JP2015211303A - Voice collection system and voice reproduction system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve microphone array processing or speaker array processing by adding an acoustic device as required.SOLUTION: A client unit 3k includes a voice acquisition unit for transmitting an acoustic signal, generated based on a collected voice, to a host unit 1, and a connection control unit for transmitting a connection request to the host unit 1. The host unit 1 includes a voice acquisition unit 12 for generating an acoustic signal on the basis of a collected voice, a microphone array control unit 16 outputting a processed acoustic signal, subjected to a desired microphone array processing, by using an acoustic signal outputted from the voice acquisition unit 12, and an acoustic signal received from the client unit 3k, and a connection control unit 10 for receiving the connection request and adding the client unit 3k to the microphone array control unit 16.

Description

  The present invention relates to a sound collection and reproduction technique for reproducing a collected sound by performing acoustic processing such as noise suppression, sound enhancement, and area reproduction using a plurality of acoustic devices including microphones and speakers.

  Conventionally, there has been a technology for performing an audio conference using a microphone with a camera function attached to a television (see Non-Patent Documents 1, 2, and 3). In the audio conference technology described in Non-Patent Documents 1 and 2, it is possible to pick up the voice spoken by a speaker near the microphone with a camera function with a quality suitable for the service, but the speaker has a camera function. There is a problem that the sound collection quality of the speech spoken far away from the microphone deteriorates.

  In order to solve this problem, the communication terminal described in Non-Patent Document 3 can be used as an extension microphone by connecting the audio device described in Non-Patent Document 4 with a USB (Universal Serial Bus) cable. . As a result, by extending the USB cable, it is possible to pick up the voice of the speaker far from the camera-equipped microphone. In addition, the acoustic device described in Non-Patent Document 4 also has a speaker function, and can assist the speaker included in the communication terminal described in Non-Patent Document 3.

East Nippon Telegraph and Telephone Corporation, “Hikari Share Place”, [online], [Search April 14, 2014], Internet <URL: https://web116.jp/shop/goods/hlv1-tel/hlv1-tel_00 .html> West Nippon Telegraph and Telephone Corporation, “Hikari Danran TV”, [online], [Search April 14, 2014], Internet <URL: http://flets-w.com/hikaridenwa/danlan/> Nippon Telegraph and Telephone West Corporation, “HLV1-TEL Instruction Manual”, [online], [Search April 14, 2014], Internet <URL: https://www.ntt-west.co.jp/kiki/ download / reflection / danlan / HLV1-TEL_man3.pdf> NTT Advanced Technology Corporation, “R-Talk Instruction Manual”, [online], [Search April 14, 2014], Internet <URL: http://www.ntt-at.co .jp / product / rt800 / pdf / rt800_manual.pdf>

  In order to expand the microphone and the speaker in the communication terminal described in Non-Patent Document 3, a dedicated device such as the acoustic device described in Non-Patent Document 4 is required. In addition, since the audio device described in Non-Patent Document 4 needs to be connected by a wire such as a USB cable, when a new audio device is added to an existing communication terminal, the hardware is remodeled or redesigned. There is a need.

  An object of the present invention is to realize a sound collecting and reproducing technique for performing microphone array processing and speaker array processing by adding an acoustic device having a microphone function and a speaker function as necessary.

  In order to solve the above-described problem, the sound pickup system according to the first aspect of the present invention includes a host unit and at least one client unit. The client unit includes an audio acquisition unit that transmits an acoustic signal generated based on collected sound to the host unit, and a connection control unit that transmits a connection request to the host unit. The host unit uses a voice acquisition unit that generates an acoustic signal based on the collected voice, an acoustic signal output from the voice acquisition unit of the host unit, and an acoustic signal received from the client unit, to obtain a desired microphone array A microphone array control unit that outputs a processed acoustic signal after processing, and a connection control unit that receives a connection request and adds a client unit to the microphone array control unit.

  The audio reproduction system according to the second aspect of the present invention includes a host unit and at least one client unit. The client unit includes a connection control unit that transmits a connection request to the host unit, and an audio playback unit that plays back the processed acoustic signal received from the host unit. The host unit outputs a processed acoustic signal obtained by performing desired speaker array processing on the input acoustic signal, and transmits the acoustic signal to the client unit, and audio for reproducing the processed acoustic signal. A reproduction unit; and a connection control unit that receives the connection request and adds the client unit to the speaker array control unit.

  According to the present invention, it is possible to realize a sound collecting / reproducing technology for performing microphone array processing and speaker array processing by adding an acoustic device having a microphone function and a speaker function as necessary. For example, by using a smartphone having a wireless communication function such as a wireless local area network (LAN) as an acoustic device, a microphone or a speaker can be connected to a microphone array as necessary without using a wired connection. Can be added to speaker array processing.

FIG. 1 is a diagram exemplifying a functional configuration of the sound collecting / reproducing system. FIG. 2 is a diagram illustrating a functional configuration of the host unit. FIG. 3 is a diagram illustrating a functional configuration of the client unit. FIG. 4 is a diagram illustrating an input interface of the client unit. FIG. 5 is a diagram exemplifying a processing flow of the sound collecting / reproducing method.

  Hereinafter, embodiments of the present invention will be described in detail. In addition, the same number is attached | subjected to the component which has the same function in drawing, and duplication description is abbreviate | omitted.

  The voice recording / reproducing technique of the present invention is composed of processing of a host unit and processing of a client unit. The processing of the host unit aggregates the voices sent from the client unit and emphasizes only specific voices by performing asynchronous voice processing. The host unit performs asynchronous audio processing and performs acoustic processing on a signal obtained by separating audio for each speaker near the client unit in accordance with the audio service to be used. For example, in the case of a voice call, automatic gain control (AGC: Automatic Gain Control) for adjusting the volume for each speaker is performed, and then mixed and transmitted to another point.

  In the present invention, sound collection in a wider range is realized by connecting the host unit and the client unit by wireless communication such as wireless LAN. In addition, by connecting a client unit having a speaker function, the speaker can be easily and wirelessly linked.

  The range of the wireless LAN can reach radio waves only in a relatively narrow area with a single access point, but if the wireless LAN is within the range, the voice of all speakers can be picked up by adding a client unit. Can function properly as a voice recording and playback service.

Speech sound collecting and reproducing system 5 in the embodiment, as shown in FIG. 1, the host unit 1 and K (> 1) number of the client unit 3 _1, ..., including 3 _K, for example. The sound pickup / playback system 5 realizes a sound pickup / playback function by linking at least two sets. In this embodiment, a case where there are two sets of the sound collecting / reproducing systems 5 will be described as an example, but a configuration in which three or more sets of sound collecting / reproducing systems 5 are used to reproduce sounds in which three or more spaces are collected from each other. It is also possible.

As shown in FIG. 1, when implementing the voice sound pickup reproducing function by the audio sound collecting and reproducing system 5 _A and the audio sound collecting and reproducing system 5 _B, the client unit 3 _first speech sound collecting and reproducing system 5 _A, ..., 3 _K , And the space where the client units 3 ₁ ,..., 3 _{K of the} audio recording and reproducing system 5 _B are arranged are different spaces.

The host unit 1 of the sound pickup / playback system 5 _{A and} the host unit 1 of the sound pickup / playback system 5 _B are both connected to the communication network 9. The communication network 9 only needs to be configured so that connected devices can communicate with each other. For example, the Internet, a WAN (Wide Area Network), a LAN (Local Area Network), a public switched telephone network, a dedicated line, etc. Can be configured.

It may be the same as the number of clients 3 included in the number of clients 3 and the audio sound collecting and reproducing system 5 _B included in the audio sound collecting and reproducing system 5 _A, may be different.

  As shown in FIG. 2, the host unit 1 includes a microphone M, a speaker S, a connection control unit 10, a screen control unit 11, a voice acquisition unit 12, a packet reception unit 13, an echo canceller unit 14, a signal buffer unit 15, and a microphone array. For example, it includes a control unit 16, a voice service processing unit 17, a speaker array control unit 18, a packet transmission unit 19, and a voice acquisition unit 20.

  The host unit 1 has a special configuration in which a special program is read into a known or dedicated computer having a central processing unit (CPU), a main storage (RAM), and the like. Device. For example, the host unit 1 executes each process under the control of the central processing unit. The data input to the host unit 1 and the data obtained in each process are stored in, for example, a main storage device, and the data stored in the main storage device is read out as needed and used for other processes. The Further, at least a part of each processing unit of the host unit 1 may be configured by hardware such as an integrated circuit.

  As shown in FIG. 3, the client unit 3 includes, for example, a microphone M, a speaker S, a connection control unit 30, a screen control unit 31, an audio acquisition unit 32, a packet transmission unit 33, a packet reception unit 34, and an audio reproduction unit 35. .

  For example, the client unit 3 is a special unit configured by reading a special program into a known or dedicated computer having a central processing unit (CPU), a main storage (RAM), and the like. Device. For example, the client unit 3 executes each process under the control of the central processing unit. The data input to the client unit 3 and the data obtained in each process are stored in, for example, the main storage device, and the data stored in the main storage device is read out as necessary and used for other processes. The In addition, at least a part of each processing unit of the client unit 3 may be configured by hardware such as an integrated circuit.

  The client unit 3 is preferably an acoustic device having a wireless communication function such as a wireless communication network such as a wireless LAN, or a short-range wireless communication such as Bluetooth (registered trademark) or NFC (Near Field Connection). Specifically, the client unit 3 is, for example, a smartphone, a tablet terminal, an existing video conference device or audio conference device, a TV, a remote control of a TV having a microphone or a speaker, a laptop type with a built-in or external microphone or speaker. Alternatively, a desktop personal computer, a stationary video game machine, a controller of a video game machine, a portable game machine, or the like.

  The client unit 3 has an input interface using a screen. For example, the input interface of the client unit 3 can be implemented as an application having a user interface as shown in FIG. FIG. 4A shows an example of a state in which the client unit 3 is disconnected from the host unit 1. FIG. 4B shows an example of a state in which the client unit 3 is connected to the host unit 1 and the microphone can be used. FIG. 4C shows an example of a state where the client unit 3 is performing an operation for connecting to the host unit 1.

  When the client unit 3 is mounted by a general-purpose information processing device such as a smartphone, it is necessary to install a program (hereinafter referred to as an application) in which the client unit 3 is mounted on the smartphone. As an application distribution method, distribution of applications using a digital content distribution service provided by a smartphone manufacturer or a mobile communication company can be used. A method of installing an application built in the host unit 1 by the client unit 3 accessing the host unit 1 is also possible. As a method of accessing the host unit 1, for example, as described above, wireless LAN, Bluetooth (registered trademark), NFC, or the like can be used. In addition to acquiring an application from the host unit 1, each client unit 3 can also share and introduce an application. As an access method between the client units 3, for example, infrared communication or NFC can be used.

  With reference to FIG. 5, the audio | voice sound collection reproduction | regeneration method of embodiment is demonstrated.

  In step S <b> 30, the connection control unit 30 of the client unit 3 performs connection control between the client unit 3 and the host unit 1. In order for the client unit 3 to connect to the host unit 1, it is first necessary to specify the IP address of the host unit 1 that is the connection destination. As the IP address of the connection destination, for example, the IP address received from the screen control unit 31 is used as the connection destination. Alternatively, the IP address of the host unit 1 is fixed and determined. Alternatively, a method in which the client unit 3 searches for the host unit 1 that is the connection destination can be used.

  The method for the client unit 3 to search for the host unit 1 to be connected can be, for example, the following method. First, a start signal is input from the screen control unit 31 of the client unit 3 by a user operation. The connection control unit 30 of the client unit 3 broadcasts a request packet in the wireless LAN to which the client unit 3 is connected. When there is a host unit 1 that can react to the broadcast packet, the connection control unit 10 of the host unit 1 returns a response packet. The connection control unit 30 of the client unit 3 determines the IP address written in the reply packet as the IP address of the host unit 1 that is the connection destination.

  The connection control unit 30 of the client unit 3 can also authenticate the user to the connection destination host unit 1. For example, in the case of authentication using a PIN (Personal Identification Number) code, the connection control unit 30 of the client unit 3 transmits the PIN code received from the screen control unit 31 to the connection control unit 10 of the host unit 1. The connection control unit 10 of the host unit 1 compares the PIN code generated by the host unit 1 with the received PIN code. If the authentication is successful, a packet indicating approval is returned. If the authentication is unsuccessful, the connection is rejected. Returns the packet indicated. When receiving a packet indicating approval, the connection control unit 30 of the client unit 3 establishes a connection with the host unit 1 and when receiving a packet indicating connection refusal, instructs the packet transmission unit 33 to stop packet transmission. Deliver.

  In step S <b> 10, the connection control unit 10 of the host unit 1 performs connection control between the client unit 3 and the host unit 1. The connection control unit 10 of the host unit 1 receives a request packet broadcast from the client unit 3 connected in the wireless LAN. The host unit 1 that has received the request packet returns a response packet notifying the IP address of the host unit 1 to the client unit 3 when the connection of the client unit 3 can be accepted.

  The connection control unit 10 of the host unit 1 can also authenticate the user to the connection destination client unit 3. For example, in the case of authentication using a PIN code, after a response packet is transmitted to the client unit 3, an authentication start instruction and a randomly generated PIN code are delivered to the screen control unit 11. The user confirms the PIN code displayed on the screen control unit 11 of the host unit 1 and inputs the PIN code at the screen control unit 31 of the client unit 3. The connection control unit 30 of the client unit 3 transmits the input PIN code to the connection control unit 10 of the host unit 1. The connection control unit 10 of the host unit 1 compares the PIN code generated by the host unit 1 with the received PIN code. If the authentication is successful, a packet indicating approval is returned. If the authentication is unsuccessful, the connection is rejected. Returns the packet indicated. If the authentication fails, a failure notification is further transferred to the screen control unit 11.

  An authentication method for connecting the client unit 3 and the host unit 1 will be described in more detail.

  If there is no other connectable host unit 1 in the wireless LAN, it may be configured to connect without authentication.

  An ID and password for specifying a user may be input to the client unit 3 in advance, and the ID and password may be transmitted to the host unit 1 for authentication.

  The client unit 3 may perform a specified operation in the host unit 1 within an arbitrary time waiting for authentication by the host unit 1. For example, during 20 seconds when the client unit 3 waits for connection authentication, authentication is performed by a method such as pressing the audio mute button twice on the host unit 1 or pressing a button permitting connection on the host unit 1. You may comprise as follows. FIG. 4C is an example of display on the screen control unit 31 of the client unit 3 in the case of such a configuration.

  The MAC address of the client unit 3 and the unique ID of the client unit 3 may be registered in advance in the host unit 1 so that only the registered client unit 3 can be automatically connected.

  The client unit 3 and the host unit 1 may be configured to perform connection by exchanging information such as a connection ID and an IP address using near field communication such as Bluetooth or NFC.

  In step S31, the screen control unit 31 of the client unit 3 controls screen display on the client side. The screen control unit 31 makes it possible to specify whether to enable or disable the voice acquisition unit 32 on the screen of the client unit 3. When invalidity is designated, the screen control unit 31 passes a signal to the voice acquisition unit 32 and stops the voice acquisition unit 32. When valid is designated, a signal is passed to the voice acquisition unit 32, and the voice acquisition unit 32 is activated and maintained.

  FIG. 4A is an example of display on the screen control unit 31 in a state where the voice acquisition unit 32 is disabled. FIG. 4B is an example of display on the screen control unit 31 in a state where the voice acquisition unit 32 is enabled. In either example, it is possible to specify whether the voice acquisition unit 32 is to be enabled or disabled by pressing a button at the bottom of the screen.

  Further, the screen control unit 31 can designate whether to enable or disable the audio playback unit 35 on the screen of the client unit 3. When invalid is designated, the screen control unit 31 passes a signal to the audio reproduction unit 35 and stops the audio reproduction unit 35. When “valid” is designated, a signal is passed to the audio reproduction unit 35, and the audio reproduction unit 35 is activated and maintained.

  Further, the screen control unit 31 inputs the destination IP address of the packet transmission unit 33 on the screen and determines it as the IP address of the host unit 1 as the transmission destination. The input IP address is transferred to the packet transmission unit 30. Alternatively, the screen control unit 31 prepares a start button on the screen for searching for the IP address of the host unit 1 and controls the start operation. When the start button is operated by the user, a start signal is transferred to the connection control unit 30. The PIN code used for connection control is also entered at the same time. The screen control unit 31 passes the input PIN code to the packet transmission unit 33.

  In step S11, the screen control unit 11 of the host unit 1 receives an authentication start instruction and a PIN code from the connection control unit 10, and displays the received PIN code on the screen. Further, the reception port number is input from the user, and the input port number is transferred to the packet reception unit 13.

  In step S12, the voice acquisition unit 12 of the host unit 1 picks up the voice from the microphone M of the host unit 1, and uses the analog-digital (A / D) converter to convert the collected analog signal to the designated sampling frequency. To convert to a digital signal. For example, sound is collected at 16 kHz sampling. The voice as a digital signal is delivered to the echo canceller unit 14.

  In step S32, the voice acquisition unit 32 of the client unit 3 picks up the voice from the microphone M of the client unit 3, and uses the analog / digital (A / D) converter to convert the collected analog signal to the designated sampling frequency. To convert to a digital signal. For example, sound is collected at 16 kHz sampling. The digital audio signal is transferred to the packet transmission unit 33.

  In step S33, the packet transmission unit 33 of the client unit 3 transmits a voice packet with a specified PCM (Pulse Code Modulation) data length using a protocol specified for a fixed port number and IP address. The port number and IP address can also be input by the user at the screen control unit 31. Also, the IP address of the host unit 1 searched by the connection control unit 30 can be received and an IP address can be designated as a transmission destination. The voice packet is transmitted using, for example, RTP (Real-time Transport Protocol) and the PCM data length is set to 20 milliseconds. In addition, the voice packet to be transmitted may be transmitted by a method in which security is ensured by an encryption technique such as IPsec, or may be encoded and transmitted by an encoding technique such as G.711. The voice packet is transmitted to the packet receiving unit 13 of the host unit 1.

  In step S <b> 13, the packet receiving unit 13 of the host unit 1 receives the voice packet sent to the port number input by the user through the screen control unit 10 or a fixed port number. The packet receiver 13 buffers the received voice packet so as to reduce sound interruption. If the voice packet is encrypted, it is decrypted to obtain a PCM signal. If the voice packet is encoded, it is decoded and converted into a digital PCM signal. The PCM signal is transferred to the echo canceller unit 14.

  The packet receiving unit 13 of the host unit 1 has a function of simultaneously processing voice packets sent to a plurality of ports. The received voice packet is subjected to decryption for encryption and voice coding for each port, and a plurality of PCM signals are delivered to the echo canceller unit 14.

  In step S14, the echo canceller unit 14 of the host unit 1 receives the PCM signal from the voice acquisition unit 12 and the PCM signal from another point. The echo canceller 14 aligns the delay with respect to the two input PCM signals. As a method of aligning delay, for example, delay correction using maximum cross-correlation is performed. In addition, the echo canceller unit 14 performs a process of removing the components of the PCM signal from other points from the PCM signal received from the voice acquisition unit 12. For this processing, for example, an echo canceller technique described in “Japanese Patent No. 5087024 (Reference 1)” can be applied. The output result obtained by performing the echo canceller process is transferred to the signal buffer unit 15.

  The echo canceller 14 receives one or more PCM signals from the packet receiver 13 and PCM signals from other points. The echo canceller 14 aligns the delay with respect to one or more PCM signals sent to each port and PCM signals from other points. As a method of aligning delay, for example, delay correction using maximum cross-correlation is performed. In addition, the echo canceller unit 14 performs a process of removing the components of the PCM signal from other points from the PCM signal received at each port of the packet receiving unit 13. This processing is performed by echo canceller processing using a general adaptive filter algorithm (see, for example, “Asada Tadashi,“ Sound Array Signal Processing ”, Corona, 2011 (Reference 2)). Alternatively, the echo canceller technique described in Reference Document 1 may be used. The output result obtained by performing the echo canceller process is transferred to the signal buffer unit 15.

  In step S15, the signal buffer unit 15 of the host unit 1 receives a plurality of PCM signals from the echo canceller unit 14, and aligns the delays of these PCM signals. As a method of aligning delay, for example, delay correction using maximum cross-correlation is performed. A plurality of PCM signals with the same delay are delivered to the microphone array control unit 16.

  In step S <b> 16, the microphone array control unit 16 of the host unit 1 performs microphone array processing for emphasizing specific sound on the plurality of PCM signals received from the signal buffer unit 15 to generate a processed acoustic signal. For example, “Tatsuya Kako, Kazunori Kobayashi, Nakamichi Omuro,“ Proposal of an Amplitude Spectrum Beamformer for Asynchronous Dispersive Microphone Arrays ”, Proc. 1-P-5, 2013 (reference 3) "can be used. Further, as described in Reference Document 2 above, microphone array processing may be performed in which arrival time differences to each PCM signal are aligned and sound in only a specific direction is emphasized. As described in "Removal of residual noise after sound source separation by spectral subtraction", Acoustical Society of Japan Autumn Meeting, 2010 (Ref. 4), noise on the frequency spectrum so that only a specific speaker remains Noise suppression may be performed by performing spectral subtraction by subtracting the spectral components. A plurality of post-processing acoustic signals and speaker section information of voice signals are transferred to the voice service processing unit 17.

  In step S <b> 17, the voice service processing unit 17 of the host unit 1 performs processing according to the provided voice service using the received plurality of processed acoustic signals and speaker section information. The voice service processing unit 17 adjusts the power of voice for each speaker, for example, for use in real-time voice communication. The voice service processing unit 17 also reduces the power of voice for voice to which a speaker is not allocated using the speaker section information. Specifically, the voice service processing unit 17 multiplies the coefficient G. The coefficient G gives a value such as 0.1. Further, the power of each voice is obtained for the voice to which the speaker is allocated, and the coefficient G is multiplied so that the power becomes 1. The voice service processing unit 17 adds the voice signals obtained by multiplication in this way and outputs a processed acoustic signal. Further, a plurality of processed acoustic signals may be transmitted to other points as they are without adding the audio signals.

  In step S18, the speaker array control unit 18 of the host unit 1 performs speaker array processing using the acoustic signal received from the voice service processing unit 17 of the host unit 1 at another point, and generates a processed acoustic signal. For example, by controlling the volume and phase, the directivity of the speaker is increased and area reproduction is realized. In addition, in order to localize the sound source to the left and right, it is possible to adjust the volume of the left and right speakers, so that the speaker is speaking from. The sound field of the entire room space is controlled by the speaker array, and sound field reproduction is possible as if the sound source is sounding from a place where speakers are not present. The processed acoustic signal whose phase and volume are controlled is delivered to the packet transmitter 19. Further, the processed acoustic signal reproduced by the speaker S of the host unit 1 is delivered to the sound reproducing unit 20.

  In step S19, the packet transmission unit 19 of the host unit 1 transmits the voice packet with the specified PCM data length using the protocol specified for the fixed port number and IP address. The port number and IP address can also be input by the user at the screen control unit 11. Further, the IP address of the client unit 3 that has sent the request packet by the connection control unit 10 can be designated. The voice packet is transmitted by RTP, for example, with a PCM data length of 20 milliseconds. The packet to be transmitted may be transmitted by a method that ensures security by an encryption technique such as IPsec, or may be encoded and transmitted by an encoding technique such as G.711. The voice packet is transmitted to the packet receiving unit 34 of the client unit 3.

  In step S <b> 34, the packet receiver 34 of the client unit 3 receives the voice packet sent from the packet transmitter 19 of the host unit 1. The packet receiver 34 buffers the received voice packet to reduce sound interruption. If the voice packet is encrypted, it is decrypted to obtain a PCM signal. If the voice packet is encoded, it is decoded and converted into a digital PCM signal. The PCM signal is delivered to the audio reproduction unit 35.

  In step S <b> 20, the audio reproduction unit 20 of the host unit 1 receives a digital signal of the audio signal from the speaker array control unit 18. This digital signal is, for example, a PCM signal. The PCM signal is converted into an analog signal using a digital / analog (D / A) converter, and reproduction is performed using the speaker S of the host unit 1.

  In step S <b> 35, the audio reproduction unit 35 of the client unit 3 receives the digital signal of the audio signal from the packet reception unit 34. This digital signal is, for example, a PCM signal. The PCM signal is converted into an analog signal using a digital / analog (D / A) converter, and reproduction is performed using the speaker S of the client unit 3.

[Application Example 1]
An application example in which the host unit 1 is implemented as a set-top box and the client unit 3 is implemented as a smartphone in the audio recording and reproducing system of the embodiment will be described.

  A set-top box that becomes the host unit 1 and a smartphone that becomes the client unit 3 are connected in the LAN of the same network. By starting the client unit 3, the request packet is broadcast in the LAN. By requesting a specific packet, the host unit 1 transmits a response packet for notifying its own IP address to the client unit 3. Thereby, the connection between the host unit 1 and the client unit 3 is established.

  By enabling the voice input in the client unit 3, the packetized voice is transmitted from the client unit 3 to the host unit 1. The host unit 1 can pick up the voice of the client unit 3 by processing the voice packet received from the client unit 3.

  In this application example, an audio conference system can be realized by using a plurality of smartphones. One smartphone arbitrarily selected from a plurality of smartphones is set as the host unit 1, and the remaining plurality of smartphones are set as the client unit 3. By connecting a plurality of client units 3 to one host unit 1, it is possible to emphasize a voice for each speaker who talks near each smartphone and obtain a sound collection signal.

  In this application example, a speaker array can be realized by using a plurality of smartphones. One smartphone arbitrarily selected from a plurality of smartphones is set as the host unit 1, and the remaining plurality of smartphones are set as the client unit 3. The host unit 1 controls the phase and playback timing of the input acoustic signal, and transmits it to each of the plurality of client units 3. By reproducing the acoustic signal received by the client unit 3 with the speaker S, it is possible to realize area reproduction in which sound is reproduced only in a specific direction. In addition, sound field reproduction that reproduces the sound field of the entire space by reproducing different sounds in each direction or creating a sound source in a place where there is no speaker is possible.

[Application Example 2]
An application example in which the host unit 1 is implemented as a set-top box, the client unit 3 is implemented as a smartphone, and the number of connected client units 3 is changed in the audio recording and reproducing system of the embodiment will be described.

  A set-top box that becomes the host unit 1 and a smartphone that becomes the client unit 3 are connected in the LAN of the same network. By starting the client unit 3, the request packet is broadcast in the LAN. By receiving the request packet, the host unit 1 transmits a response packet for notifying its own IP address to the client unit 3. Thereby, the connection between the host unit 1 and the client unit 3 is established.

  By enabling the voice input in the client unit 3, the packetized voice is transmitted from the client unit 3 to the host unit 1. The host unit 1 can pick up the voice of the client unit 3 by processing the voice packet received from the client unit 3.

  Further, when the number of client units 3 is increased, the client unit 3 is connected in the same LAN and connected to the host unit 1 in the same manner. At this time, the connection control unit 10 of the host unit 1 may permit a plurality of connections, and if it is desired to limit the number of simultaneous connections, a process of rejecting the connection of the client unit 3 that has been connected later is performed. Alternatively, the connection of the client unit 3 connected first may be rejected and the connection of the client unit 3 connected later may be permitted.

  When a new client is connected by the connection control unit 10, the microphone array control unit 16 resets internal information and performs learning of the filter again. Further, when a new client unit 3 is connected by the connection control unit 10, the speaker array control unit 18 resets internal information and performs filter learning again.

[Application Example 3]
It is also possible to acquire a fee by selling an application that implements the client unit 3. An application that implements the client unit 3 may be added as an optional function of the existing voice call software. At this time, the application may be acquired for the first time by paying an optional fee. Moreover, you may make it collect a usage fee according to the time which talked using the application. You may make it arrange | position an advertisement in an application and obtain an income by advertising revenue. The application itself may be distributed free of charge, and the fee may be acquired by a method of charging when connected to the host unit 1.

[Effect of the invention]
Acoustic signals obtained from a plurality of freely arranged acoustic devices differ in sampling frequency and microphone sensitivity. The present invention makes it possible to easily increase the number of microphones as necessary by using asynchronous speech processing that can emphasize the sound of a specific speaker even if different acoustic signals are used. This technology realizes speech enhancement and noise suppression.

  The voice collecting and reproducing system according to the present invention easily realizes an extended microphone function by collecting acoustic signals from a plurality of terminals into one host unit. This makes it possible to perform microphone array processing such as emphasizing or suppressing noise of a specific speaker and not collecting the voice of a specific speaker by using a plurality of microphones simultaneously compared to a single conventional microphone. It becomes like this.

  Moreover, the audio | voice sound collection reproduction | regeneration system of this invention easily implement | achieves an extended speaker function by transmitting the acoustic signal from one host part toward several client parts. As a result, a conventional speaker array system can be realized with a wireless network, and area playback where sound can be heard only in a specific area, and sound field playback that reproduces the sound field of the space by controlling the signals of multiple speakers can be performed. Can do.

  The present invention is not limited to the above-described embodiment, and it goes without saying that modifications can be made as appropriate without departing from the spirit of the present invention. The various processes described in the above embodiment may be executed not only in time series according to the order of description, but also in parallel or individually as required by the processing capability of the apparatus that executes the processes or as necessary.

[Program, recording medium]
When various processing functions in each device described in the above embodiment are realized by a computer, the processing contents of the functions that each device should have are described by a program. Then, by executing this program on a computer, various processing functions in each of the above devices are realized on the computer.

  The program describing the processing contents can be recorded on a computer-readable recording medium. As the computer-readable recording medium, for example, any recording medium such as a magnetic recording device, an optical disk, a magneto-optical recording medium, and a semiconductor memory may be used.

  The program is distributed by selling, transferring, or lending a portable recording medium such as a DVD or CD-ROM in which the program is recorded. Furthermore, the program may be distributed by storing the program in a storage device of the server computer and transferring the program from the server computer to another computer via a network.

  A computer that executes such a program first stores, for example, a program recorded on a portable recording medium or a program transferred from a server computer in its own storage device. When executing the process, the computer reads a program stored in its own recording medium and executes a process according to the read program. As another execution form of the program, the computer may directly read the program from a portable recording medium and execute processing according to the program, and the program is transferred from the server computer to the computer. Each time, the processing according to the received program may be executed sequentially. Also, the program is not transferred from the server computer to the computer, and the above-described processing is executed by a so-called ASP (Application Service Provider) type service that realizes the processing function only by the execution instruction and result acquisition. It is good. Note that the program in this embodiment includes information that is used for processing by an electronic computer and that conforms to the program (data that is not a direct command to the computer but has a property that defines the processing of the computer).

  In this embodiment, the present apparatus is configured by executing a predetermined program on a computer. However, at least a part of these processing contents may be realized by hardware.

DESCRIPTION OF SYMBOLS 1 Host part 3 Client part 5 Audio | voice sound collection reproduction | regeneration system 9 Communication network 10, 30 Connection control part 11, 31 Screen control part 12, 32 Audio | voice acquisition part 13, 34 Packet receiving part 14 Echo canceller part 15 Signal buffer part 16 Microphone array Control unit 17 Audio service processing unit 18 Speaker array control unit 19, 33 Packet transmission unit 20, 35 Audio reproduction unit

Claims (10)

A sound collection system including a host unit and at least one client unit,
The client part
An audio acquisition unit that transmits an acoustic signal generated based on the collected audio to the host unit;
A connection control unit that transmits a connection request to the host unit;
Including
The host part
A sound acquisition unit that generates an acoustic signal based on the collected sound;
A microphone array control unit that outputs a processed acoustic signal obtained by performing a desired microphone array process using an acoustic signal output from the audio acquisition unit of the host unit and an acoustic signal received from the client unit;
A connection control unit that receives the connection request and adds the client unit to the microphone array control unit;
Including voice recording system. The sound collection system according to claim 1,
The voice collecting and reproducing system further includes a communication network configured by wireless communication,
The host unit and the client unit can be connected to each other via the communication network,
The connection control unit of the client unit transmits the connection request when the communication network is available. The voice pickup system according to claim 1 or 2,
The microphone array control unit emphasizes a specific sound included in an acoustic signal output from the sound acquisition unit of the host unit and an acoustic signal received from the client unit, and / or suppresses a sound other than the specific sound. A sound collection system that performs the above-described microphone array processing using a filter. The sound collection system according to claim 3,
The microphone array control unit resets the filter and learns again when the client unit is added by the connection control unit of the host unit. The voice sound collection system according to any one of claims 1 to 4,
Upon receiving the connection request, the connection control unit of the host unit authenticates the client unit, and adds the client unit to the microphone array control unit only when the authentication is successful. system. An audio playback system including a host unit and at least one client unit,
The client part
A connection control unit that transmits a connection request to the host unit;
An audio reproduction unit for reproducing the processed acoustic signal received from the host unit;
Including
The host part
A speaker array controller that outputs the processed acoustic signal obtained by performing desired speaker array processing on the input acoustic signal, and transmits the acoustic signal to the client unit;
An audio reproduction unit for reproducing the processed acoustic signal;
A connection control unit that receives the connection request and adds the client unit to the speaker array control unit;
Including audio playback system. The audio reproduction system according to claim 6,
The audio reproduction system further includes a communication network configured by wireless communication,
The host unit and the client unit can be connected to each other via the communication network,
The audio playback system, wherein the connection control unit of the client unit transmits the connection request when the communication network is available. The voice reproduction system according to claim 6 or 7,
The speaker array control unit performs the speaker array processing using a filter that emphasizes a specific sound included in the input acoustic signal and / or suppresses a sound other than the specific sound. Audio playback system. The voice reproduction system according to claim 8, wherein
The microphone array control unit resets the filter and learns again when the client unit is added by the connection control unit of the host unit. The sound reproduction system according to any one of claims 6 to 9,
The connection control unit of the host unit authenticates the client unit when receiving the connection request, and adds the client unit to the speaker array control unit only when the authentication is successful. .