JP2787610B2 - Audio conference equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] With regard to a voice conference device, an object of the present invention is to provide a voice conference device that facilitates discrimination of each speaker at the time of simultaneous speech, and to provide voice signals from three or more conference participants. An audio conferencing device for transmitting and receiving an audio signal to each conference participant by a left audio signal and a right audio signal, wherein an adding means for each conference participant for adding the left audio signal and the right audio signal from the conference participant; Ratio dividing means for dividing each of the added audio signals into a first audio signal and a second audio signal according to an arbitrary ratio, and a first audio signal from each conference participant. And a first voice arithmetic circuit for removing the own voice signal to obtain a voice signal for each conference participant;
A second voice operation circuit for mixing the second voice signals from each conference participant and removing its own voice signal to obtain a voice signal for each conference participant; and a first voice operation circuit for each conference participant. And a voice reproducing means for each conference participant for reproducing left and right voices based on the voice signal of the calculation result and the voice signal of the second calculation result.

[Industrial applications]

The present invention relates to an audio conference apparatus, and more particularly to a stereo audio conference apparatus that facilitates identification of a speaker.

2. Description of the Related Art A voice conference apparatus is one in which three or more people at remote locations hold a conference by transmitting and receiving voice via a telephone line, and are about to be widely used.

In such a voice conference apparatus, it is required that even if many conference participants speak at the same time, the speaker can be easily specified.

[Conventional technology]

In the audio conference apparatus, three or more conference participants at remote locations can communicate in a conference format by adding and calculating the voice of the conference participants.

In the conventional voice conference apparatus, one voice channel is allocated to each conference participant, and the voices of all conference participants are distributed and transmitted to each participant via this voice channel. Has become.

FIG. 4 shows the configuration of a conventional audio conference device.

The audio conference device 11 includes an adder 12 and subtracters 13, 14, and 15. Audio A, audio B, from multiple conference participants A, B, C
The voice C has one voice channel 101, 102,
The voice conference device 11 is reached by 103. Audio Conference Equipment 1
In step 1, the audio of each of the channels 101, 102 and 103 is added by the adder 12 to generate an addition output S. And voice A, voice
The own voice is removed by performing the operations of (SA), (SB), and (SC) in subtractors 13, 14, and 15 provided corresponding to B and voice C, respectively. Voice B +
Create C, A + C, A + B, and channel
Send back to conference participants A, B, C via 201, 202, 203.

[Problems to be solved by the invention]

In the conventional audio conference apparatus, one audio channel is allocated to each conference participant.

Therefore, if the number of conference participants is large, if many conference participants speak simultaneously, the voice will all be heard from one channel, making it difficult to identify who is the speaker. There was a problem.

For example, in the case of FIG. 4, the voices of the conference participants B and C are transmitted to the conference participant A via the same channel 201. Since the sound is heard from the speaker, when a plurality of conference participants speak simultaneously, it is not easy to determine who is speaking.

An object of the present invention is to solve such a problem of the prior art, and an object of the present invention is to provide a voice conference apparatus that facilitates discrimination of speakers by giving directions to the voices of the speakers. And

[Means for solving the problem]

As shown in FIG. 1 (a), the present invention provides a voice conference apparatus for transmitting and receiving between three or more conference participants by using a left audio signal and a right audio signal. And dividing the audio signal obtained by adding the left audio signal and the right audio signal by the adding means (1) into first and second audio signals at different rates corresponding to the conference participants. Means (2) and said ratio dividing means (2)
The first voice signal of each conference participant divided by the above is input and added, and the first voice signal corresponding to the conference participant who becomes a receiver is subtracted from the voice signal of the added output, and the reception is performed. A first voice operation circuit (3) for transmitting as a left voice signal to a conference participant to be a participant, and the second voice signal of each conference participant divided by the ratio dividing means (2). And subtracting the second audio signal corresponding to the conference participant to be the receiver from the audio signal of the added output, and transmitting the result as the right audio signal to the conference participant to be the receiver.
And a voice operation circuit (4).

Also, as shown in FIG. 1 (b), the present invention shows a sound transmitted and received between three or more conference participants by a sum signal and a difference signal of a left audio signal and a right audio signal, as shown in FIG. A conference device for dividing the sum signal from the conference participant into first and second audio signals at different rates according to the conference participant; The first audio signal of each conference participant divided according to (2) is input and added, and the first audio signal corresponding to the conference participant to be a listener is subtracted from the added output audio signal. A first voice operation circuit (3) for generating a left voice signal to a conference participant serving as the receiver, and the ratio dividing means (2)
The second voice signal of each conference participant divided by the above is input and added, and the second voice signal corresponding to the conference participant who becomes a receiver is subtracted from the voice signal of the added output, and the reception is performed. A second voice arithmetic circuit (4) for making a right voice signal to a conference participant to be a participant, the left voice signal from the first voice arithmetic circuit (3), and the second voice arithmetic circuit (4). ) Is added to and subtracted from the right audio signal, and the addition and subtraction means (6) for transmitting the sum signal and the difference signal of the left audio signal and the right audio signal to the conference participant serving as the listener. It is provided.

[Action]

According to the first aspect of the present invention, an audio signal obtained by adding a left audio signal and a right audio signal from a conference participant is divided into first and second audio signals at different ratios corresponding to the conference participants. Then, the first voice signal of each conference participant is input and added, and a first voice operation for subtracting the first voice signal corresponding to the conference participant to be a receiver from the voice signal of the added output is performed. Do
The first voice calculation result is transmitted as a left voice signal to the conference participant serving as the receiver, and the second voice calculation result of each conference participant is transmitted.
And performs a second voice operation of subtracting the second voice signal corresponding to the conference participant to be the receiver from the voice signal of the added output, and the second voice calculation result Is transmitted to the conference participant as the receiver as a right audio signal.

Therefore, according to the present invention, in a voice conference apparatus for transmitting and receiving between three or more conference participants using a left voice signal and a right voice signal, it is possible to give directions to the voices of the speakers, The speaker at the time can be easily identified.

In the invention of claim 2, the sum signal of the left audio signal and the right audio signal from the conference participant is divided into the first and second audio signals at different ratios corresponding to the conference participant. Then, the first voice signal of each conference participant is input and added, and the first voice signal corresponding to the conference participant who becomes the receiver is subtracted from the voice signal of the added output to become the receiver. A first voice operation as a left voice signal to a conference participant;
The second audio signal corresponding to the conference participant to be the receiver is subtracted from the audio signal of the added output, and the right audio signal to the conference participant to be the receiver is added to the input audio signal. Performing a second voice calculation, and adding and subtracting the left voice signal of the first voice calculation result and the right voice signal of the second voice calculation result to obtain a left voice signal and a right voice signal. Are transmitted to the conference participant who is the receiver as the sum signal and the difference signal.

Therefore, according to the present invention, in a voice conference apparatus for transmitting and receiving between three or more conference participants by using a sum signal and a difference signal of a left voice signal and a right voice signal, the voices of the speakers have different directions. Can be given, and it becomes easy to determine the speaker at the time of simultaneous speech.

〔Example〕

In the present invention, when performing the arithmetic processing in the audio conference device, the audio channel allocated to each conference participant is set to a stereo system with two channels, and the distribution ratio of the left audio and the right audio is changed for each conference participant. By adding and distributing, it becomes easy to determine who is speaking to the conference participant who is listening to the conference audio.

In a conventional audio conference, a terminal is normally capable of transmitting and receiving only one channel of monaural audio, such as an analog telephone terminal. The number of channels was one, and only addition and distribution of monaural sound could be performed.

However, in the case of ISDN terminals that have been put into practical use in recent years, it has become possible to use two channels for transmitting and receiving voice in one terminal. Therefore, two audio channels are used, one for the left audio signal and one for the right audio signal.
Sends and receives stereo-type audio to which channels are assigned, or sends and receives stereo-type audio to which one channel is assigned for each of a sum signal of left audio and right audio and a difference signal of left audio and right audio. It can be performed.

Then, in the audio conference apparatus, by adding and distributing such stereo type audio, it is possible to easily determine who is the audio conference participant who has spoken.

For example, when three people A, B, and C are in a conference, the voice of the conference participant B is distributed to the conference participant A as the left voice signal, and the voice of the conference participant C is distributed as the right voice signal. In this case, if the voice from the left is heard, the speaker is B, and if the voice from the right is heard, the speaker is C.

If there are four participants in the audio conference, for example, A, B, C,
When four persons D are in a conference, the audio of the conference participant B is used as the left audio signal and the audio of the conference participant C is used as the left audio signal and the right audio signal for the conference participant A. When the voice of the conference participant D is distributed as the right voice signal,
The conference participant A can immediately determine that the left voice is the conference participant B, the center voice is the conference participant C, and the right voice is the conference participant D.

Similarly, when the number of voice participants is five or more, when adding and calculating the voice of each conference participant and distributing, the ratio of the left voice signal and the right voice signal of the voice of each conference participant is changed. , Left, diagonally forward left, center, diagonally right forward, right, etc., it is possible to give directionality to the speaker's voice to the conference participants, and similarly, it is possible to determine who the speaker is. It can be easily determined.

FIG. 2 shows an embodiment of the present invention, in which three conference participants A, B, and C are used, and voices from each conference participant and arithmetic operations on each conference participant are performed. This example illustrates a case in which audio is transmitted and received on two channels, each of which is a left channel and a right channel.

In the figure, a stereo type audio conference apparatus 100 includes an addition circuit 30.
1,302,303 and weighting multiplication circuits 311,321,312,322,31
3, 323, and a left channel voice operation circuit 310 and a right channel voice operation circuit 320. The left-channel audio operation circuit 310 has an addition circuit 21 and subtraction circuits 22, 23, and 24, and each channel audio operation circuit 320 has an addition circuit 31 and subtraction circuits 32, 33, and 34.

In FIG. 2, it is assumed that the audio of the conference participant A is equally divided into left and right, and the left audio is input to the stereo audio conference device 100 from the channel 101 and the right audio is input to the stereo audio conference device 100 from the channel 111.

The left and right audio signals of the conference participant A input to the audio conference device 100 via the channels 101 and 111 are added by the adder 301 to generate an audio A signal. Audio A signal is a multiplier
After being given a ratio of 0.5 for the left voice and for the right voice by 311 and 321 respectively, they are input to the voice operation circuits 310 and 320 of the left channel and the right channel, respectively.

Similarly, the left and right audio signals of the conference participants BB are added to the adder 30.
2 to produce the audio B signal. The audio B signal is given the ratios 1 and 0 for the left audio and the right audio by the multipliers 312 and 322, respectively, and then input to the audio arithmetic circuits 310 and 320 for the left and right channels.

The left and right audio signals of the conference participant C are added to the adder 303.
To produce a voice C signal. The audio C signal is given the ratios 0 and 1 for the left audio and the right audio by the multipliers 313 and 323, respectively.
The signals are input to the respective voice operation circuits 310 and 320 of the right channel.

Left channel audio amplifier 310 and right channel audio amplifier 320
Is an adder circuit as in the case of the conventional example shown in FIG.
After adding the audio from each conference participant at 21,31,
The subtracters 22, 23, 24 and 32, 33, 34 respectively subtract their own voices and distribute them to each conference participant. For the conference participant A, (B × 1) ) + (C ×
0), the (B × 0) +
A (C × 1) audio signal is transmitted.

Each conference participant's seat is provided with a left audio playback device and a right audio playback device. The left audio playback device plays a left channel audio signal, and the right audio playback device sends a right audio playback device. The audio signal of the channel is reproduced.

Therefore, the conference participant A can hear the voice of the conference participant B from the left direction, and can hear the voice of the conference participant C from the right direction, and it is easy to determine the speaker.

Similarly, for the conference participant B, an audio signal of (A × 0.5) + (C × 0) is input to the left channel 202 and the right channel 301 is output.
(A × 0.5) + (C × 1), the conference participant B hears the voice of conference participant A from the center and hears the voice of conference participant C from the right. And it is easy to judge the speaker.

Similarly, for the conference participant C, the left channel 20
(A × 0.5) + (B × 1) audio signal in right channel
Since an audio signal of (A × 0.5) + (B × 0) is transmitted to 303, the conference participant C hears the audio of the conference participant A from the center direction and hears the audio of the conference participant B from the left direction. And it is easy to determine the speaker.

Even if there are four or more conference participants, the multiplication circuit 31
As in the case of 1,312,313,321,322,323, a multiplier can be assigned to each conference participant to change the ratio of the left and right voices of each conference participant.

It is also easy to arbitrarily set the ratio of left and right sounds from an external control device or the like according to the number of conference participants.

Further, it goes without saying that the arithmetic circuits such as the adder, the multiplier and the subtractor in the present embodiment may be constituted by analog circuits or digital circuits.

FIG. 3 shows another embodiment of the present invention, and illustrates a case where the present invention is applied to a stereo audio terminal. The same components as those in FIG.
0 is a stereo audio conference device, 211, 212, and 213 are addition circuits, and 221, 222, and 223 are subtraction circuits.

In the embodiment shown in FIG. 3, the audio signal transmitted from each conference participant is composed of a (left + right) audio signal and a (left-right) audio signal, and the received signal for each conference participant is reproduced. A case is shown in which the device is a stereo audio terminal that reproduces left audio and right audio in response to (left + right) audio signals and (left-right) audio signals.

In this case, audio output circuits 211, 212, 213 and audio subtraction circuit 22
1, 222, 223 are required, and although not shown in FIG. 3, (Left +
An addition circuit and a subtraction circuit for adding and subtracting the (right) audio signal and the (left-right) audio signal, respectively, and performing appropriate weighting are required. By using only the (left + right) audio signal on the output side and connecting a stereo type audio conference device as shown in FIG. Can be played back, so that even a stereo type audio terminal can participate in a conference.

In FIG. 3, the (left + right) audio signal of the conference participant A is input to the multipliers 311 and 321 from the channel 501 so that the left and right audio signals are respectively used for the left audio and the right audio.
After being given 0.5, it is input to the voice operation circuits 310 and 320 of the left channel and the right channel, respectively.

Similarly, the (left + right) audio signal of the conference participant B is input to the multipliers 312 and 322 from the channel 502 to be given ratios 1 and 0 for the left audio and the right audio, respectively. The signals are input to the voice operation circuits 310 and 320 of the channel and the right channel, respectively.

Further, the (left + right) audio signal of the conference participant C is input to the multipliers 313 and 323 from the channel 503 to be given ratios 0 and 1 for the left audio and the right audio, respectively. And the respective voice operation circuits 310 and 320 of the right channel.

Left channel audio amplifier 310 and right channel audio amplifier 320
Is an adder circuit as in the case of the conventional example shown in FIG.
After adding the audio from each conference participant at 21,31,
The subtracters 22, 23, 24 and 32, 33, 34 respectively subtract their own voices and distribute them to the conference participants, so that for the conference participants A, the channel 201 is (B × 1). + (C ×
0) is input to the channel 301 as (B × 0) + (C
× 1) audio signal is transmitted.

Similarly, an audio signal of (A × 0.5) + (C × 0) is sent to channel 202 and an audio signal of (A × 0.5) + (C × 1) is sent to channel 302 to conference participant B. Is done.

Further, to the conference participant C, an audio signal of (A × 0.5) + (B × 1) is transmitted to the channel 203, and an audio signal of (A × 0.5) + (B × 0) is transmitted to the channel 303. You.

The adder 211 is connected to the audio signal of the channel 201 and the channel 301.
The subtraction circuit 221 subtracts the audio signal of the channel 201 and the audio signal of the channel 301 to add the (B + C) audio signal to the channel 401 (left +
Right) Output as an audio signal and output to channel 402 (BC)
Is output as a (left-right) audio signal.

Similarly, the addition circuit 212 adds the audio signal of the channel 202 and the audio signal of the channel 302, and the subtraction circuit 222
By subtracting the audio signal of 202 and the audio signal of channel 302, the audio signal of (A + C) is output as a (left + right) audio signal to channel 402, and the (−) is output to channel 412.
The audio signal of (C) is output as a (left-right) audio signal.

Further, the addition circuit 213 adds the audio signal of the channel 203 and the audio signal of the channel 303, and the subtraction circuit 223 adds
By subtracting the audio signal of 203 and the audio signal of channel 303, the audio signal of (A + B) is output as a (left + right) audio signal to channel 403, and the audio signal of (B) is output to channel 413 as (left -Right) Output as audio signal.

The conference participant A's terminal adds and subtracts the (left + right) audio signal (B + C) and the (left-right) audio signal (BC), and weights the signal by 1/2. Play B as voice and play C as right voice. Accordingly, since the conference participant A can hear the voice of the conference participant B from the left direction and hear the voice of the conference participant C from the right direction, it is easy to determine the speaker.

Similarly, at the terminal of conference participant B, (left + right)
Audio signal (A + C) and (left-right) audio signal (-C)
Are added and subtracted, and weighted to 1/2, A × 0.5 is reproduced as the left voice and A × 0.5 as the right voice.
Play 0.5 + C. Therefore, the conference participant B hears the voice of the conference participant A from the center, and the conference participant C from the right.
, It is easy to determine the speaker.

Further, in the terminal of the conference participant C, (left + right)
By adding and subtracting the audio signal (A + B) and the audio signal (B) of (left-right) and weighting them by 1/2,
Play A × 0.5 + B as left voice and A × as right voice
Play 0.5. Accordingly, since the conference participant C can hear the voice of the conference participant A from the center and hear the voice of the conference participant B from the left, it is easy to determine the speaker.

In the embodiment of FIG. 3, it is apparent that the same effect can be obtained even if one of the inputs from the conference participants A, B, and C is a (right-left) audio signal.

〔The invention's effect〕

As described above, according to the present invention, even if a voice conference is performed by a large number of conference participants and a large number of conference participants speak simultaneously, the voices of the speakers can be heard from different directions. Can easily determine who the speaker is, so that the audio conference can proceed smoothly.

[Brief description of the drawings]

FIGS. 1 (a) and 1 (b) are diagrams showing the principle configuration of the present invention,
FIG. 2 is a diagram showing one embodiment of the present invention, FIG. 3 is a diagram showing another embodiment of the present invention, and FIG. 4 is a diagram showing a configuration of a conventional voice conference apparatus. 1 is an adding means, 2 is a ratio dividing means, 3 and 4 are audio operation circuits, 5 and 7 are audio reproducing means, and 6 is an adding / subtracting means.

Claims (2)

(57) [Claims] 1. An audio conference apparatus for transmitting and receiving between three or more conference participants using a left audio signal and a right audio signal, wherein the left audio signal and the right audio signal from the conference participants are added. A ratio dividing means (2) corresponding to the conference participant for dividing the audio signal added in (1) into first and second audio signals at different ratios corresponding to the conference participant; The first audio signal of each divided conference participant is input and added, and the first audio signal corresponding to the conference participant to be a receiver is subtracted from the added output audio signal to obtain the listener. A first voice operation circuit (3) for transmitting as a left voice signal to a conference participant, and the second voice signal of each conference participant divided by the ratio dividing means (2). And add the conference output to the receiver from the audio signal of the added output. A second voice arithmetic circuit (4) for subtracting the second voice signal corresponding to the user and transmitting the second voice signal as a right voice signal to a conference participant serving as the receiver. . 2. A voice conference apparatus for transmitting and receiving between three or more conference participants using a sum signal and a difference signal of a left audio signal and a right audio signal, wherein the sum signal from the conference participants is transmitted to a conference. Ratio dividing means (2) corresponding to a conference participant for dividing into first and second audio signals at different ratios for the participant, and the first participant of each conference participant divided by the ratio dividing means (2) The first audio signal corresponding to the conference participant who becomes the receiver is subtracted from the audio signal of the addition output, and the left audio signal to the conference participant who becomes the receiver is added to the input audio signal. A first voice arithmetic circuit (3), and the second voice signal of each conference participant divided by the ratio dividing means (2) are inputted and added. The second audio signal corresponding to the conference participant to be A second voice operation circuit (4) for making a right voice signal to a conference participant; the left voice signal from the first voice calculation circuit (3); and the second voice calculation circuit (4). An addition / subtraction means (6) for adding and subtracting the right audio signal and the sum of the left audio signal and the right audio signal and transmitting the sum signal and the difference signal to the conference participant serving as the listener. A voice conference device characterized by the above-mentioned.