Control method of ceiling microphone

Abstract

To suppress a mistake of a speaker in a microphone installed to a ceiling.SOLUTION: A control method of a ceiling microphone, acquires a first sound signal collected by an array microphone constructed by a plurality of microphone elements, and a sound signal of an external part collected in a space that is different from that where a ceiling microphone exists, determines and outputs an output sound signal output by a speaker provided to a space similar to that where the ceiling microphone exists on the basis of the first sound signal and the sound signal of the external part to be acquired, stops control of a directional pattern of the array microphone constructed by the plurality of microphone elements collecting the sound of a speaker in the case of determining that there is the output sound signal to be output by the speaker, and fixes a sound collection direction where the sound of the speaker is collected.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present disclosure relates to a method for controlling a ceiling microphone.

Background Art

[0002] Patent Document 1 discloses a video conferencing method in which a mobile device is connected remotely in a video conferencing connection, the mobile device outputs remote video and remote audio received from the remote end via the video conferencing connection, and proximal video and proximal audio acquired using the mobile device are transmitted to the remote end via the video conferencing connection. In a wireless connection, the mobile device is connected to a video conferencing unit, and the video conferencing connection is transferred from the mobile device to the video conferencing unit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, when microphones of a plurality of mobile devices simultaneously capture sound, the microphone having the largest input volume is selected, and the sound of the selected microphone is used for video conferencing audio. Among the audio for video conferencing, the audio output from the speaker is removed by an echo canceller to remove the output audio. However, in the configuration of Patent Document 1, depending on the volume setting of the speaker, the positional relationship between the speaker and the microphones of each mobile device or the microphone array, etc., there is a possibility of misidentifying the speaker or deteriorating the transmitted sound quality due to the large output sound of the speaker included in the captured sound.

[0005] In view of the above-described conventional situation, the present disclosure has been devised, and an object thereof is to provide a method for controlling a ceiling microphone that suppresses misidentification of a speaker in a microphone installed on a ceiling.

Means for Solving the Problem

[0006] The present disclosure is a method for controlling a ceiling microphone performed by a ceiling microphone having a plurality of microphone elements capable of picking up the voice of a speaker. The method includes acquiring a first audio signal picked up by an array microphone composed of the plurality of microphone elements and an external audio signal picked up in a space different from the ceiling microphone, determining an output audio signal output by a speaker provided in the same space as the ceiling microphone based on the acquired first audio signal and the external audio signal, outputting the determined output audio signal to the speaker, and when it is determined that there is the output audio signal output by the speaker, stopping the control of the directivity of the array microphone that picks up the voice of the speaker and fixing the sound pickup direction for picking up the voice of the speaker. A method for controlling a ceiling microphone is provided.

[0007] These general or specific aspects may be implemented in a system, apparatus, method, integrated circuit, computer program, or recording medium, or may be implemented in any combination of a system, apparatus, method, integrated circuit, computer program, and recording medium.

Advantages of the Invention

[0008] According to the present disclosure, misidentification of a speaker in a microphone installed on the ceiling can be suppressed.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying out the Invention

[0010] Hereinafter, with appropriate reference to the drawings, each embodiment specifically disclosing the control method of the ceiling microphone according to the present disclosure will be described in detail. However, detailed descriptions that are more detailed than necessary may be omitted. For example, detailed descriptions of well-known matters and duplicate descriptions of substantially the same configurations may be omitted. This is to avoid making the following description unnecessarily redundant and to facilitate the understanding of those skilled in the art. Note that the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims thereby.

[0011] <Embodiment 1> First, with reference to FIG. 1, an example of the system configuration of the wireless microphone system 100 according to Embodiment 1 will be described. FIG. 1 is a diagram showing an example of the system configuration of the wireless microphone system 100 according to Embodiment 1.

[0012] The wireless microphone system 100 is provided, for example, in a conference room or a lecture hall where a meeting, a class, a lecture, or a training session attended by multiple people is held, as one base (referred to as "Base A" in FIG. 1). The wireless microphone system 100 includes a ceiling microphone CMC1, a wireless antenna unit WU1, wireless microphones MC11, MC12, an audio network ANW, a mixer MX, a power amplifier AMP, a speaker SPK, a terminal device P1, and a router RT.

[0013] Note that the wireless microphone system 100 may include a ceiling microphone CMC1, at least one microphone (e.g., wireless microphone MC11), at least one sound source (e.g., speaker SPK or terminal device P1, etc.), and an audio network ANW, and may be arbitrarily configured according to the usage purpose of the wireless microphone system 100. Also, the wireless microphone system 100 is shown as an example of being used for calls or meetings between multiple bases, but it may be used at a single base.

[0014] The ceiling microphone CMC1 is wired-connected between the wireless antenna unit WU1 and the audio network ANW to perform data transmission and reception. Here, the wired connection is, for example, a connection via a Local Area Network (hereinafter referred to as "LAN") cable or a Universal Serial Bus (hereinafter referred to as "USB") cable.

[0015] The ceiling microphone CMC1 is a so-called ceiling array microphone and is attached to the ceiling or the like. The ceiling microphone CMC1 includes a plurality of microphone elements MCE1,..., MCE64, and forms directivity toward the sound source by an array microphone composed of the plurality of microphone elements MCE1,..., MCE64, thereby picking up the sound generated from the sound source. Note that the ceiling microphone CMC1 in the first embodiment will be described as an example including 64 microphone elements MCE1,..., MCE64, but it goes without saying that the number of microphone elements included in the ceiling microphone CMC1 is not limited to this.

[0016] The ceiling microphone CMC1 is connected to the wireless antenna unit WU1 and acquires the audio signals picked up by the wireless microphones MC11 and MC12 via the wireless antenna unit WU1. Also, the ceiling microphone CMC1 acquires the audio signals of the sound picked up at other sites from the terminal device P1 via the mixer MX and the audio network ANW. The ceiling microphone CMC1 receives the inputs of the audio signals of the sound picked up by the array microphone composed of the microphone elements MCE1 to MCE64, the audio signals of the sound picked up by the wireless microphones MC11 and MC12, and the audio signals of the sound picked up at other sites, and executes the management of the output system of the audio signal output by the speaker SPK and the audio signal transmitted to other sites.

[0017] The ceiling microphone CMC1 determines the audio signal output by the speaker SPK among various audio signals, transmits it to the audio network ANW, and outputs it to the speaker SPK. Also, the ceiling microphone CMC1 determines the audio signal transmitted to other sites by the terminal device P1 among various audio signals and transmits it to the terminal device P1 via the audio network ANW.

[0018] The wireless antenna unit WU1 is wirelessly communicably connected to at least one of the wireless microphones MC11 and MC12 and transmits the audio signals picked up by the wireless microphones MC11 and MC12 to the ceiling microphone CMC1. Here, the wireless communication mentioned here is a wireless line conforming to the wireless communication standard of the time-division multiple access system (for example, the time-division multiplexing communication system). The wireless communication standard of the time-division multiplexing communication system will be described using, for example, the Digital Enhanced Cordless Telecommunication (DECT) system in the 1.9 GHz frequency band, which is the standard specification of digital cordless telephones formulated in 2011. However, it goes without saying that the wireless communication standard of the time-division multiplexing communication system does not have to be limited to DECT.

[0019] Wireless microphones MC11 and MC12 are portable devices that pick up the speaker's voice by being worn or held by the speaker. Wireless microphones MC11 and MC12 convert the picked-up voice into an audio signal and transmit it to the wireless antenna unit WU1.

[0020] The audio network ANW is communicably connected between the ceiling microphone CMC1, the mixer MX, and the power amplifier AMP. The audio network ANW is a so-called network hub that executes the transmission and reception of audio signals (audio data) executed between the ceiling microphone CMC1, the mixer MX, and the power amplifier AMP.

[0021] The mixer MX is communicably connected to the ceiling microphone CMC1 via the audio network ANW and communicably connected to the terminal device P1. The mixer MX acquires the audio signal of the voice picked up at the base A transmitted from the ceiling microphone CMC1 and the audio signal of the voice picked up at other bases transmitted from the terminal device P1. The mixer MX converts the acquired audio signal into a digital signal, adjusts the volume or sound quality, and transmits it to the ceiling microphone CMC1 and the terminal device P1.

[0022] The power amplifier AMP is communicably connected to the ceiling microphone CMC1 and the mixer MX via the audio network ANW. The power amplifier AMP amplifies the audio signal transmitted from the ceiling microphone CMC1 or the mixer MX to a level at which the speaker SPK can be driven and outputs it to the speaker SPK.

[0023] The speaker SPK converts the audio signal output from the power amplifier AMP into audio and outputs it. The speaker SPK outputs the voice picked up at its own base (i.e., base A) and the voice picked up at other bases.

[0024] The terminal device P1 is communicably connected between the mixer MX and the router RT. The terminal device P1 is realized by, for example, a Personal Computer (hereinafter referred to as "PC"), a notebook PC, a tablet terminal, a smartphone, etc., and enables data communication of voice signals, videos, etc. between its own base (i.e., base A) and other bases. Also, the terminal device P1 can receive user operations and execute settings such as the sound collection level of the ceiling microphone CMC1.

[0025] The router RT enables data communication between the terminal device P1 and a terminal device (not shown) of another base via the network NW.

[0026] The network NW is communicably connected to the routers RT installed at each base.

[0027] Next, with reference to FIG. 2, an internal configuration example of the ceiling microphone CMC1 will be described. FIG. 2 is a block diagram showing an internal configuration example of the ceiling microphone CMC1 in Embodiment 1. It goes without saying that the internal configuration of the ceiling microphone CMC1 shown in FIG. 2 is an internal configuration example when used for the usage shown in FIG. 1, and is not limited thereto.

[0028] The ceiling microphone CMC1 includes a microphone input unit 11, a sound source position estimation unit 12, an external audio input unit 13, a sound amplification detection unit 14, a directivity control unit 15, an audio signal processing unit 16, an external audio input unit 17, a wireless microphone input unit 18, a level detection unit 19, a level attenuation unit 20, an output channel selection unit 21, and a memory 22.

[0029] The microphone input unit 11 receives the input of the audio signal of the sound collected by the array microphone composed of the microphone elements MCE1,..., MCE64 provided in the ceiling microphone CMC1. The microphone input unit 11 outputs the audio signal input from the array microphone composed of the microphone elements MCE1,..., MCE64 to each of the sound source position estimation unit 12 and the directivity control unit 15.

[0030] The sound source position estimation unit 12 estimates the sound source position based on the audio signals picked up by the array microphone composed of the microphone elements MCE1, …, MCE64. The sound source position estimation unit 12 outputs the information on the estimated sound source position to the directivity control unit 15.

[0031] The external audio input unit 13 receives the input of the audio signal (speaker audio) output from the audio network ANW and output from the speaker SPK. The external audio input unit 13 outputs the input audio signal to the sound amplification detection unit 14.

[0032] The sound amplification detection unit 14 detects the amplified voice in the space (for example, a conference room or a lecture hall, etc.) where the ceiling microphone CMC1 is installed based on the audio signal (speaker audio) output from the external audio input unit 13. The sound amplification detection unit 14 outputs the audio signal (speaker audio) and the information on the detection result of whether there is amplified voice to the directivity control unit 15.

[0033] The directivity control unit 15 controls the directivity of the array microphone composed of the microphone elements MCE1, …, MCE64 based on the audio signal output from the microphone input unit 11, the estimated position of the sound source output from the sound source position estimation unit 12, and the detection result output from the sound amplification detection unit 14. When no amplified voice is detected, the directivity control unit 15 controls the directivity of the array microphone composed of the microphone elements MCE1, …, MCE64 to face the sound source position. When amplified voice is detected, the directivity control unit 15 stops controlling the directivity of the array microphone composed of the microphone elements MCE1, …, MCE64 or controls the directivity so as not to face the speaker SPK. The directivity control unit 15 outputs the audio signal output from the microphone input unit 11 to the audio signal processing unit 16.

[0034] The audio signal processing unit 16 performs audio processing on the audio signal output from the directivity control unit 15 and outputs it to the level attenuation unit 20.

[0035] The external audio input unit 17 receives the input of the audio signals of the wireless microphones input to other ceiling microphones installed at the same site. Although not shown in FIG. 1, a plurality of ceiling microphones may be installed at the same site. An example in which a plurality of ceiling microphones are installed at the same site will be described in detail in Embodiment 2.

[0036] The wireless microphone input unit 18 receives the input of the audio signals transmitted from the wireless antenna unit WU1 and picked up by the wireless microphones MC11 and MC12 respectively. The wireless microphone input unit 18 outputs the input audio signals to the level detection unit 19. The wireless antenna unit WU1 receives the audio signals picked up by the wireless microphones MC11 and MC12 respectively by the microphone audio reception unit WU11, and transmits the audio signals to the level detection unit 19 and the output channel selection unit 21 respectively.

[0037] The level detection unit 19 acquires the audio signals of the wireless microphones input to other ceiling microphones (not shown) and the audio signals picked up by the wireless microphones MC11 and MC12 respectively. Based on whether the signal level of the acquired audio signal is equal to or higher than a predetermined level, the level detection unit 19 detects whether there is audio input to other ceiling microphones (not shown) by the wireless microphones or audio picked up by the wireless microphones MC11 and MC12 respectively. The level detection unit 19 outputs the acquired audio signal and the information of the detection result to the level attenuation unit 20. Also, the level attenuation unit 20 outputs the audio signal output from the external audio input unit 17 to the output channel selection unit 21.

[0038] The level attenuation unit 20 acquires the audio signal output from the audio signal processing unit 16 (i.e., the audio signal picked up by the array microphone composed of the microphone elements MCE1, …, MCE64) and the audio detection presence / absence information output from the level detection unit 19 (i.e., information on whether there is audio from a wireless microphone input to another ceiling microphone or audio picked up by each of the wireless microphones MC11 and MC12). Based on the acquired audio detection presence / absence information, the level attenuation unit 20 adjusts the pickup level of the audio picked up by the array microphone composed of the microphone elements MCE1, …, MCE64 of the ceiling microphone CMC1. The level attenuation unit 20 outputs the audio signal output from the audio signal processing unit 16 (i.e., the audio signal picked up by the array microphone composed of the microphone elements MCE1, …, MCE64) to the output channel selection unit 21.

[0039] The output channel selection unit 21 acquires each audio signal output from the wireless microphone input unit 18 and the level attenuation unit 20. Based on the acquired audio signals, the output channel selection unit 21 selects the audio signal output from the speaker SPK, and transmits it to the power amplifier AMP via the audio network ANW to output it to the speaker SPK.

[0040] Also, the output channel selection unit 21 transmits the audio signals picked up by the ceiling microphone CMC1 and the wireless microphones MC11 and MC12 installed at its own base (i.e., base A) to other bases by transmitting them to the mixer MX and the terminal device P1 via the audio network ANW.

[0041] The memory 22 has, for example, a Random Access Memory (RAM) as a work memory used when executing each process of the ceiling microphone CMC1, and a Read Only Memory (ROM) that stores a program and data defining the operation of the ceiling microphone CMC1. In the RAM, data or information generated or acquired by the ceiling microphone CMC1 is temporarily stored. In the ROM, a program defining the operation of the ceiling microphone CMC1 is written. The memory 22 stores information for controlling the sound collection levels of the array microphones composed of the microphone elements MCE1, …, MCE64.

[0042] <Embodiment 2> The wireless microphone system 100 according to Embodiment 1 showed an example in which one ceiling microphone CMC1 is installed at one base. The wireless microphone system 100A according to Embodiment 2 will describe an example in which a plurality of ceiling microphones CMC1 are installed at one base.

[0043] In the description of the wireless microphone system 100A according to Embodiment 2, for the same configurations and functions as those of the wireless microphone system 100 according to Embodiment 1, the same reference numerals are given and the description thereof is omitted.

[0044] Referring to FIG. 3, a system configuration example of the wireless microphone system 100A according to Embodiment 2 will be described. FIG. 3 is a diagram showing a system configuration example of the wireless microphone system 100A according to Embodiment 2.

[0045] The wireless microphone system 100A is provided, for example, in a conference room or a lecture hall where meetings, classes, lectures, training sessions, etc. attended by multiple people are held, as one base (referred to as "Base A" in FIG. 3). The wireless microphone system 100A includes a plurality of ceiling microphones CMC1 and CMC2, a plurality of wireless antenna units WU1 and WU2, wireless microphones MC11, MC12, MC21, and MC22, an audio network ANW, a mixer MX, a power amplifier AMP, a speaker SPK, a terminal device P1, and a router RT. Note that the wireless microphone system 100A may include three or more ceiling microphones.

[0046] The ceiling microphone CMC1 is connected to be capable of transmitting and receiving data to and from the ceiling microphone CMC2, the mixer MX, and the power amplifier AMP via the audio network ANW.

[0047] The ceiling microphone CMC2 is wired-connected between the wireless antenna unit WU2 and the audio network ANW to perform data transmission and reception. The ceiling microphone CMC2 is connected to be capable of transmitting and receiving data to and from the ceiling microphone CMC1, the mixer MX, and the power amplifier AMP via the audio network ANW. Here, the so-called wired connection is, for example, a connection via a LAN cable or a USB cable.

[0048] The ceiling microphone CMC2 has the same configuration as the ceiling microphone CMC1. The ceiling microphone CMC2 is a so-called ceiling array microphone and is attached to the ceiling or the like. The ceiling microphone CMC2 includes a plurality of microphone elements MCE1,..., MCE64, and forms directivity toward the sound source by the array microphone composed of the microphone elements MCE1,..., MCE64 to pick up the sound generated from the sound source. Note that, in the second embodiment, the ceiling microphone CMC2 is described as an example including 64 microphone elements MCE1,..., MCE64, but it goes without saying that the number of microphone elements included in the ceiling microphone CMC2 is not limited to this.

[0049] The ceiling microphone CMC2 is connected to the wireless antenna unit WU2 and acquires the voice signals picked up by the wireless microphones MC21 and MC22 via the wireless antenna unit WU2. Also, the ceiling microphone CMC2 acquires the voice signals of the voices picked up at other sites from the terminal device P1 via the mixer MX and the audio network ANW. The ceiling microphone CMC2 receives the inputs of the voice signals of the voices picked up by the array microphone composed of the microphone elements MCE1, …, MCE64, the voice signals of the voices picked up by the wireless microphones MC21 and MC22, and the voice signals of the voices picked up at other sites, and executes the management of the output system of the voice signals output by the speaker SPK and the voice signals transmitted to other sites.

[0050] The ceiling microphone CMC2 determines the voice signals output by the speaker SPK among the various voice signals, transmits them to the audio network ANW, and outputs them to the speaker SPK. Also, the ceiling microphone CMC2 determines the voice signals transmitted to other sites by the terminal device P1 among the various voice signals and transmits them to the terminal device P1 via the audio network ANW.

[0051] The wireless antenna unit WU2 is wirelessly communicably connected to at least one of the wireless microphones MC21 and MC22 and transmits the voice signals picked up by the wireless microphones MC21 and MC22 to the ceiling microphone CMC2. Here, the wireless communication mentioned here is a wireless line conforming to the wireless communication standard of the time-division multiple access system (for example, the time-division multiplexing system).

[0052] The wireless microphones MC21 and MC22 are portable devices that pick up the voice of the speaker by being worn or held by the speaker. The wireless microphones MC21 and MC22 convert the picked-up voice into a voice signal and transmit it to the wireless antenna unit WU2.

[0053] The audio network ANW is communicably connected between the ceiling microphones CMC1 and CMC2, the mixer MX, and the power amplifier AMP. The audio network ANW is a so-called network hub that executes transmission and reception of audio signals (audio data) performed between the ceiling microphones CMC1 and CMC2, the mixer MX, and the power amplifier AMP.

[0054] Next, with reference to FIG. 4, an internal configuration example of the ceiling microphones CMC1 and CMC2 will be described. FIG. 4 is a block diagram showing an internal configuration example of the ceiling microphones CMC1 and CMC2 in Embodiment 2. Note that the internal configuration of the ceiling microphones CMC1 and CMC2 shown in FIG. 4 is an internal configuration example when used for the usage shown in FIG. 2, and it goes without saying that it is not limited thereto.

[0055] The ceiling microphone CMC1 includes a microphone input unit 11, a sound source position estimation unit 12, an external audio input unit 13, a sound amplification detection unit 14, a directivity control unit 15, an audio signal processing unit 16, an external audio input unit 17A, a wireless microphone input unit 18, a level detection unit 19, a level attenuation unit 20, an output channel selection unit 21, and a memory 22.

[0056] The external audio input unit 17A receives the input of audio signals picked up by the wireless microphones MC21 and MC22, which are received by the wireless antenna unit WU2 connected to another ceiling microphone CMC2 installed at the same base.

[0057] The ceiling microphone CMC2 includes a microphone input unit 11, a sound source position estimation unit 12, an external audio input unit 13, a sound amplification detection unit 14, a directivity control unit 15, an audio signal processing unit 16, an external audio input unit 17B, a wireless microphone input unit 18, a level detection unit 19, a level attenuation unit 20, an output channel selection unit 21, and a memory 22.

[0058] The external audio input unit 17B receives the input of the audio signals picked up by the wireless microphones MC11 and MC12, which are received by the wireless antenna unit WU1 connected to another ceiling microphone CMC1 installed at the same site.

[0059] The wireless microphone input unit 18B receives the input of the audio signals picked up by the wireless microphones MC21 and MC22, which are transmitted from the wireless antenna unit WU2. The wireless microphone input unit 18B outputs the input audio signals to the level detection unit 19. The wireless antenna unit WU2 receives the audio signals picked up by the wireless microphones MC21 and MC22 by the microphone audio reception unit WU21, and transmits the audio signals to the level detection unit 19 and the output channel selection unit 21 respectively.

[0060] When a plurality of ceiling microphones are installed at the same site, these ceiling microphones may be set as a master ceiling microphone that determines the audio signals output by the speaker among all the wireless microphones, all the array microphones, and the audio signals transmitted from other sites, and a slave ceiling microphone that transmits the audio signals picked up by the wireless microphones and the array microphones to the master ceiling microphone and does not determine the audio signals output by the speaker.

[0061] Next, with reference to FIG. 5, the control of the ceiling microphones CMC1 and CMC2 will be described. FIG. 5 is a flowchart showing an example of the procedure for adjusting the sound pickup levels of the ceiling microphones CMC1 and CMC2 in the first and second embodiments. The example of the procedure for adjusting the sound pickup levels shown in FIG. 5 is executed by each ceiling microphone. Here, for the sake of easy understanding, the example of the procedure for adjusting the sound pickup levels executed by the ceiling microphone CMC1 will be described, but the same applies to the ceiling microphone CMC2.

[0062] The ceiling microphone CMC1 receives the input of the audio signals of the voices picked up by each of the wireless microphones MC11 and MC12 (St11). The ceiling microphone CMC1 determines whether there are audio signals input from each of the wireless microphones within the same base, that is, the wireless microphones MC11 and MC12, or the wireless microphones MC21 and MC22 (St12).

[0063] When the ceiling microphone CMC1 determines that there are audio signals input from the wireless microphones within the same base (St12, YES), the ceiling microphone CMC1 executes control to attenuate the pickup level of the array microphone composed of the microphone elements MCE1,..., MCE64 of the ceiling microphone CMC1 to a predetermined pickup level set in advance (St13).

[0064] When the ceiling microphone CMC1 determines that there are no audio signals input from the wireless microphones within the same base (St12, NO), the ceiling microphone CMC1 omits the control to attenuate the pickup level of the array microphone composed of the microphone elements MCE1,..., MCE64 of the ceiling microphone CMC1 (St14). Note that when the current pickup level of the ceiling microphone CMC1 has been attenuated to the predetermined pickup level, the ceiling microphone CMC1 may execute control to return (amplify) the pickup level to the pickup level before attenuation.

[0065] As described above, in Embodiments 1 and 2, when audio signals are input from the wireless microphones installed within their own bases, the ceiling microphones CMC1 and CMC2 can output the audio signals of the wireless microphones preferentially from the speaker SPK or transmit them to other bases by attenuating the pickup levels of the ceiling microphones CMC1 and CMC2. Thereby, the ceiling microphones CMC1 and CMC2 in Embodiments 1 and 2 can improve the sound quality of the audio signals output from the speaker SPK or transmitted to other bases.

[0066] Next, with reference to FIG. 6, the control of the ceiling microphones CMC1 and CMC2 will be described. FIG. 6 is a flowchart showing an example of a procedure for adjusting the directivity of the ceiling microphones CMC1 and CMC2 in Embodiments 1 and 2. The example of the procedure for adjusting the sound collection level shown in FIG. 6 is executed by each ceiling microphone. Here, for the sake of easy understanding, an example of the procedure for adjusting the sound collection level executed by the ceiling microphone CMC1 will be described, but the same applies to the ceiling microphone CMC2.

[0067] The ceiling microphone CMC1 receives, as an external sound, the input of an audio signal (speaker audio) output from a speaker SPK installed at its own base (St21). The ceiling microphone CMC1 determines whether there is amplified sound based on the input audio signal (St22).

[0068] When the ceiling microphone CMC1 determines that there is amplified sound (St22, YES), the control of the directivity of the array microphone composed of the microphone elements MCE1,..., MCE64 of the ceiling microphone CMC1 is stopped, or the directivity of the array microphone is controlled so as not to face the speaker SPK, thereby fixing the sound collection direction (St23).

[0069] On the other hand, when the ceiling microphone CMC1 determines that there is no amplified sound (St22, NO), the control of the directivity of the array microphone composed of the microphone elements MCE1,..., MCE64 of the ceiling microphone CMC1 is enabled, the position of the sound source (i.e., the speaker) is estimated, and the directivity of the array microphone is formed at the estimated position of the speaker (St24).

[0070] As described above, in Embodiments 1 and 2, when sound is output from the speaker SPK installed within the own base, the ceiling microphones CMC1 and CMC2 can more effectively suppress the misrecognition of the sound output from the speaker SPK as the sound source (speaker) by stopping the formation of the directivity of the ceiling microphones CMC1 and CMC2 or controlling the directivity so as not to face the speaker SPK. As a result, the ceiling microphones CMC1 and CMC2 can improve the sound quality of the audio signal output from the speaker SPK or transmitted to other bases.

[0071] (Supplementary Note) From the description of the above embodiments, the following technologies are disclosed.

[0072] (Technology 1) A control method for a ceiling microphone CMC1 having a plurality of microphone elements MCE1 to MCE64 capable of picking up the voice of a speaker, acquiring a first audio signal picked up by an array microphone composed of the plurality of microphone elements MCE1 to MCE64 and an external audio signal picked up in a space different from the ceiling microphone CMC1, determining an output audio signal output by a speaker SPK provided in the same space as the ceiling microphone CMC1 based on the acquired first audio signal and the external audio signal, outputting the determined output audio signal to the speaker SPK, and when it is determined that there is the output audio signal output by the speaker SPK, stopping the control of the directivity of the array microphone that picks up the voice of the speaker or controlling the directivity so as not to face the speaker SPK, thereby fixing the sound pickup direction for picking up the voice of the speaker. A control method for the ceiling microphone CMC1. With this configuration, the ceiling microphone CMC1 misidentifies the voice output from the speaker SPK provided in the same space, that is, the same base, as the voice of the speaker, and can more effectively suppress the formation of the directivity of the array microphone composed of the microphone elements MCE1 to MCE64 toward the position of the speaker SPK.

[0073] (Technology 2) When it is determined that there is no output of the output audio signal output by the speaker SPK, enabling the control of the directivity of the array microphone that picks up the voice of the speaker, estimating the direction of the speaker based on the first audio signal, forming the directivity of the array microphone in the estimated direction of the speaker. The control method for the ceiling microphone CMC1 according to (Technology 1). With this configuration, when the ceiling microphone CMC1 does not receive audio output from the speaker SPK provided in the same space, i.e., the same base, it estimates the position of the speaker at the same base and forms the directivity of the array microphone composed of a plurality of microphone elements MCE1 to MCE64 toward the estimated speaker position, thereby enabling more effective sound collection of the speaker's voice.

[0074] (Technology 3) The ceiling microphone CMC1 is further communicably connected to at least one first microphone (wireless microphones MC11, MC12) provided in the same space as the ceiling microphone CMC1, and further receives the input of the second audio signal picked up by the first microphone (wireless microphones MC11, MC12), and based on the first audio signal, the second audio signal, and the external audio signal, determines the output audio signal output by the speaker SPK. When it is determined that there is an input of the second audio signal, the sound collection level of the sound picked up by the array microphone is attenuated to a predetermined sound collection level. The control method of the ceiling microphone CMC1 according to (Technology 1) or (Technology 2). With this configuration, when the voices of the speaker are picked up by the wireless microphones MC11 and MC12 provided in the same space, i.e., the same base, the ceiling microphone CMC1 can preferentially transmit the voices picked up by the wireless microphones MC11 and MC12 to other bases by attenuating the sound collection level of the ceiling microphone CMC1. Thereby, the ceiling microphone CMC1 can transmit high-quality voices to other bases.

[0075] (Technology 4) When it is determined that there is no input of the second audio signal, the sound collection level of the sound picked up by the array microphone is amplified to the sound collection level before attenuation. The control method of the ceiling microphone CMC1 according to any one of (Technology 1) to (Technology 3). With this configuration, when the ceiling microphone CMC1 does not pick up the speaker's voice by the wireless microphones MC11 and MC12 provided in the same space, that is, the same base, the ceiling microphone CMC1 can more effectively pick up the voice within the base by returning the pickup level to the pickup level before attenuation.

[0076] (Technology 5) The ceiling microphone CMC1 is further communicably connected to another ceiling microphone CMC2 provided in the same space, and further receives the input of a third audio signal picked up by at least one second microphone (wireless microphones MC21 and MC22) communicably connected to the other ceiling microphone CMC2, and based on the first audio signal, the second audio signal, the third audio signal, and the external audio signal, determines the output audio signal output by the speaker SPK. When it is determined that there is an input of the third audio signal, the pickup level of the audio picked up by the array microphone is attenuated to a predetermined pickup level. The control method of the ceiling microphone CMC1 according to any one of (Technology 1) to (Technology 4). With this configuration, when the ceiling microphone CMC1 does not pick up the speaker's voice by the wireless microphones MC21 and MC22 provided in the same space, that is, the same base, the ceiling microphone CMC1 can more effectively pick up the voice within the base by returning the pickup level to the pickup level before attenuation.

[0077] (Technology 6) When it is determined that there is no input of the third audio signal, the pickup level of the array microphone is amplified to the pickup level before attenuation. The control method of the ceiling microphone CMC1 according to any one of (Technology 1) to (Technology 5). With this configuration, when the ceiling microphone CMC1 does not pick up the voice of the speaker by the wireless microphones MC11 and MC12 provided in the same space, that is, the same base, the ceiling microphone CMC1 can pick up the voice in the base more effectively by returning the pickup level to the pickup level before attenuation.

[0078] As described above, the embodiments have been described with reference to the accompanying drawings, but the present disclosure is not limited to such examples. It is obvious that those skilled in the art can conceive various modification examples, correction examples, substitution examples, addition examples, deletion examples, and equivalent examples within the scope described in the claims, and it is understood that those also belong to the technical scope of the present disclosure. Further, within the scope not departing from the gist of the invention, the components in the above-described embodiments may be arbitrarily combined.

Industrial Applicability

[0079] The present disclosure is useful as a method for controlling a ceiling microphone that suppresses misidentification of a speaker in a microphone installed on a ceiling.

Explanation of Signs

[0080] 11 Microphone input section 12 Sound source position estimation section 13 External audio input section 14 Loud voice detection section 15 Directivity control section 16 Audio signal processing section 17, 17A, 17B External audio input section 18, 18B Wireless microphone input section 19 Level detection section 20 Level attenuation section 21 Output channel selection section 100, 100A Wireless microphone system AMP Power amplifier MC11, MC12, MC21, MC22 Wireless microphones MCE1, MCE64 Microphone elements MX Mixer NW Network ANW Audio Network P1 Terminal Device CMC1, CMC2 Ceiling Microphone SPK Speaker WU1, WU2 Wireless Antenna Unit WU11, WU21 Microphone Audio Receiver

Claims

1. A method for controlling a ceiling microphone performed by a ceiling microphone having a plurality of microphone elements capable of collecting the voice of a speaker, obtaining a first audio signal collected by an array microphone composed of the plurality of microphone elements and an external audio signal collected in a space different from the ceiling microphone, determining an output audio signal output by a speaker provided in the same space as the ceiling microphone based on the obtained first audio signal and the external audio signal, outputting the determined output audio signal to the speaker, and when it is determined that there is the output audio signal output by the speaker, stopping the control of the directivity of the array microphone that collects the voice of the speaker and fixing the sound collection direction for collecting the voice of the speaker, A method for controlling a ceiling microphone.

2. When it is determined that there is no output of the output audio signal output by the speaker, enabling the control of the directivity of the array microphone that collects the voice of the speaker, estimating the direction of the speaker based on the first audio signal, forming the directivity of the array microphone in the estimated direction of the speaker, The method for controlling a ceiling microphone according to Claim 1.

3. The ceiling microphone is further communicably connected to at least one first microphone provided in the same space as the ceiling microphone, and further receives an input of a second audio signal collected by the first microphone, and based on the first audio signal, the second audio signal, and the external audio signal, determining the output audio signal output by the speaker, When it is determined that there is an input of the second audio signal, attenuating the sound collection level of the sound collected by the array microphone to a predetermined sound collection level, The method for controlling a ceiling microphone according to Claim 1.

4. When it is determined that there is no input of the second audio signal, the sound collection level of the sound collected by the array microphone is amplified to the sound collection level before attenuation. The ceiling microphone control method according to claim 3.

5. It is further communicably connected between the ceiling microphone and another ceiling microphone provided in the same space, and a third audio signal collected by at least one second microphone communicably connected to the other ceiling microphone is received. Based on the first audio signal, the second audio signal, the third audio signal, and the external audio signal, the output audio signal output by the speaker is determined. When it is determined that there is an input of the third audio signal, the sound collection level of the sound collected by the array microphone is attenuated to a predetermined sound collection level. The ceiling microphone control method according to claim 3.

6. When it is determined that there is no input of the third audio signal, the sound collection level of the array microphone is amplified to the sound collection level before attenuation. The ceiling microphone control method according to claim 5.

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