that matches the volume V (Kr) of the sound indicated by the reference signal Kr. Indicates the multiplier to multiply. The relationship of the following formula | equation 2 is materialized between the volume V (Kr) and the volume V (K2).
V (Kr) = q × V (K2) (Formula 2)

  The third graph 543 shows the difference V (Kr) −V (K2) and a multiplier (adjustment coefficient q) for multiplying the volume V (K2) to increase the volume V (K2) to the volume V (Kr). Showing the relationship. As the difference V (Kr) −V (K2) is larger, the multiplier for increasing the volume V (K2) to the volume V (Kr) is larger, and the adjustment coefficient q is larger. The CPU 51 determines the adjustment coefficient q corresponding to the difference V (Kr) −V (K2) by applying one of the curves 543A to 543C of the third graph 543.

The adjustment coefficient Q is an average of a plurality of adjustment coefficients q. The CPU 51 calculates the adjustment coefficient Q based on the plurality of adjustment coefficients q. The CPU 51 multiplies the calculated adjustment coefficient Q by the first sound signal K1 to generate an output sound signal Ko that is a sound signal output from the speaker 58 (see the output control unit 64 and Equation 3).
Ko = Q × K1 (Formula 3)

  Note that which of the curves 543A to 543C of the third graph 543 is to be applied is determined based on the set value Vc acquired by the state determination unit 70. Specifically, it is as follows. For example, when the acquired setting value Vc is larger than the current sound volume setting value, an input operation for increasing the sound volume is performed. Therefore, the CPU 51 applies the curve 543B in which a larger adjustment coefficient q is specified for an arbitrary difference V (Kr) −V (K2). When the acquired set value Vc is smaller than the current volume setting value, an input operation for decreasing the volume is performed. Therefore, the CPU 51 applies the curve 543C in which a smaller adjustment coefficient q is specified for an arbitrary difference V (Kr) −V (K2). When the acquired setting value Vc is the same as the current sound volume setting value, the CPU 51 applies the curve 543B.

  Note that which of the curves 543A to 543C of the third graph 543 is applied may be determined based on the battery voltage Vb acquired by the state determination unit 70. Specifically, it is as follows. When the battery voltage Vb is larger than the first threshold, the CPU 51 applies the curve 543B. When the battery voltage Vb is less than the second threshold, the CPU 51 applies the curve 543C. Further, when the battery voltage Vb is greater than or equal to the second threshold value and less than or equal to the first threshold value, the CPU 51 applies the curve 543B.

  The CPU 51 outputs the output sound signal Ko to the D / A converter 65. The D / A converter 65 converts the output sound signal Ko to analog. The analog output sound signal Ko is amplified by an analog amplifier circuit (not shown). The speaker 58 outputs a sound indicated by the amplified output sound signal Ko.

  On the other hand, as shown in FIG. 2C, when the volume V (K2) is equal to or higher than the volume V (Kr), that is, when the volume V (Kr) is less than the volume V (Kr), the CPU 51 sets 0 as the adjustment coefficient. Is identified. Since the output sound signal Ko generated based on the specified adjustment coefficient Q is 0, the sound indicated by the first sound signal K1 is not output from the speaker 58 of the sound control device 22.

  The information indicating the third graph 543 is determined at the same time when the first grab 541 and the second graph 542 are determined before using the sound control device 22, and is flashed together with the first graph 541 and the second graph 542. Stored in the memory 54.

  Processing executed by the CPU 51 of the sound control device 22 will be described with reference to FIGS. When the power of the sound control device 22 is turned on, the CPU 51 reads out and executes a program stored in the flash memory 54, thereby performing output processing (see FIG. 6) and coefficient determination processing (see FIG. 7). Run. The output process and the coefficient determination process are executed in parallel.

  The output process will be described with reference to FIG. When the output process is started, the microphone 57 starts collecting sound. The A / D converter 68 starts the process of digitizing the collected sound and generating a sound signal. CPU51 starts the process which acquires the sound signal of the same sound as the sound shown by the 1st sound signal produced | generated by S17 mentioned later among the produced | generated sound signals as the 2nd sound signal K2 (S11). The CPU 51 stores the acquired second sound signal K2 in the RAM 53. The CPU 51 starts the process of reading the output sound signal Ko stored in the RAM 53 in S19 described later and outputting it to the D / A converter 65 (S13). As a result, the D / A converter 65 converts the output sound signal Ko to analog, and the speaker 58 outputs the sound indicated by the output sound signal Ko.

  The CPU 51 receives the sound signal Kc transmitted from the sound control device 21 via the USB I / F 55 (S15). The CPU 51 decodes and combines the received sound signal Kc and generates the first sound signal K1 (S17). The CPU 51 stores the generated first sound signal K1 in the RAM 53 in association with the second sound signal K2 that is the same sound as the sound indicated by the first sound signal K1 and acquired in S11.

  The CPU 51 multiplies the first sound signal K1 generated in S17 and stored in the RAM 53 by the adjustment coefficient Q determined by a coefficient determination process (see FIG. 7) described later to generate an output sound signal Ko (S19). . The CPU 51 stores the generated output sound signal Ko in the RAM 53. Note that the output sound signal Ko stored in the RAM 53 is read out based on the processing started in S 13 and output to the D / A converter 65. The sound indicated by the output sound signal Ko is output from the speaker 58. The CPU 51 returns the process to S15.

  The coefficient determination process will be described with reference to FIG. The CPU 51 acquires the first sound signal K1 generated in S17 and stored in the RAM 53 (S21). CPU51 performs a coefficient change process (refer FIG. 8) (S22). In the coefficient changing process, it is selected which of the curves 541A to 541C included in the first graph 541 and the curves 542A to 542C included in the second graph 542 is applied.

  The coefficient changing process will be described with reference to FIG. CPU51 acquires battery voltage Vb (S51). The CPU 51 selects one of the curves 541A to 541C included in the first graph 541 and the curves 542A to 542C included in the second graph 542 based on the acquired battery voltage Vb (S53). Note that any one of the selected curves 541A to 541C and any one of the curves 542A to 542C are applied when the reference coefficient P is determined in S25 (see FIG. 7).

  The CPU 51 acquires the volume setting value Vc (S55). The CPU 51 selects one of the curves 543A to 543C included in the third graph 543 based on the acquired setting value Vc (S57). One of the selected curves 543A to 543C is applied when the adjustment coefficient q is determined in S33 (see FIG. 7). The CPU 51 ends the coefficient changing process and returns the process to the coefficient determining process (see FIG. 7).

  As shown in FIG. 7, after the coefficient determination process (S22) is completed, the CPU 51 specifies the volume V (K1) of the sound indicated by the first sound signal K1 acquired in S21 (S23). The CPU 51 selects one of the curves 541A to 541C selected in the coefficient changing process (S22) in the first graph 541 and the coefficient changing process (S22) in the second graph 542 (see FIG. 5). The reference coefficient P is determined based on any of the curves 542A to 542C (S25). The CPU 51 multiplies the determined reference coefficient P by the first sound signal K1 to generate a reference signal Kr (S27).

  The CPU 51 acquires from the RAM 53 a second sound signal K2 that indicates the same sound as the sound indicated by the first sound signal K1 that is the source of the generated reference signal Kr. The CPU 51 calculates the difference between the sound volume V (Kr) indicated by the reference signal Kr generated in S27 and the sound volume V (K2) indicated by the acquired second sound signal K2 (S29). When the CPU 51 determines that the difference is 0 or more (S31: YES), the CPU 51 determines the adjustment coefficient q based on the third graph 543 (see FIG. 5) (S33). Note that which of the curves 543A to 543C included in the third graph 543 is to be applied is determined by executing a coefficient changing process (see FIG. 8) in S22. The CPU 51 stores the determined adjustment coefficient q in the RAM 53 in association with the determined time (S37).

  When S37 is repeated, a plurality of adjustment coefficients q are stored in the RAM 53. The CPU 51 acquires a plurality of adjustment coefficients q determined within a predetermined time from the current time among the plurality of adjustment coefficients q stored in the RAM 53 based on the associated time (S39). CPU51 calculates the average of the acquired adjustment coefficient q, and determines as the adjustment coefficient Q (S41). The CPU 51 returns the process to S29. Note that the CPU 51 generates the output sound signal Ko by multiplying the first sound signal K1 by the adjustment coefficient Q determined in S19 (see FIG. 6). The CPU 51 outputs the output sound signal Ko to the D / A converter 65 in S13 (see FIG. 6), whereby the sound indicated by the output sound signal Ko is output from the speaker 58.

  On the other hand, when the CPU 51 determines that the difference calculated in S29 is less than 0 (S31: NO), the CPU 51 determines the adjustment coefficient Q to 0 (S35). The CPU 51 returns the process to S29. Note that the CPU 51 generates the output sound signal Ko by multiplying the first sound signal K1 by the adjustment coefficient Q determined in S19 (see FIG. 6). When the adjustment coefficient Q is set to 0, the output sound signal Ko generated in S19 (see FIG. 6) is also set to 0. For this reason, even if the output sound signal Ko is output to the D / A converter 65 in S13 (see FIG. 6), no sound is output from the speaker 58.

  As described above, the sound control device 22 receives the sound output from the speaker 58 of the sound control device 21 via the microphone 57 and acquires the second sound signal K2 (S11). The sound control device 22 receives the sound signal Kc from the sound control device 21 via the USB, and acquires the first sound signal K1 (S17). The sound control device can change the volume V (K1) of the sound indicated by the first sound signal K1 based on the volume V (K2) of the second sound signal K2 and output it from the speaker 58 (S13). .

  The sound control device 22 determines an adjustment coefficient Q according to the difference between the volume V (Kr) and the volume V (K2) of the sound indicated by the reference signal Kr (S41), and multiplies the first sound signal K1. Thus, the output sound signal Ko of the sound output from the speaker 58 is generated (S19). When the volume V (K2) of the second sound signal K2 received and acquired through the microphone 57 is small, the sound control device 22 generates the output sound signal Ko by applying a large adjustment coefficient Q to the first sound signal K1. By doing so, the volume of the sound output from the speaker 58 can be increased. Thus, the sound control device 22 can transmit to the user 31 a sound having a volume that can be recognized by the user 31. On the other hand, when the volume V (K2) of the second sound signal K2 received and acquired through the microphone 57 is large, the output sound signal Ko is generated by applying a small adjustment coefficient Q to the first sound signal K1. The volume of the sound output from the speaker 58 can be reduced. As a result, the sound control device 22 can maintain the sound volume at the position of the sound control device 22 at a predetermined level, and can suppress power consumption associated with outputting sound from the speaker 58.

  The sound control device 22 generates the reference signal Kr by multiplying the first sound signal K1 by the reference coefficient P (S27), and the sound volume V (Kr) indicated by the generated reference signal Kr is the first sound signal K1. The adjustment coefficient Q is determined when the sound volume is equal to or higher than the sound volume V (K2) indicated by the two-tone signal K2. The reference signal Kr indicates a sound signal of a sound that is assumed to be collected via the microphone 57 when the sound indicated by the first sound signal K1 is output from the speaker 58 (see FIG. 12D). Therefore, the sound control device 22 can determine the adjustment coefficient Q by setting the reference signal Kr as an appropriate standard for determining the adjustment coefficient Q, so that the volume of the sound output from the speaker 58 is adjusted to an appropriate level. it can. Therefore, the sound control device 22 can efficiently suppress current consumption associated with outputting sound from the speaker 58.

  The sound control device 22 generates the reference signal Kr according to the volume setting value Vc and can be used for comparison with the volume V (K2) of the second sound signal K2. A reference signal Kr can be generated. Therefore, the sound control device 22 can generate an output signal Ko having an appropriate volume according to the set value Vc of the volume.

  When the volume V (Kr) is less than the volume V (K2) (S31: NO), the sound control device 22 sets the adjustment coefficient Q to 0 (S35) and does not output a sound from the speaker 58. As a result, the sound control device 22 can minimize current consumption associated with outputting sound from the speaker.

  Further, the sound control device 22 acquires the battery voltage Vb (S51), and determines the reference coefficient P among the curves 541A to 541C of the first graph 541 and the curves 542A to 542C of the second graph 542 according to the voltage Vb. A curve to be applied for determination is selected (S53). For this reason, the sound control device 22 can further reduce the volume of the sound output from the speaker 58 when the battery voltage is low. Therefore, the sound control device 22 can extend the drive time of the sound control device 22 by the battery by further suppressing the power consumption associated with outputting the sound from the speaker 58.

  Further, the sound control device 22 acquires the volume setting value Vc of the speaker 58 (S55), and is applied to determine the adjustment coefficient q among the curves 543A to 543C of the third graph 543 according to the setting value Vc. A curve to be selected is selected (S57). For this reason, the sound control device 22 can reflect the change in the set value Vc on the volume of the sound output from the speaker 58. For example, the case where the echo of the sound in the 1st place 3 is small is mentioned as an example. In such a case, the user 30 may input an instruction to increase the volume via the operation unit 56 of the sound control device 22 because the sound transmitted from the speaker 58 of the sound control device 22 is weakly transmitted. is there. In this case, the sound control device 22 can select the curve 543B where a larger adjustment coefficient q is determined. As a result, a louder sound is output from the speaker 58 of the sound control device 22, so that the user 30 can hear the sound output from the speaker 58 of the sound control device 22 satisfactorily.

  In addition, this invention is not limited to the said embodiment, A various change is possible. In the above embodiment, the reference signal is not limited to a signal indicating the sound itself. For example, the reference signal may be data indicating the volume.

  For example, a case where the distance between the sound control devices 21 and 22 is large is taken as an example. In this case, the sound volume V (K2) when the sound controller 22 receives the sound output from the speaker 58 of the sound controller 21 via the microphone 57 may be very small. In this case, in S31, it is determined that the difference V (Kr) −V (K2) (≈0) approximates the sound volume V (Kr). In such a case, the CPU 51 may further increase the adjustment coefficient q determined based on the third graph 543 so that the adjustment coefficient Q calculated in S41 becomes larger. For example, the CPU 51 may increase the adjustment coefficient q by multiplying the adjustment coefficient q determined based on the third graph 543 by one or more coefficients. In this case, since the volume V (Ko) of the sound indicated by the output sound signal Ko is further increased, a louder sound is output from the speaker 58 of the sound control device 22. Therefore, even when the distance between the sound control devices 21 and 22 is large, the sound control device 22 can transmit the sound output from the speaker 58 to the user 31 arranged in the vicinity of the sound control device 21.

  CPU51 determines the curve applied in order to determine the adjustment coefficient q among the curves 543A-543C of the 3rd graph 543 according to the acoustic environment of the 1st place 3 in which the sound control apparatus 22 is installed. Also good. For example, the CPU 51 acquires the reverberation characteristic of the first place 3, and selects a curve to be applied to determine the adjustment coefficient q from the curves 543A to 543C of the third graph 543 according to the acquired reverberation characteristic. Good. For example, the CPU 51 selects the curve 543C so that the determined adjustment coefficient q is small when it is determined that the environment is high in reverberation, and the adjustment coefficient q is determined when it is determined that the environment is low in reverberation. The curve 543B may be selected so that becomes larger.

  In the above embodiment, the adjustment coefficient q of the third graph 543 is set so that the sound volume V (K2) indicated by the second sound signal K2 matches the sound volume V (Kr) indicated by the reference signal Kr. In order to increase it, it was set as the multiplier which multiplies volume V (K2). The adjustment coefficient q may be a multiplier that multiplies the volume V (K2) to increase the volume V (K2) to a level that approximates the volume V (Kr). Further, the level approximate to the sound volume V (Kr) may be set by the user 30.

  In the above embodiment, when the CPU 51 determines that the difference calculated in S29 is less than 0 (S31: NO), the CPU 51 determines the adjustment coefficient Q to 0 (S35). On the other hand, when the CPU 51 determines that the difference calculated in S29 is less than 0 (S31: NO), the CPU 51 prohibits the output sound signal Ko from being output to the D / A converter 65 in S13. May be prohibited.

  FIG. 9 shows a signal flow of the sound control device 22 in the modification. The difference from FIG. 4 is that an input determination unit 71 is added. When the sound volume V (K1) indicated by the first sound signal K1 is equal to or lower than a predetermined threshold, the CPU 51 includes a large percentage of the sound uttered by the user 32 in the sound collected through the microphone 57. Therefore, it is determined that the ratio of the sound output from the speaker 58 of the sound control device 21 is small. In this case, the volume V (K2) of the sound indicated by the second sound signal K2 is also reduced. In such a case, the CPU 51 determines the reference coefficient P by applying the fourth graph 544 (see FIG. 10) based on the sound signal Kj of the sound collected through the microphone 57 (input determination unit 71). Then, the reference signal Kr is generated (reference signal generator 62).

  As shown in FIG. 10, the curve 544A included in the fourth graph 544 adjusts the slope so that a smaller reference coefficient P is specified as the volume V (Kj) of the sound indicated by the sound signal Kj increases. Has been. When the reference coefficient P is specified based on the fourth graph 544, the specified reference coefficient P decreases as the volume of the voice uttered by the user 32 increases, and the sound indicated by the generated reference signal Kr is reduced. The volume is also reduced. Therefore, when the sound volume V (Kr) indicated by the reference signal Kr and the sound volume V (K2) indicated by the second sound signal K2 are compared (signal comparison unit 63), the sound signal K2 Even when the sound volume V (K2) shown is small, the adjustment coefficient Q can be determined accurately.

  The USB I / F 55 corresponds to the “communication unit” of the present invention. The CPU 51 that performs the process of S15 corresponds to the “reception unit” of the present invention. The CPU 51 that performs the process of S27 corresponds to the “first generation unit” of the present invention. The CPU 51 that performs the process of S11 corresponds to the “first acquisition unit” of the present invention. The CPU 51 that performs the process of S19 corresponds to the “second generation unit” of the present invention. The CPU 51 that performs the process of S13 corresponds to the “output unit” of the present invention. The CPU 51 that performs the process of S55 corresponds to the “second acquisition unit” of the present invention. The CPU 51 that performs the process of S51 corresponds to the “third acquisition unit” of the present invention.

1 sound control system 20, 21, 22, 23, 24 sound control device 51 CPU
54 Flash memory 541 1st graph 542 2nd graph 543 3rd graph 57 Microphone 58 Speaker

Claims (6)

A sound control device including a communication unit that communicates with a microphone, a speaker, and another sound control device,
Receiving means for receiving a sound signal, which is a signal indicating sound, from the other sound control device via the communication unit;
First generating means for generating a reference signal corresponding to the first sound signal based on a coefficient specified in accordance with the first sound signal corresponding to the sound signal received by the receiving means;
First acquisition means for acquiring a second sound signal that is a signal of the same sound when the same sound as the sound indicated by the first sound signal is collected via the microphone;
The first sound level according to a comparison result between the sound volume indicated by the second sound signal acquired by the first acquisition means and the sound volume indicated by the reference signal generated by the first generation means. Second generating means for converting the sound signal and generating an output sound signal;
Output means for outputting a sound indicated by the output sound signal via the speaker based on the output sound signal generated by the second generation means;
A sound control apparatus comprising: The second generation means includes
When the volume of the sound indicated by the reference signal is equal to or higher than the volume of the sound indicated by the second sound signal, the volume of the sound indicated by the second sound signal is changed to the volume of the sound indicated by the reference signal. The sound control apparatus according to claim 1, wherein the output sound signal is generated by changing a volume of the first sound signal based on a coefficient that is increased to an approximate level. The second generation means includes
When the volume of the sound indicated by the reference signal is equal to or higher than the volume of the sound indicated by the second sound signal, the volume of the sound indicated by the second sound signal is set as the volume of the sound indicated by the reference signal. The sound control apparatus according to claim 2, wherein the output sound signal is generated by changing a volume of the first sound signal based on a coefficient that is increased to a matching level. The output means includes
The sound is not output through the speaker when the volume of the sound indicated by the reference signal is less than the volume of the sound indicated by the second sound signal. The sound control device described. A second acquisition means for acquiring a set value of the volume of the sound output from the speaker;
The first generation means includes
5. The reference signal corresponding to the first sound signal is generated based on the coefficient specified according to the set value acquired by the second acquisition means. The sound control device according to the above. A third acquisition means for acquiring a voltage of a battery that drives the sound control device;
The first generation means includes
6. The sound control device according to claim 1, wherein the reference signal corresponding to the first sound signal is generated based on the voltage acquired by the third acquisition unit.

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