JP4929673B2 - Audio conferencing equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a voice conference apparatus which allows a user to easily change a sound source position, does not prepare the number of speakers according to the number of counterparts, and also allows the user to easily identify which person talks out of a plurality of counterparts. <P>SOLUTION: The voice conference apparatus 200 is provided with: an input unit 21 which inputs each voice signal from a plurality of the counterparts; and a delay unit 24, an adding unit 25, a D/A converter 26, and amplifiers 27 wherein a speaker array 20 with a plurality of speaker units SP arranged in a line and directed downward are connected, and independent delay control for each voice signal input from the input unit 21 is performed so that voice beams of each voice signal focus at different point voice sources, then inputs the signal to the speaker array 20. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention relates to an audio conference apparatus that performs an audio conference with a plurality of other parties by communicating with the audio conference apparatuses of a plurality of other parties.

2. Description of the Related Art Conventionally, an audio conference apparatus for performing a conference through a telephone conference or the like with a plurality of other parties at different points is widely known. Such an audio conference apparatus includes a speaker and a microphone (hereinafter referred to as “microphone”). The voice conference apparatus transmits the voice of the conference attendee collected by the microphone to the voice conference apparatus of the other party, and emits the voice of the other party received from the voice conference apparatus of the other party from the speaker. (See, for example, Patent Document 1). As a result, a call can be made with the other party in the remote place, and the conference attendee can have a voice conference with the other party in the remote place.
JP-A-5-158492

  In a conventional audio conference apparatus, a plurality of opponent's voices are emitted using a single non-directional speaker (with a wide directivity range). For this reason, since the voices of a plurality of opponents are emitted from the same sound source, it is difficult for the user to identify which one of the plurality of opponents is speaking.

  In order to solve this problem, a method of preparing a plurality of speakers and emitting sounds from a plurality of opponents from different speakers can be considered. However, in this method, the same number of speakers as the number of opponents must be prepared in advance. Also, when changing the sound source position, the user must change the position of the speaker each time, which is troublesome.

  In order to solve the above-described problems, the present invention reduces the effort given to the user for changing the sound source position, and the user can select any one of a plurality of opponents without preparing the number of speakers according to the number of opponents. It is an object of the present invention to provide an audio conference apparatus that can easily identify who is talking.

  In order to solve the above problems, the present invention employs the following means.

The present invention connects an input unit that inputs the audio signals from multiple sources along with the transmission source identification information, the speaker array having a plurality of speaker units and arranged downwardly in a line, the entering force A sound emitting unit that performs independent delay control on each sound signal input by the unit and inputs the sound signal to the speaker array, and the sound emitting unit determines a position pattern of a virtual point sound source of each sound signal. Based on the source identification information selected and input together with each audio signal from the input unit, and the selected position pattern, the audio beam of each audio signal is virtual at different positions in the longitudinal direction of the speaker array. An audio conference apparatus that performs control so as to focus on a point sound source .

  According to the above configuration, each audio signal from a plurality of opponents is input to the input unit. The input sound signal is controlled by the sound emitting unit so that the sound beams of the sound signals from the voice conference apparatuses of the other party are focused by different virtual point sound sources, and input to the speaker array. As a result, the voices from a plurality of opponents are localized at different positions, and the user can easily identify which party is listening to the voices.

  Since the speaker array is used to localize the virtual point sound source as described above, the position of the virtual point sound source and the number of virtual point sound sources can be changed as needed. As a result, as described above, the user can listen to the sound from any other party without the need to provide the user with the number of speakers according to the number of the other party and less effort to change the sound source position to the user. It is possible to identify whether or not

  In the speaker array, since the sound emission side of the speaker unit row is positioned below, the sound beam is output downward from the speaker unit row. Then, an audio beam reflected by an obstacle below the speaker array (for example, a desk or a floor when the apparatus is on a desk) propagates obliquely upward of the obstacle.

  As a result, it is possible to output an audio beam having the same content in two directions orthogonal to the line direction of the speaker unit. For this reason, when there are a plurality of users, it is possible to listen to the sound divided into these two directions.

  In addition, it is possible to prevent sound leakage for a person who is behind a specific listener (assuming that this listener is facing the direction of arrival of the sound beam). Further, even though the speaker array can control the directivity of the sound beam, some sound leaks in the direction orthogonal to the sound emitting surface. In the present invention, since a sound beam is output downward from the speaker array, it is possible to effectively prevent a person other than a specific listener from listening to the sound due to the sound leakage.

  According to the present invention, sound from a plurality of opponents is localized to different virtual point sound sources using the speaker array. For this reason, the position of the virtual point sound source and the number of virtual point sound sources can be easily changed to arbitrary positions. As a result, it is easy for the user to listen to the sound from the other party without preparing the number of speakers according to the number of the other party and less effort for the user to change the sound source position. Can be identified.

  Moreover, it installs so that the sound emission side of the speaker unit row may face downward. For this reason, an audio beam is output downward from the speaker unit row and is reflected by an obstacle below the speaker array (for example, a desk or a floor surface when the apparatus is on a desk). Propagates diagonally above the obstacle.

  As a result, an audio beam having the same content can be output in two directions orthogonal to the line direction of the speaker unit. For this reason, when there are a plurality of users, it is possible to listen to the sound divided into these two directions. Moreover, it is possible to effectively prevent a person other than the specific listener from listening to the sound.

  With reference to FIGS. 1-8, the audio conference system 100 which is embodiment of this invention is demonstrated in detail. FIG. 1 is a diagram schematically showing an audio conference system 100. The audio conference system 100 is a system for conducting an audio conference among a plurality of conference attendees h at a plurality of conference points. The audio conference system 100 is a system in which a plurality of audio conference apparatuses 200 arranged at each conference point are connected to a network N. This network is, for example, a wide area network such as the Internet or a LAN.

  Each voice conference apparatus 200 has a function of communicating with another (the other party) voice conference apparatus 200 (the other party apparatus 200 ′) connected to the network N, and transmits and receives a conference audio signal by this communication. The communication protocol used for this communication is not particularly limited, and for example, TCP (Transmission Control Protocol) / IP (Internet Protocol) or the like is used.

  FIG. 2 is a perspective view of the audio conference apparatus 200 shown in FIG. The audio conference apparatus 200 has a long, substantially rectangular parallelepiped shape, and a speaker apparatus that has a long, substantially rectangular parallelepiped shape on the upper portion of the frame body 1 that has a rectangular shape with open sides in the YY direction in the figure. 2 is provided. A microphone 3 is connected to the speaker device 2 via a connection line 3a. A speaker array 20 is arranged on the lower surface of the speaker device 2 so that the sound emission side faces downward.

  When the conference audio transmitted from the counterpart device 200 ′ is input to the speaker array 20, the conference audio is emitted. Further, the voice of the conference attendee h, who is the user, is collected by the microphone 3, and the collected voice is transmitted to the partner apparatus 200 ′ and emitted from the speaker array 20 of the partner apparatus 200 ′. Thereby, a voice conference can be performed between the plurality of voice conference apparatuses 200.

  The speaker array 20 includes eight speaker units SP (SP1 to SP8) arranged in a line downward in the longitudinal direction. When an audio signal is input to the speaker units SP1 to SP8, an audio beam is output from the speaker array 20 so as to be directed downward.

  The sound beam output downward is reflected by the lower surface 10 (hereinafter referred to as the reflector 10) of the frame 1 and is obliquely upward, and is emitted from the side of the frame 1 in the YY direction in the figure. . In addition, the reflecting plate 10 is made of, for example, resin and is formed into a flat plate, and thereby, the sound beam can be favorably reflected. As long as the sound beam can be reflected appropriately, the material of the reflector 10 is not limited to resin, and may be a metal material or the like. Moreover, the shape of the reflecting plate 10 is not limited to a flat plate, and may be a gently curved shape or the like.

  Then, by controlling the input timing of the audio signal to the speaker units SP1 to SP8, the audio beam can be focused on the virtual point sound source P, and the position of the virtual point sound source P can be changed to an arbitrary position. it can. That is, the sound signal can be localized on the virtual point sound source P by adding a delay time as indicated by an arrow in the drawing to the sound signals input to the speaker units SP1 to SP8. As a result, the conference attendee h can be recognized so that the conference audio can be heard from the virtual point sound source P.

  FIG. 3 is a diagram for explaining the installation method of the audio conference apparatus 200 and the directivity control of the audio beam shown in FIG. The room R is not a conference room dedicated to audio conferencing but a normal office room. FIG. 3 is a view of the room R as viewed from the side. FIG. 4 is a view of the room R shown in FIG. 3 as viewed from the Y direction. In FIG. 4, for the sake of easy understanding of the drawing, the conference attendee h2 and the conference chair on which the conference attendee h2 is seated are omitted.

  In the room R, two meeting attendees h (h1, h2) are seated so as to face each other across the conference desk. On the conference desk, the audio conference apparatus 200 is arranged such that the YY direction (see FIG. 1) is in the direction in which the conference attendee h1 and the conference attendee h2 face each other. As shown in FIG. 3, an audio beam is output from the audio conference apparatus 200 in the downward direction. The audio beam is reflected by the reflector 10, and is divided into two directions in the YY direction and propagates obliquely upward. . That is, the sound beam propagates diagonally upward to the conference attendee h1 and the conference attendee h2.

  For this reason, compared with outputting an audio beam in the horizontal direction to the conference attendees h1 and h2, it is possible to effectively prevent a person located behind the conference attendees h1 and h2 from listening to the audio. be able to. At the same time, since the directivity of the sound beam can be controlled behind XX in FIG. 2, sound leakage in the XX direction can be effectively prevented.

  Further, even though the speaker device 2 can control the directivity of the sound beam, some sound leaks in a direction orthogonal to the sound emitting surface. In this embodiment, since an audio beam is output downward from the speaker array 20, it is possible to prevent a person other than a specific listener from listening to the sound due to the sound leakage.

  Then, as shown in FIG. 4, this sound beam is controlled so that sounds from a plurality of counterpart terminals 200 'are focused on different virtual point sound sources P in the line direction (XX direction) of the speaker unit SP. The For example, when a voice conference between four points is performed, the voice beam is controlled so that sound images are localized by three different virtual point sound sources P (P1 to P3). For this reason, the conference attendee h1 is the position of the virtual point sound source P in the XX direction, and the position on the Y side from the virtual point sound source P by the distance from the virtual point sound source P to the reflector 10 in the Y-Y direction. Recognize that there is a sound source. Also, the conference attendee h2 is the position of the virtual point sound source P in the XX direction, and the position on the −Y side from the virtual point sound source P by the distance from the virtual point sound source P to the reflector 10 in the YY direction. Recognize that there is a sound source.

  As a result, the conference attendees h1 and h2 can recognize the voices from the plurality of counterpart devices 200 'so that they can be heard from different sound sources, respectively, and it is relatively easy to identify which party is listening to the voice. Can be made.

  In addition, the audio conference apparatus 200 recognizes the conference attendee h so that the audio can be heard from the sound sources at a plurality of locations by focusing the sound beams from the speaker array 20 at the plurality of virtual point sound sources P as described above. Let For this reason, the position of the virtual point sound source P can be easily changed by changing the delay time given to the audio signal input to the speaker unit SP. At the same time, it is possible to change the number of virtual point sound sources P only by preparing the number of channels of the functional unit to which the delay time is provided by the number of desired virtual point sound sources P.

  Further, as described above, since the sound beam is reflected by the reflecting plate 10 and divided and output in two directions in the YY direction, the sound components in the two separated directions have the same contents. For this reason, when listening to audio components in two directions, the conference attendee h recognizes each sound image so that the sound image is localized at the opposite positions. That is, when the audio from the conference attendee h1 and the conference attendee device 200 'in Hokkaido is localized at the virtual point sound source P1, the conference attendee h1 has the sound source of the audio at his right end. The conference attendee h2 is made to listen as if there is a sound source of this sound at his left end. Thus, both the conference attendees h1 and h2 can recognize the sounds from the plurality of counterpart devices 200 ′ so that they can be heard from different sound sources.

  FIG. 5 is a block diagram schematically showing the configuration of the audio conference apparatus 200 shown in FIG. In addition to the speaker array 20, the speaker device 2 includes an input / output interface 21, an echo canceller 22, a signal distribution unit 23, a delay unit 24, an addition unit 25, a D / A (digital / analog) converter 26, an amplifier 27, An operation unit 28 and a control unit 29 are provided.

  The input / output interface 21 corresponds to the input unit of the present invention, is connected to the network N via a communication cable (not shown) connected to the connection terminal 30, and the audio conference apparatus 200 'connected to the network N. Send and receive digital audio signals to and from. The echo canceller 22 receives a conference audio signal (received audio signal) received from the audio conference apparatus 200 ′ via the input / output interface 21. This received audio signal is input in packet units in this embodiment. Communication between the audio conference apparatuses 200 is not limited to packet communication, and the received audio signal may not be input in units of packets.

  The echo canceller 22 uses this input signal to generate a pseudo signal that simulates an echo component output from the speaker array 20 and fed back to the microphone 3. The echo canceller 22 inputs the received audio signal to the signal distribution unit 23 via the input / output interface 21. The echo canceller 22 removes an echo component by removing a pseudo signal from an audio signal (described later) input from the microphone 3.

  The signal distribution unit 23 is realized by, for example, a DSP (Digital Signal Processor) or the like, and refers to the transmission source ID included in the input received audio signal, and inputs it to the channel of the delay unit 24 corresponding to the transmission source ID. Processing (distribution processing) is executed. This distribution process will be described later in detail with reference to FIG. The transmission source ID is, for example, an IP address or the like, and is transmitted by being included in communication data when a plurality of voice conference apparatuses 200 communicate with each other. In the signal distribution unit 23, a transmission source ID and a channel of the delay unit 24 corresponding to the transmission source ID are set in association with each other. Based on this setting, the signal distribution unit 23 distributes and inputs the received audio signal to each channel of the delay unit 24.

  The delay unit 24 corresponds to the sound emitting unit of the present invention, and is provided with a plurality of channels (n channels). When distinguishing these n channels, the channel numbers are attached as subscripts and are described as delay units 241 to 24n. The same number (eight) of delay units 241 to 24n and speaker units SP1 to SP8 of the plurality of channels are provided. Hereinafter, when distinguishing each delay part 24, the same number as the corresponding thing among the speaker units SP1-SP8 is attached as a subscript. For example, the delay unit 24 corresponding to the speaker unit SP1 is referred to as a delay unit 24-1. By setting each delay unit 24-1-24-8 to the same delay time (for example, the delay time as shown in FIG. 2) until the sound from the virtual point sound source P reaches each speaker unit SP. The sound image can be localized on the virtual point sound source P.

  The delay units 241 to 24n of each channel correspond to the positions of the virtual point sound sources P that are different in the XX direction. That is, each channel is set with a delay time for focusing the sound beam with a different virtual point sound source P, and the set delay time is given to the input signal. Further, each channel is associated with a different transmission source, and the reception voice signal of the corresponding transmission source is input from the signal distribution unit 23 as described above. As a result, the received audio signals from different transmission sources are given a delay time for sound image localization to different virtual point sound sources P. For this reason, it is possible to focus the sound received from different counterpart device 200 ′ on different virtual point sound sources P.

  The delay units 24-1 to 24-8 of the respective channels input the audio signals provided with the delay time to the corresponding adding units 25, respectively. The adding units 25 correspond to the sound emitting units of the present invention and are provided by the number of delay units 24-1 to 24-8. In addition, when identifying these addition parts 25, the same subscript as the corresponding delay parts 24-1 to 24-n is attached. Each of these adders 25-1 to 25-8 inputs the received audio signal to which the delay time is given from the corresponding delay unit 24. Each adder 25 synthesizes the input audio signals from the respective channels and inputs them to the corresponding D / A converter 26.

  The D / A converter 26 corresponds to the sound emitting unit of the present invention, and is provided in the number of the adding units 25-1 to 25-8. In addition, when identifying these D / A converters 26, the same subscripts as the corresponding adding units 25-1 to 25-8 are attached. Each of the D / A converters 26-1 to 26-8 receives a received audio signal to which a delay time is added from the corresponding adder 25. The D / A converters 26-1 to 26-8 convert the received digital received audio signal into analog and input it to the corresponding amplifier 27.

  The amplifier 27 corresponds to the sound emission unit of the present invention and amplifies the signal level of the input audio signal. The amplifier 27 is provided in the number corresponding to the speaker units SP1 to SP8. Hereinafter, when distinguishing each amplifier 27, the same number as the corresponding one among the speaker units SP1 to SP8 is attached as a subscript.

  The amplifiers 27-1 to 27-8 receive received audio signals from the adders 25-1 to 25-8 via the D / A converter 26 (26-1 to 26-8). The amplifiers 27-1 to 27-8 amplify the signal level of the input reception audio signal and input the amplified signal levels to the corresponding speaker units SP1 to SP8. As a result, the voice of the received voice signal is emitted from the speaker units SP1 to SP8, and the voice of the other party from the voice conference apparatus 200 ′ is emitted.

  The operation unit 28 receives an operation of a user such as a conference attendee h or an operator, and inputs an operation signal indicating the operation content to the control unit 29. This user operation includes an operation for starting an audio conference and an operation for presetting the audio conference.

  The operation for the presetting includes, for example, an operation for selecting a conference point. The operation of selecting a conference point is an operation of selecting which of the audio conference apparatuses 200 arranged at a plurality of points constituting the audio conference system 100 to perform an audio conference with.

  For example, it is assumed that the audio conference apparatuses 200 are arranged in “Hokkaido”, “Tokyo”, “Nagoya”, and “Osaka”, respectively, and the audio conference apparatus 200 is arranged in Osaka. Here, when an audio conference is to be held between “Tokyo” and “Nagoya” among “Hokkaido”, “Tokyo”, and “Nagoya”, the user enters the numbers indicating “Tokyo” and “Nagoya” on the operation section. The number is input using a numeric keypad 28 not shown. As a result, it is input that the conference points are “Tokyo” and “Nagoya”.

  Further, in the audio conference apparatus 200, the audio from the partner apparatus 200 'at the selected conference point is localized at a plurality of different point sound source positions as described above. For the preset operation, a virtual point sound source is used. There is an operation of selecting a position pattern of P. Hereinafter, the position pattern of the virtual point sound source P will be described.

  FIG. 6 is a diagram illustrating the position of the virtual point sound source P viewed from above. (A) shows the state where the sound from the counterpart device 200 'at the three points is localized to the virtual point sound source P separated by an equal distance when the conference between the four points is performed. (B) shows a state in which, when a conference between three points is performed, the sound from the counterpart device 200 ′ at two points is localized to the virtual point sound source P separated by an equal distance.

  (C) is a case where a meeting between three points is performed, and when the other party using the one-party device 200 'is the chairperson, the voice from the chairperson is sent to the other-party device 200' at the other two points. Is positioned away from the virtual point sound source P. As a result, the conference attendee h can be made to clearly recognize which counterpart device 200 'is the voice of the chairperson.

  In this way, the virtual point sound sources P of the voices from the counterpart devices 200 'are evenly arranged as shown in FIGS. 10A and 10B, or the chairperson is set as shown in FIG. The position pattern of the virtual point sound source P, such as whether or not to arrange, is set based on the user's selection. Further, when setting the chairperson, the user performs an operation of selecting a conference district to be the chairperson.

  As described above, when the selection of the position pattern of the conference district and the virtual point sound source P is received by the operation unit 28, the process of associating the conference point selected by the control unit 29 with the position of the virtual point sound source P (corresponding Attachment process) is performed (details will be described later).

  The control unit 29 includes a storage unit such as a CPU (Central Processing Unit) and a memory, for example. By executing the program stored in the memory, the control unit 29 controls the operation of each unit of the speaker device 2, such as a call with the audio conference apparatus 200 ′.

  In addition, the control unit 29 executes processing for performing the audio conference prior setting for each channel of the delay unit 24 and the signal distribution unit 23. Specifically, the control unit 29 inputs an operation signal indicating selection of a conference area and an operation signal indicating selection of the position pattern of the virtual point sound source P from the operation unit 28. Using these input signals, the control unit 29 performs association processing described later with reference to FIG. By executing this association process, the control unit 29 associates the transmission source ID of the selected conference point with the position of the virtual point sound source P.

  At the same time, the control unit 29 associates the transmission source ID of the selected conference point with the channel of the delay unit 24 and sets this association in the signal distribution unit 23. With this setting, as described above, the signal distribution unit 23 refers to the transmission source ID of the received reception audio signal and inputs the audio signal to the channel corresponding to the transmission source ID. In addition, the control unit 29 calculates a delay time for focusing the sound beam at the position of the virtual point sound source P for each conference point, and sets it to the channel corresponding to the delay unit 24.

  With this setting, the received audio signal input to the channel corresponding to the delay unit 24 is given a delay time corresponding to the conference point, and a sound image is generated at the position of the virtual point sound source P corresponding to each conference point. It will be localized.

  The audio conference apparatus 200 includes a microphone amplifier 31 and an A / D converter 32 in addition to the above configuration. The microphone amplifier 31 inputs a conference audio signal (transmission audio signal) from the microphone 3 connected to the connection terminal 33. The microphone amplifier 31 amplifies the input transmission audio signal and inputs it to the A / D converter 32. The A / D converter 32 converts the input analog transmission voice signal into a digital signal and inputs it to the echo canceller 22.

  The echo canceller 22 removes the echo component by removing the pseudo signal from the input transmission voice signal as described above. Then, the transmission audio signal is transmitted to the audio conference apparatus 200 ′ via the echo canceller 22 -input / output interface 21 -network N. When the transmission audio signal is transmitted from the input / output interface 21, the transmission source ID of the audio conference apparatus 200 is included and transmitted.

  FIG. 7 is a flowchart showing processing executed by the audio conference apparatus 200 shown in FIG. 6, wherein (a) is a flowchart showing association processing, and (b) is a flowchart showing sorting processing.

  Referring to (a), first, the control unit 29 receives an operation signal indicating the selection of a conference point (S1), and thereafter receives an operation signal indicating the position pattern of the virtual point sound source P (S2). ).

  The control unit 29 acquires the virtual point sound source P and associates the transmission source ID of the selected conference point with the acquired virtual point sound source P (S3). This association will be specifically described below. The control unit 29 stores a table T1 (see FIG. 8A) for registering the number of conference points and the position of the virtual point sound source P associated with the position pattern of the virtual point sound source P. Then, the control unit 29 refers to the table T1 with the number of conference points and the position pattern of the virtual point sound source P, and acquires the position of the virtual point sound source P corresponding to the number of conference points and the position pattern of the virtual point sound source P. .

  In addition, the control unit 29 stores a table T2 (see FIG. 8B) in which the conference point and the transmission source ID of the counterpart device 200 ′ at the conference point are registered. The control unit 29 refers to the table T2 at the selected conference point, and acquires the transmission source ID corresponding to this conference point. The control unit 29 stores this association by randomly associating the acquired transmission source ID with the position of the acquired virtual point sound source P.

  Next, the control unit 29 associates each transmission source ID with the channel of the delay unit 24, and sets the association between the channel of the delay unit 24 and the transmission source ID in the signal distribution unit 23 (S4). Then, the control unit 29 calculates a delay time for focusing the sound beam with the acquired virtual point sound source P for each virtual point sound source P (S5) and sets it to the channel of the corresponding delay unit 24 (S6). ). Thereafter, the control unit 29 ends this process.

  In this flowchart, step S2 and step S3 are executed, but instead of this, the control unit 29 uses a table in which the conference point and the position of the virtual point sound source P corresponding to this conference point are registered instead of the table T1. The configuration may be such that the position of the virtual point sound source P corresponding to the conference point is acquired using this table, and the position of the virtual point sound source P corresponding to the transmission source ID of the conference point is thereby acquired.

  Next, a distribution process executed by the signal distribution unit 23 will be described with reference to FIG. First, the signal distribution unit 23 repeatedly determines and waits at predetermined time intervals until it determines that the received audio signal has been input or not (S11). When it is determined that the received voice signal has been input (YES in S11), the signal distribution unit 23 refers to the transmission source ID included in the received voice signal. The signal distribution unit 23 determines the channel of the delay unit 24 corresponding to the referenced transmission source ID based on the association between the set transmission source ID and the channel of the delay unit 24 (S12).

  Thereafter, the signal distribution unit 23 inputs the received audio signal to the determined channel (S13). Thereafter, the signal distribution unit 23 returns the process to step S11.

  As described above, in the present embodiment, a delay time is given such that the received voice signal transmitted from the counterpart device 200 ′ arranged at a different conference point is focused at the position of the different virtual point sound source P. Is done. As a result, a sound beam can be output from the speaker array 20 so that sound from different counterpart devices 200 ′ is localized at different virtual point sound sources P. For this reason, it is possible to easily identify the conference participant h who is listening to the sound from which conference point.

  In the present embodiment, the speaker array 20 is arranged so that the sound emission sides of the speaker units SP1 to SP8 are positioned below. At the same time, the reflector 10 is disposed below the speaker array 20. As a result, the sound beam output downward from the speaker array 20 and reflected by the reflector 10 is divided into two directions in the XX direction, obliquely upward, and output from the side of the frame 1.

  As a result, it is possible to output in two directions a sound beam that allows sound from different counterpart devices 200 ′ to be localized at different virtual point sound sources P. For this reason, as shown in FIG. 3, the sound image localization is performed at the positions of the different virtual point sound sources P with respect to the voices from the different counterpart devices 200 'for both the conference attendees h1 and h2 seated facing the conference desk. Can be made. Further, when a horizontal audio beam is output to the conference attendees h1 and h2, sound leakage to a person in the output direction of the audio beam tends to occur. In the present embodiment, an audio beam is output so as to go diagonally upward from below with respect to meeting attendees h1 and h2. For this reason, it is possible to effectively prevent such sound leakage to the surroundings of the conference attendees h1 and h2.

  Further, even though the speaker array 20 can control the directivity of the sound beam, some sound leaks in the direction orthogonal to the sound emitting surface. In the present embodiment, since a sound beam is output downward from the speaker array 20 and directivity control is performed in the direction of the listener by the reflector 10, this sound leakage causes a person other than the specific listener to listen to the sound. Can be prevented.

  The present embodiment can employ the following modified examples.

  (1) In the present embodiment, the audio conference apparatus 200 includes the reflector 10, but is not limited thereto. For example, the frame 1 may have a configuration in which an audio beam is reflected on a conference desk or a floor surface on which the audio conference apparatus 200 is installed without including the reflector 10 (lower surface).

  (2) In this embodiment, the number of speaker units SP is 8. However, the number of speaker units SP is not limited to this number. If the number of speaker units SP that can control the directivity and beam width of the sound beam is at least provided. Good.

FIG. 1 is a diagram schematically showing an audio conference system. It is the perspective view which carried out the cross sectional view of the audio conference apparatus shown in FIG. It is a figure for demonstrating the installation method of the audio conference apparatus shown in FIG. 2, and directivity control of an audio beam. It is the figure which looked at the room R shown in FIG. 3 from the Y direction. It is a block diagram which shows roughly the structure of the audio conference apparatus shown in FIG. It is a figure which shows the position of a virtual point sound source. (A) shows a state in which when a conference between four locations is performed, the sound from the counterpart device at the three locations is localized to a virtual point sound source separated by an equal distance. (B) shows a state in which, when a conference between three points is performed, the sound from the counterpart device at two points is localized to a virtual point sound source separated by an equal distance. FIG. 7 is a flowchart showing processing executed by the voice conference apparatus shown in FIG. 6, wherein (a) is a flowchart showing association processing, and (b) is a flowchart showing sorting processing. It is a figure which shows the table which a control part memorize | stores.

Explanation of symbols

200-voice conference device 3-microphone 20-speaker array 21-input / output interface (input unit) 24-delay unit (sound emitting unit) 25-adder unit (sound emitting unit) 26-D / A converter 27-amplifier unit ( 29-Control part P-Virtual point sound source SP-Speaker unit

Claims (2)

An input unit for inputting each audio signal from a plurality of transmission sources together with transmission source identification information ;
A speaker array comprising a plurality of speaker units arranged in a line and downwards is connected, and the sound emission input to the speaker array is performed by performing independent delay control on each audio signal input at the input unit. And
With
The sound emitting unit selects a position pattern of a virtual point sound source of each audio signal,
Based on the transmission source identification information input together with each audio signal from the input unit and the selected position pattern, the audio beam of each audio signal is a virtual point sound source at a different position in the longitudinal direction of the speaker array. An audio conference apparatus that performs control so as to focus. The audio conference apparatus according to claim 1, wherein the sound emitting unit sets the position of the virtual point sound source above the speaker array.

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