JPH08116353A - Communication conference terminal equipment - Google Patents

Abstract

PURPOSE: To provide a communication conference terminal equipment capable of efficiently operating a communication conference in which plural members participate. CONSTITUTION: The gain of variable gain amplifiers 32, 35 and 37 for amplifying voice signals larger than a prescribed level among the voice signals inputted from plural microphones 2-4 is set at a large value. Thus, the voice signals of a main speaker are emphasized and the voice of the main speaker is clearly listened to in an opposite terminal. Also, since the signals of a non voice band included in signals inputted from the microphones 2-4 are removed in a low-pass filter 39, the clear voice from which noise other than the voice is suppressed is obtained in the opposite terminal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication conference terminal device which has at least a communication conference terminal function, a voice transmitting / receiving function, and a moving image transmitting / receiving function, and which transmits voice signals input from a plurality of microphones to a partner terminal. .

[0002]

2. Description of the Related Art In recent years, a communication conference terminal device capable of exchanging voice information and moving image information with a partner terminal and performing a predetermined conference communication has been considered promising as a terminal utilizing ISDN. System has been proposed.

In general, in the conference communication performed by this communication conference terminal device, each communication conference terminal device can be used by a plurality of members. In that case, for example, one large video monitor device is used. In addition to being shared, it is equipped with multiple microphones so that the members' comments on the terminal can be picked up efficiently.

Further, the video camera device for photographing the state of the self-terminal side is provided with a function capable of moving the photographing frame vertically and horizontally so that the state of the participating members on the self-terminal side can be photographed without arousing. I am trying.

[0005]

However, such a communication conference terminal device has the following disadvantages.

That is, when a plurality of members participate, the voices of members other than the main speaker are also picked up by the microphone, which may cause a situation in which the main speaker's utterance cannot be heard well on the partner terminal.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a communication conference terminal device capable of efficiently managing a communication conference in which a plurality of members participate.

[0008]

The present invention provides at least the following:
In a communication conference terminal device that has a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function, and transmits voice signals input from multiple microphones to a partner terminal, multiple voice signals input from multiple microphones A plurality of audio level determination means for determining that each is higher than a predetermined level, and a plurality of audio signals respectively input from a plurality of microphones are amplified, while a corresponding audio level among the plurality of audio level determination means When the judging means judges that the sound level is higher than the predetermined level, the first gain is set, and the corresponding sound level judging means out of the plurality of sound level judging means is below the predetermined level. A plurality of variable gain amplifiers for which the second gain is set when the determination is made, and outputs of the plurality of variable gain amplifiers An adder for adding the issue, in which a control means for transmitting to the remote terminal the output signal of the adder as the transmission audio signal.

Further, in a communication conference terminal device which has at least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function, and which transmits voice signals input from a plurality of microphones to a partner terminal, the plurality of microphones respectively An adder for adding a plurality of input voice signals, a low-pass filter means for extracting a signal in a predetermined voice band from an output signal of the adder, and an output signal of the low-pass filter means transmitted to a partner terminal as a transmission voice signal It is provided with a control means for controlling.

Further, in a communication conference terminal device which has at least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function, and which transmits voice signals input from a plurality of microphones to a partner terminal, the plurality of microphones are used respectively. A plurality of audio level determination means for determining that each of the plurality of input audio signals is higher than a predetermined level, and a plurality of audio signals respectively input from a plurality of microphones are amplified, while the plurality of audio level determinations are performed. When it is determined that the corresponding sound level determination means out of the plurality of means is higher than the predetermined level, the first gain is set, and the corresponding sound level determination means among the plurality of sound level determination means is predetermined. A plurality of variable gain amplifiers for which a second gain is set when it is determined that the level is below the level, An adder for adding output signals of a plurality of variable gain amplifiers, a low-pass filter means for extracting a signal in a predetermined voice band from the output signal of the adder, and an output signal of the low-pass filter means as a transmission voice signal. It is provided with a control means for transmitting to the terminal.

Further, in a communication conference terminal device which has at least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function, and which transmits voice signals input from a plurality of microphones to a partner terminal, the plurality of microphones are used respectively. A plurality of audio level determination means for determining that each of the plurality of input audio signals is higher than a predetermined level, and a plurality of audio signals respectively input from a plurality of microphones are amplified, while the plurality of audio level determinations are performed. When it is determined that the corresponding sound level determination means out of the plurality of means is higher than the predetermined level, the first gain is set, and the corresponding sound level determination means among the plurality of sound level determination means is predetermined. A plurality of variable gain amplifiers for which a second gain is set when it is determined that the level is below the level, The adder for adding the output signals of the plurality of variable gain amplifiers, the low-pass filter means for extracting the signal of the predetermined voice band from the output signal of the adder, and the frequency characteristic thereof can be changed, and the low-pass filter means The output signal is transmitted to the partner terminal as a transmission voice signal, and the control means for adjusting the frequency characteristic of the low-pass filter means is provided by a command.

Further, in a communication conference terminal device which has at least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function, and which transmits an audio signal input from a plurality of microphones to a partner terminal, the plurality of microphones respectively A plurality of audio level determination means for determining that each of the plurality of input audio signals is higher than a predetermined level, and a plurality of audio signals respectively input from a plurality of microphones are amplified, while the plurality of audio level determinations are performed. When it is determined that the corresponding sound level determination means out of the plurality of means is higher than the predetermined level, the first gain is set, and the corresponding sound level determination means among the plurality of sound level determination means is predetermined. A plurality of variable gain amplifiers for which a second gain is set when it is determined that the level is below the level, An adder for adding output signals of a plurality of variable gain amplifiers, a low-pass filter means for extracting a signal in a predetermined voice band from the output signal of the adder, and an output signal of the low-pass filter means as a transmission voice signal. It is provided with control means for transmitting to the terminal and adjusting the output gain of the adder by a command.

Further, in a communication conference terminal device which has at least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function, and which transmits voice signals input from a plurality of microphones to a partner terminal, the plurality of microphones respectively A plurality of audio level determination means for determining that each of the plurality of input audio signals is higher than a predetermined level, and a plurality of audio signals respectively input from a plurality of microphones are amplified, while the plurality of audio level determinations are performed. When it is determined that the corresponding sound level determination means out of the plurality of means is higher than the predetermined level, the first gain is set, and the corresponding sound level determination means among the plurality of sound level determination means is predetermined. A plurality of variable gain amplifiers for which a second gain is set when it is determined that the level is below the level, The adder for adding the output signals of the plurality of variable gain amplifiers, the low-pass filter means for extracting the signal of the predetermined voice band from the output signal of the adder, and the frequency characteristic thereof can be changed, and the low-pass filter means The output signal is transmitted to the other terminal as a transmission voice signal, and a control means for adjusting the frequency characteristic of the low-pass filter means and the output gain of the adder by a command is provided.

Further, in a communication conference terminal device which has at least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function, and which transmits an audio signal input from a plurality of microphones to a partner terminal, the plurality of microphones respectively Of the plurality of input audio signals, the largest audio signal is determined, the audio signal is multiplied by the first coefficient, and the other audio signals are multiplied by the second coefficient and the first coefficient is multiplied. An audio signal calculation means for subtracting the sum of the audio signals multiplied by the second coefficient from the audio signal, a low-pass filter means for extracting a signal in a predetermined audio band from the output signal of the audio signal operation means, and the low-pass filter. It is provided with a control means for transmitting the output signal of the means to the partner terminal as a transmission voice signal.

Further, in a communication conference terminal device which has at least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function, and which transmits an audio signal input from a plurality of microphones to a partner terminal, the plurality of microphones respectively Of the plurality of input audio signals, the largest audio signal is determined, the audio signal is multiplied by the first coefficient, and the other audio signals are multiplied by the second coefficient and the first coefficient is multiplied. A voice signal calculating means for subtracting the sum of the voice signals multiplied by the second coefficient from the voice signal, and a signal in a predetermined voice band can be extracted from the output signal of the voice signal calculating means, and its frequency characteristic can be changed. The low-pass filter means and the output signal of the low-pass filter means are transmitted to a partner terminal as a transmission voice signal, and the low-pass filter means is instructed by the command. Frequency characteristic of the filter means, and, in which a control means for adjusting the output gain of the audio signal calculating means.

[0016]

Therefore, the gain of the variable gain amplifier that amplifies a voice signal larger than a predetermined level among the voice signals input from a plurality of microphones is set to a large value, so that the voice signal of the main speaker is emphasized. Therefore, the voice of the main speaker can be clearly heard on the partner terminal. Further, since the signal in the non-voice band included in the signal input from the microphone is removed, the other terminal can obtain clear voice in which noise other than voice is suppressed.

Further, since the frequency characteristic and the volume of the voice signal sent to the partner terminal can be adjusted appropriately, the partner terminal side can obtain better quality voice.

Further, among the voice signals input from the plurality of microphones, voice signals other than the voice signal caused by the speech of the main speaker can be removed to some extent.
You can clearly hear the statements of the main speaker.

[0019]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 shows a communication conference terminal device according to an embodiment of the present invention. This communication conference terminal device is C
CITT Recommendation H.264 The video conference communication function defined by 320 is provided, and ISDN is used as a transmission line.

In this figure, this communication conference terminal device is
The ISDN is used as a transmission path, and the main body device 1 has three microphones 2, 3, 4, one video monitor device 5, one video camera device 6, a pair of speaker systems 7, and this. An operation display device 8 for operating the communication conference terminal device is connected.

The operation display device 8 is, for example, 640.
It is composed of a liquid crystal display device having a display resolution of about × 480 (up to 1000 × 1000) dots and a touch panel device provided on the display screen of the liquid crystal display device. The display screen of the liquid crystal display device is transparent to the touch panel device. It is displayed through the sensor surface.

Normally, an operation screen on which a plurality of operation symbols and guidance messages are arranged in an appropriate manner is displayed on the liquid crystal display device, and the user touches the operation symbol displayed on the operation screen with the pen 9. By operating, any operation can be performed.

FIG. 2 shows an example of the configuration of the main body device 2.

In the figure, the system control unit 11 is for controlling the operation of each unit of the communication conference terminal device and for executing the TV conference communication control procedure processing on the information channel (B channel), and the like. The (read only memory) 12 is for storing a part of the control processing program executed by the system control unit 11 and various data referred to when executing this program, and is a RAM (random memory). Access memory) 1
Reference numeral 3 constitutes a work area or the like of the system control unit 11.

The clock circuit 14 is for outputting the current time information, and the image processing section 15 is, for example, the image reduction / enlargement processing, the still image processing of the photographing screen, and the encoding / decoding of the still image. It is for executing various image processing necessary for the device functions provided by this communication conference terminal device, such as a digitization process (JPEG method) and a statistical process of an image.

The magnetic disk device 16 is for storing program data such as other control programs and application programs executed by the system controller 11, or other various data. , For example, a still image camera device,
It is for inputting a still image.

The voice input / output device 18 is for exchanging voice information with a partner terminal to realize a conversation between users. In this case, the microphones 2, 3, 4 and It is composed of the speaker system 7 and their drive devices. The voice CODEC 19 converts the analog voice signal input from the voice input / output device 18 into the corresponding digital voice data, converts the received digital voice data into the corresponding analog voice signal, and outputs the voice input / output device 1
8 is output. The voice control unit 20 is for controlling the operation of the voice input / output device 18.

The video CODEC 21 CITs the NTSC type video signal output from the video camera device 6.
Recommendation H.T. The video information is coded and compressed by the H.261 coding system to form video information, and the video information in the coded and compressed state is decoded and converted into a video signal. The video signal converted and formed by the video CODEC 21 is output to the display control unit 22. Also, the video signal output from the video camera device 6 is
It is also added to the display control unit 22. Display control unit 22
Is for controlling the contents of the display screen of the video monitor device 5. The video camera control unit 23 is for controlling the camera angle of the video camera device 6 and the like.

The ISDN interface control unit 24 connects the communication conference terminal device to the ISDN, integrates the signal processing function of layer 1, the D channel (signal channel) signal and the two B channel (information channel) signals. / It has a separation function.

The D-channel transmission control unit 25 has a call control procedure function for a signal channel and a multiple call control function, and the multiplexing / demultiplexing control unit 26 is a CCIT.
Recommendation H.T. 221, data multiplexing / separation function,
Also, it has a data frame synchronization function, and digital audio data, digital video data, and various general-purpose data are added to the connection end on the separation side, and the connection on the multiplexing side. The end is connected to the ISDN interface control unit 24.

These system control unit 11 and ROM 1
2, RAM 13, clock circuit 14, image processing unit 15, magnetic disk device 16, operation display device 8, still image input device 1
7, audio CODEC 19, audio control unit 20, video CO
DEC 21, display control unit 22, video camera control unit 2
3, the D channel transmission controller 25, and the multiplexer / demultiplexer 26 are connected to a system bus 27, and data is exchanged between these respective elements mainly via the system bus 27. .

Also, the multiplexer / demultiplexer 26 and the voice COD
Audio data is exchanged with the EC 19, and video data is exchanged with the multiplexer / demultiplexer 26 and the video CODEC 21.

FIG. 3 shows an example of a circuit for processing the audio signals from the microphones 2, 3 and 4 in the audio input / output device 18.

Audio signal SA1 output from the microphone 2
Are added to the audio level determination unit 31 and the variable gain amplifier 32. The audio level determination unit 31 determines the audio signal S
If it is determined whether the level of A1 is equal to or higher than a predetermined value, and if the level of the audio signal SA1 is equal to or higher than the predetermined value, the gain control signal SS1 output to the variable gain amplifier 32 is output. Is set to a predetermined main audio gain value Gm, and when the level of the audio signal SA1 is less than the predetermined value, the value of the gain control signal SS1 is set to a predetermined non-main audio gain value Gn. Is. here,
It is set to Gm> Gn.

The variable gain amplifier 32 outputs the audio signal SA1.
Is amplified with a gain corresponding to the gain control signal SS1, and its output signal SA1a is added to one input terminal of the adder 33.

Audio signal SA2 output from the microphone 3
Are added to the audio level determination unit 34 and the variable gain amplifier 35. The audio level determination unit 34 determines the audio signal S
If it is determined whether the level of A2 is equal to or higher than a predetermined value, and if the level of the audio signal SA2 is equal to or higher than the predetermined value, the gain control signal SS2 output to the variable gain amplifier 35 is output. Is set to a predetermined main audio gain value Gm, and when the level of the audio signal SA2 is less than the predetermined value, the value of the gain control signal SS2 is set to a predetermined non-main audio gain value Gn. Is. here,
It is set to Gm> Gn.

The variable gain amplifier 35 outputs the audio signal SA2.
Is amplified with a gain corresponding to the gain control signal SS2, and its output signal SA2a is added to one input terminal of the adder 33.

Audio signal SA3 output from the microphone 4
Is added to the audio level determination unit 36 and the variable gain amplifier 37. The audio level determination unit 36 determines the audio signal S
When it is determined whether the level of A3 is equal to or higher than a predetermined value, and it is determined that the level of the audio signal SA3 is equal to or higher than the predetermined value, the gain control signal SS3 output to the variable gain amplifier 37. Is set to a predetermined main audio gain value Gm, and when the level of the audio signal SA3 is less than the predetermined value, the value of the gain control signal SS3 is set to a predetermined non-main audio gain value Gn. Is. here,
It is set to Gm> Gn.

The variable gain amplifier 37 outputs the audio signal SA3.
Is amplified with a gain corresponding to the gain control signal SS3, and its output signal SA3a is added to one input terminal of the adder 33.

The adder 33 outputs signals SA1a, SA2a,
SA3a is added, and its output signal is added to the variable gain amplifier 38. Variable gain amplifier 38
Is a gain control signal S added from the system control unit 11.
The input signal is amplified with a gain corresponding to C1, and its output signal is added to the low-pass filter 39.

The low-pass filter 39 extracts a signal in a predetermined audio frequency band from the input signal, and outputs the output signal as an audio signal SA to the next-stage device (audio CODEC 19 in this case). To be done. Further, the low-pass filter 39 changes the center frequency of the extracted audio frequency band in response to the characteristic control signal SC2 added from the system control unit 11.

If a member sitting in front of the microphone 2 speaks in the conference room, the audio signal SA1 output from the microphone 2 has a sufficiently high level and is output from the microphones 3 and 4. Voice signal SA2, SA
Although 3 includes the signal component of the speech of the other members, it has a relatively low level.

Therefore, in this case, the gain control signal SS1 output from the audio level determination unit 31 is set to the main audio gain value Gm, and the gain control signals SS2 and SS3 output from the audio level determination units 34 and 36. Is set to the non-main voice gain value Gn.

As a result, the audio signal SA1 becomes a signal SA1a amplified by the variable gain amplifier 32 with a gain corresponding to the main audio gain value Gm, and also the audio signal SA1.
2, SA3 are signals SA2 amplified by the gains corresponding to the non-main voice gain value Gn by the variable gain amplifiers 35 and 37.
a, SA3a.

Thereby, in this case, the adder 33
The signal output from is the audio signal SA of the main speaker.
1 is included in the largest proportion, the variable gain amplifier 3
The voice signal SA, which is amplified by 8 and in which the frequency components other than the voice band are removed by the low-pass filter 39, contains the voice of the main speaker most, and the voice of other members such as chats is almost included. There will be no state.

Therefore, when this voice signal SA is transmitted to the partner terminal, the received voice obtained at the partner terminal is such that the main speaker's voice is loudest and the other members' voices are hardly included. As a result, the other terminal can clearly hear the voice of the main speaker.

Further, the system control section 11 can adjust the level of the audio signal SA by appropriately setting the value of the gain control signal SC1, and the characteristic control signal SC
The frequency characteristic of the audio signal SA can be adjusted by appropriately setting the value of 2.

Therefore, the operation display device 8 can display an operation screen or the like on which the user can appropriately adjust the volume and frequency characteristics to allow the user to arbitrarily adjust the volume and frequency characteristics.

In the teleconference terminal device, the call control procedure in ISDN is executed to perform the call control operation, and in the B channel, the TTC standard JT-H. 22
Data is exchanged in the multi-frame format specified in 1.

As shown in FIG. 4, one multi-frame MFL includes eight sub-multi-frames SMF1 to SMF.
8 sub-multiframes SMF1 to 8
Each SMF 8 is composed of two frames. That is, one multi-frame MFL is composed of 16 frames FLM0 to FLM15.

Each frame FLM0 to FLM15
As shown in FIG. 5, consists of data of 80 octets, and the bit positions in which these octets are arranged in the bit order form subchannels SCH1 to SCH8.

The 8th bit of the 1st octet to the 8th octet is the frame synchronization signal (Frame Ali).
The 8th bit of the 9th octet to the 16th octet constitutes a bit rate allocation signal (Bit rate Allocation).
Signal) BAS. That is, the sub-channel SCH8 is assigned to the eighth bit of the 17th octet to the 80th octet, and this portion is applied to the application channel AC (Application Channel).
el) is sometimes called. Also, sub-channel SC
In the 17th to 24th octets of H8, data of an encrypted channel for exchanging key information for encrypting data may be set (optional).

In this way, the frame synchronization signal FAS
8 bits are arranged in one frame FLM0 to FLM15, and the bit allocation is configured in units of multiframe MFL as shown in FIG.

That is, even frames FLM0, FLM
2, ..., The second to eighth octets of the FLM 14, and the odd frames FLM1, FLM3 ,.
A horizontal synchronization signal composed of an 8-bit data pattern "001101111" is arranged in the FLM 15, and a vertical synchronization composed of a 6-bit data pattern "001011" is arranged in the first octet of the odd-numbered frames FLM1, FLM3, ..., FLM11. A sync signal is placed.

By detecting the horizontal synchronizing signal and the vertical synchronizing signal, the synchronization of one multi-frame MFL can be detected.

The 0th frame, the 2nd frame, the 4th frame
Bits N1, N2, N3, N4, N5 of the first octet of the frame, the sixth frame and the eighth frame are used to indicate the multi-frame number. Of these, the bit N5 is used to indicate whether or not the multiframe number is used. In this way, since the data used for the multi-frame number is 4 bits, the multi-frame number changes in descending order with a value of 0 to 15, and the same multi-frame number appears every 16 multi-frames.

The tenth frame, the twelfth frame,
And bit L of the 1st octet of the 13th frame
1, L2, L3 are used to display the connection number indicating the order in which the B channels carrying the frame among the currently used B channels are connected. Also, the bit R of the first octet of the fifteenth frame is reserved (reserved) for future recommendation,
The value is set to 0.

The bit TEA of the first octet of the 14th frame is used to indicate that data transmission is not possible due to an internal failure of the data terminal device.

Also, odd-numbered frames FLM1, FLM3
.., bit A of the third octet of the FLM 15 is used to indicate whether frame synchronization or multi-frame synchronization is established or out of synchronization.

Also, odd-numbered frames FLM1, FLM3
..., bit C1 of the fifth octet, sixth octet, seventh octet, and eighth octet of FLM15
C2, C3 and C4 are for displaying a CRC (Cyclic Redundancy Check) code that is referred to for data error detection (that is, channel quality detection) of two consecutive frames (that is, sub-multiframe). , And the bit E of the fourth octet of the odd frames FLM1, FLM3, ..., FM15 is used to indicate that a transmission error has been detected on the receiving side.

The bit rate allocation signal BAS is, as shown in FIG. 7, even-numbered frames FLM0, FLM2,
.., FLM14, 8-bit data representing the capability BAS or BAS command is arranged, and in the subsequent odd numbered frames FLM1, FLM3 ,.
A double error correction code for error correcting the value of the capability BAS or BAS command transmitted in the immediately preceding frame is arranged.

Further, the transmission of the data of the multi-frame MFL is performed in the order of frame numbers, and the respective frames FLM0 to FLM15 are transmitted in the order of octets from the 1st octet to the 80th octet, as shown in FIG. The first bit of the octet is sent first.

That is, each of the frames FLM0 to FLM0
In the FLM 15, the first bit of the first octet is transmitted first and the eighth bit of the 80th octet is transmitted last.

FIG. 9 shows the TTC standard JT-H.264 applied as a transmission control procedure executed by an audiovisual terminal such as a communication conference terminal when transmitting data using the B channel. 242 shows an example of a general procedure of 242. In this case, an example of a transmission procedure for exchanging audio data, general-purpose data, and moving image data between terminals using two B channels is shown.

First, the calling terminal makes a call to the destination terminal and performs a call setup procedure on the D channel to secure one B channel (hereinafter referred to as the first channel) (Phase A), Frame synchronization is performed while exchanging frame data in which PCM voice data (A-law or μ-law, 64 Kbps) is set on one channel (frame mode), and when frame synchronization is established, mutual capability BAS
Data and command BAS data are exchanged (phase B1-1), the transmission mode to be used at that time is determined, and an additional call setup request for securing the second B channel is started (phase B1-2). ).

Then, in principle, the modes having the highest functions common to each other are selected from the contents of the exchange of the transmission modes at that time (phase B1-3), and the calling terminal receives the selected operation mode. Send a BAS command that specifies the terminal function to operate the function to the calling terminal,
Parameters common to the device functions of the calling terminal and the called terminal are set (phase B2). Thereby, in the first channel, for example, data transmission of audio data (16 Kbps) and data transmission of moving image data (46.4 Kbps) corresponding to the transmission mode selected at that time are performed (phase C). .

When the first channel starts data transmission in the frame mode, the call setup procedure is performed on the D channel for the second B channel (hereinafter referred to as the second channel) (phase CA), and the second channel is established. Then, frame data including only the frame synchronization signal FAS and the bit allocation signal BAS is exchanged using the second channel to establish frame synchronization and multi-frame synchronization (phase CB1-11), and then the first channel and the second channel. Synchronization between channels is established (phase CB1-12).

When the synchronization of the two B channels is completed, the BAS command is sent from the calling terminal side to set the transmission mode (phase CB1-2), and the transmission mode is switched to the set contents (phase CB1-3). ), Common parameters are set (phase CB3).

In this way, when the initialization of the second channel is completed, after that, the frame data exchanged on the first channel and the frame data exchanged on the second channel are synchronized with each other. Using the B channel, for example, voice data, general data, and
Video data is 58 Kbps and 6.4 Kbps, respectively
And a data rate of 62.4 Kbps is assigned for data transmission (see FIG. 10). Here, the general-purpose data channel exchanges C & I mode (conference control function) data other than voice data, for example, C & I function, telewriting communication function, and bulk transfer function (group 4 facsimile data, etc.) data. Used for.

To end such data transmission, first disconnect from the second channel. At this time, the first
For voice data transmission on the channel only, the procedure for setting the common mode is performed (Phase CD
1), the mode of the second channel is switched to the mode 0F of the frame mode (phase CD2). At this time, the first channel and the second channel are asynchronous, and the second channel is in a state in which the call is held in the transmission state of only the frame synchronization signal FAS and the bit allocation signal BAS, and the call of the D channel is disconnected. The call for the second channel can be released by the release procedure.

In the first channel, phase CD1
During the phase CD2, the audio data and the moving image data are transmitted at the total transmission rate of 62.4 Kbps in the frame mode. Further, when the operator of one terminal ends the call, the transmission of the moving image data is finished. In order to use all the transmission capacities of the first channel including the transmission capacity of the moving image data for voice transmission, the mode is switched to the mode 0F (phase D2), and then the call disconnection release procedure of the D channel is performed. Is ready to be released.

As a result, the call disconnection release procedure is executed on the D channel for the first channel and the second channel (phase E), and the audiovisual transmission between the two terminals is completed.

As described above, in an audiovisual terminal such as a video conference communication terminal device, one B channel (first channel) is first secured and a frame mode is established, and then audio data and a moving image are transmitted on this first channel. If the second B channel (second channel) can be set at the same time while assigning the data transmission rate and performing the data transmission in the transient mode, the second channel is set by the D channel call setup procedure. Secure. Then, the first channel transmitting in the transient mode and the newly secured second channel are channel-synchronized, and when the channel synchronization is established, the allocation of the transmission rate of the audio data and the moving image data is reset. However, in order to utilize the increased transmission capacity of the B channel, the coding rule (coding method) of audio data and moving image data is changed so that higher quality audio data and moving image data can be exchanged. There is.

Further, when the data transmission is finished, it is necessary to once change from the mode in which the transmission path in which both the first channel and the second channel are synchronized is used to the mode in which only the first channel is used. is there. Therefore, first, each encoding rule of audio data and moving image data is set to a method that optimizes the transmission capacity of the first channel of 62.4 Kbps, and the transmission mode of only the first channel is changed, while the second channel is , The state of synchronization with the first channel is stopped, the mode shifts to mode 0F in which user data is in an idle transmission state, and the call is disconnected / released by the call disconnection release procedure of the D channel. The first channel is
From two types of media transmission of audio data and video data,
After changing to mode 0F, which is a transmission mode for only voice data, the call is disconnected / released by the D channel call disconnection release procedure.
release. In addition, the first channel, without switching the mode to two types of media transmission of audio data and video data,
It is also possible to disconnect / release the call after directly changing the mode to the mode 0F. In addition, the billing information obtained in the call disconnection / release procedure is managed for each channel.

With the above configuration, when the conference session is being executed with the partner terminal, as described above, the audio signals SA1, SA2 of the microphones 2, 3, 4 installed in front of the main speaker. , SA3 is amplified with the largest gain, so that the received voice obtained at the partner terminal contains almost no voice other than that of the main speaker, so that the partner terminal can clearly hear the voice of the main speaker. You can

In this state, as shown in FIG. 11, in the small area at the lower right of the display screen of the operation display device 8, an operation symbol SB1 for adjusting the volume of the voice transmitted to the partner terminal, An operation symbol SB2 for adjusting the frequency characteristic of the transmission voice is displayed. The operation symbols SB1 and SB2 may be displayed only when the user makes a display request.

In this case, for example, by touching the thick vertical line bar at the center of the operation symbol SB1 with the pen 9 and moving to the left or right while maintaining the touched state, the display position of the bar can be changed. , If you move the display position of the bar to the left, you can reduce the volume of the transmitted voice,
Further, the volume of the transmitted voice can be increased by moving the display position of the bar to the right.

Similarly, if the bar of the operation symbol SB2 is touched with the pen 9 and the bar is moved further to the left, the frequency band of the transmitted voice changes to a lower frequency band, and if the bar is moved further to the right, the transmitted voice is changed. Changes to a higher frequency band.

FIG. 12 shows an example of processing when adjusting the volume.

First, the system control unit 11 monitors that the operation symbol SB1 is touch-operated and the volume adjustment command is issued (NO loop of judgment 101), and the operation symbol SB1 is touch-operated and judgment 101 is made. The result is YE
When S, the touch operation is maintained and it is monitored whether the touch coordinates have changed (decision 10).
2).

When the user touches the operation symbol SB1 and operates to move the bar, and the result of the determination 102 is YES, the volume corresponding to the coordinates after the movement is calculated, and the volume corresponding to the volume is calculated. Gain control signal SC1
Is set (process 103), the display position of the bar of the operation symbol SB1 is updated to the position corresponding to the coordinate after movement (process 104), and the process returns to the determination 101.

Therefore, the user operates the operation symbol SB1.
When you touch the bar to move the bar a small amount to move it left or right, the volume of the transmitted voice is set to the volume corresponding to the coordinates of the move destination, and the bar is displayed at the move destination. To be done.

Therefore, the user can control the magnitude of the audio signal transmitted to the partner terminal to a desired volume by operating the bar left and right while confirming the position of the bar of the operation symbol SB1.

FIG. 13 shows an example of processing at the time of frequency characteristic adjustment.

First, the system control section 11 monitors that the operation symbol SB2 is touch-operated and the frequency characteristic adjustment is commanded (NO loop of judgment 201), and the operation symbol SB2 is touch-operated and judgment 201 is performed. If the result is YES, it is monitored whether the touch coordinates have changed while the touch operation is held (decision 202).

When the user touches the operation symbol SB2 and operates to move the bar, and the result of the determination 202 is YES, the volume corresponding to the coordinates after the movement is calculated, and the volume corresponding to the volume is calculated. Characteristic control signal SC2
A value is set (process 203), the display position of the bar of the operation symbol SB2 is updated to the position corresponding to the coordinate after movement (process 204), and the process returns to the determination 201.

Therefore, the user operates the operation symbol SB2.
When the bar is touch-operated and the bar is moved to the left or right by a small amount, the frequency characteristic characteristic of the transmission voice is set to the characteristic corresponding to the coordinates of the movement destination.
A bar is displayed at the destination.

Therefore, the user operates the bar left and right while confirming the position of the bar of the operation symbol SB2, so that the sound quality (frequency characteristic) of the audio signal to be transmitted to the partner terminal.
Can be controlled in a desired manner.

In this way, in this embodiment, the voice of the main speaker can be transmitted to the partner terminal while being emphasized, so that the partner terminal can clearly hear the voice of the main speaker. .

Further, since the volume and frequency characteristic (sound quality) of the transmitted voice can be adjusted appropriately, the voice can be adjusted in a manner desired by the partner terminal.

FIG. 14 is a block diagram of the voice input / output device 18.
7 shows another example of a circuit that processes audio signals from the microphones 2, 3, and 4. In the figure, the same parts as those in FIG. 3 and corresponding parts are designated by the same reference numerals.

Audio signal SA1 output from the microphone 2
Is added to the volume controller 40 and the variable gain amplifier 32, and the audio signal SA2 output from the microphone 3 is added to the volume controller 40 and the variable gain amplifier 35, and the audio signal SA3 output from the microphone 4 is It is added to the volume controller 40 and the variable gain amplifier 37.

The variable gain amplifier 32 amplifies the audio signal SA1 with a gain corresponding to the value of the gain control signal SS1 applied from the volume controller 40, and its output signal S1.
A1a is added to the polarity setting device 41.

The variable gain amplifier 35 amplifies the audio signal SA2 with a gain corresponding to the value of the gain control signal SS2 applied from the volume control section 40, and its output signal S2.
A2a is added to the polarity setter 42.

The variable gain amplifier 37 amplifies the audio signal SA3 with a gain corresponding to the value of the gain control signal SS3 added from the volume control section 40, and its output signal S3.
A3a is added to the polarity setter 43.

The polarity setter 41 outputs the input signal SA1a as it is as the signal SA1b when the polarity setting signal SD1 applied from the volume controller 40 is set to a positive polarity, and Polarity setting signal SD1
Is set to a negative polarity, the input signal S
A signal obtained by converting A1a into a negative value is output as a signal SA1b, and the output signal SA1b is added by the adder 3
3 to one input terminal.

The polarity setter 42 outputs the input signal SA2a as it is as the signal SA2b when the polarity setting signal SD2 applied from the volume controller 40 is set to a positive polarity, and Polarity setting signal SD2
If it is set to negative polarity, the input signal SA
A signal obtained by converting 2a into a negative value is output as a signal SA2b. The output signal SA2b is added by the adder 33.
Has been added to one input end of.

The polarity setting device 43 outputs the input signal SA3a as it is as the signal SA3b when the polarity setting signal SD3 applied from the volume controller 40 is set to a positive polarity, and Polarity setting signal SD3
Is set to a negative polarity, the input signal S
A signal obtained by converting A3a into a negative value is output as a signal SA3b, and the output signal SA3b is output by the adder 3
3 to one input terminal.

The adder 33 adds the signal SA1b,
SA2b and SA3b are added together, and the output signal thereof is added to the variable gain amplifier 38.

The volume control section 40 controls the audio signals SA1 and SA.
Of SA2 and SA3, the signal with the highest audio level is determined. Then, the gain control signal S corresponding to the maximum signal
S1, SS2, SS3 are set to a predetermined main voice gain value Gm, and gain control signals SS1, S corresponding to other signals are set.
S2 and SS3 are set to a predetermined non-main voice gain value Gn (<Gm). Further, the polarity setting signals SD1, SD2, SD3 corresponding to the maximum signal are set to values corresponding to the positive polarity, and the polarity setting signals SD corresponding to other signals are set.
Set 1, SD2 and SD3 to values corresponding to negative polarity.

Therefore, for example, when a member who is seated immediately before the microphone 2 speaks, the audio signal SA1
Is determined as the maximum level, the gain control signal SS1 is set to the main audio gain value Gm, and the gain control signal S
S1 and SS2 are set to the non-main audio gain value Gn, the polarity setting signal SD1 is set to a value corresponding to the positive polarity, and the polarity setting signals SD2 and SD3 are set to the value corresponding to the negative polarity.

As a result, the operation of the adder 33 at this time is as in the following equation.

Y = SA1 × Gm− (SA2 + SA3) × Gn

Here, the voice signal SA1 output from the microphone 2 is dominated by the voice of the main speaker (hereinafter referred to as the main voice) and the voices of other members (hereinafter referred to as the non-main voice). Hardly included. On the other hand, in the audio signals SA2 and SA3 output from the microphones 3 and 4,
Main voice and non-main voice are included to some extent.

Therefore, by subtracting the value obtained by adding the audio signals SA2 and SA3 from the audio signal SA1, the non-main audio included in the audio signal SA1 can be removed. However, in this case, since the audio signals SA2 and SA3 also include the main audio component, the main audio is slightly attenuated from the audio signal SA1, and the level of the output signal of the adder 33 is reduced as a whole. By setting the gain value Gm and the non-main voice gain value Gn to appropriate values, and setting the gain of the variable gain amplifier 38 to an appropriate value, the level of the voice signal transmitted to the partner terminal is set to a desired value. can do.

[0107]

As described above, according to the present invention,
Of the voice signals input from a plurality of microphones, the gain of the variable gain amplifier that amplifies the voice signal higher than a predetermined level is set to a large value, so that the voice signal of the main speaker can be emphasized, and the other terminal Then, the voice of the main speaker can be clearly heard. Further, since the signal in the non-voice band included in the signal input from the microphone is removed, it is possible to obtain the effect that the other terminal can obtain clear voice in which noise other than voice is suppressed.

Further, since the frequency characteristic and the volume of the voice signal sent to the partner terminal can be adjusted appropriately, the partner terminal can obtain a better quality voice.

Further, among the voice signals input from the plurality of microphones, voice signals other than the voice signal caused by the utterance of the main speaker can be removed to some extent.
This also has the effect of clearly hearing the statement of the main speaker.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a communication conference terminal device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an example of the configuration of a main body device.

FIG. 3 is a block diagram showing an example of a circuit that processes an audio signal from a microphone in the audio input / output device.

FIG. 4 is a schematic diagram showing an example of a frame configuration of multi-frame.

FIG. 5 is a schematic diagram showing an example of a signal configuration of one frame.

FIG. 6 is a schematic diagram showing an example of a frame adjustment signal.

FIG. 7 is a schematic diagram showing an example of a bit allocation signal.

FIG. 8 is a schematic diagram for explaining a signal transmission order.

FIG. 9: TTC Recommendation JT-H. The time chart which showed the example of the general procedure of 242.

FIG. 10 is a schematic diagram showing an example of allocation of transmission capacities to audio data, general-purpose data, and moving image data in data transmission using two B channels.

FIG. 11 is a schematic diagram showing an example of operation symbols for volume adjustment and frequency characteristic adjustment.

FIG. 12 is a flowchart showing a processing example at the time of adjusting the volume.

FIG. 13 is a flowchart showing a processing example at the time of frequency characteristic adjustment.

FIG. 14 is a block diagram showing another example of a circuit that processes an audio signal from a microphone in the audio input / output device.

[Explanation of symbols]

 1 Main Unit 2, 3, 4 Microphone 11 System Control Unit 12 ROM (Read Only Memory) 13 RAM (Random Access Memory) 18 Voice Input / Output Device 31, 34, 36 Voice Level Judgment Unit 32, 35, 37 , 38 Variable gain amplifier 33 Adder 39 Low-pass filter 40 Volume controller

Claims (9)

[Claims] 1. At least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function are provided.
In a communication conference terminal device that transmits voice signals input from a plurality of microphones to a partner terminal, it is determined that a plurality of voice signals input from a plurality of microphones are higher than a predetermined level, respectively. Means for amplifying a plurality of audio signals respectively inputted from a plurality of microphones, and when it is determined that the corresponding audio level determination means of the plurality of audio level determination means is higher than a predetermined level, the first And a plurality of variable gain amplifiers for which the second gain is set when it is determined that the corresponding audio level determination means among the plurality of audio level determination means is below a predetermined level. , An adder for adding the output signals of the plurality of variable gain amplifiers, and the output signal of the adder as a transmission voice signal to the other terminal A communication conference terminal device, comprising: a control means for transmitting to the communication conference terminal device. 2. At least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function,
In a teleconference terminal device that transmits audio signals input from multiple microphones to a partner terminal, an adder that adds multiple audio signals input from multiple microphones, and a predetermined audio band from the output signal of the adder A communication conference terminal device comprising: low-pass filter means for extracting a signal; and control means for transmitting the output signal of the low-pass filter means to a partner terminal as a transmission voice signal. 3. At least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function,
In a communication conference terminal device that transmits voice signals input from a plurality of microphones to a partner terminal, it is determined that a plurality of voice signals input from a plurality of microphones are higher than a predetermined level, respectively. Means for amplifying a plurality of audio signals respectively inputted from a plurality of microphones, and when it is determined that the corresponding audio level determination means of the plurality of audio level determination means is higher than a predetermined level, the first And a plurality of variable gain amplifiers for which the second gain is set when it is determined that the corresponding audio level determination means among the plurality of audio level determination means is below a predetermined level. , An adder for adding the output signals of the plurality of variable gain amplifiers, and a signal in a predetermined audio band is extracted from the output signals of the adder. A communication conference terminal device comprising: a low-pass filter means for outputting and a control means for transmitting an output signal of the low-pass filter means as a transmission voice signal to a partner terminal. 4. At least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function are provided,
In a communication conference terminal device that transmits voice signals input from a plurality of microphones to a partner terminal, it is determined that a plurality of voice signals input from a plurality of microphones are higher than a predetermined level, respectively. Means for amplifying a plurality of audio signals respectively inputted from a plurality of microphones, and when it is determined that the corresponding audio level determination means of the plurality of audio level determination means is higher than a predetermined level, the first And a plurality of variable gain amplifiers for which the second gain is set when it is determined that the corresponding audio level determination means among the plurality of audio level determination means is below a predetermined level. , An adder for adding the output signals of the plurality of variable gain amplifiers, and a signal in a predetermined audio band is extracted from the output signals of the adder. And a control means for transmitting the output signal of the low-pass filter means to the other terminal as a transmission voice signal and adjusting the frequency characteristic of the low-pass filter means by a command. A communication conference terminal device characterized by the above. 5. A communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function are provided at least,
In a communication conference terminal device that transmits voice signals input from a plurality of microphones to a partner terminal, it is determined that a plurality of voice signals input from a plurality of microphones are higher than a predetermined level, respectively. Means for amplifying a plurality of audio signals respectively inputted from a plurality of microphones, and when it is determined that the corresponding audio level determination means of the plurality of audio level determination means is higher than a predetermined level, the first And a plurality of variable gain amplifiers for which the second gain is set when it is determined that the corresponding audio level determination means among the plurality of audio level determination means is below a predetermined level. , An adder for adding the output signals of the plurality of variable gain amplifiers, and a signal in a predetermined audio band is extracted from the output signals of the adder. A communication conference terminal comprising: a low-pass filter means for outputting and a control means for transmitting the output signal of the low-pass filter means to a partner terminal as a transmission voice signal and adjusting the output gain of the adder by a command. apparatus. 6. At least a communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function are provided,
In a communication conference terminal device that transmits voice signals input from a plurality of microphones to a partner terminal, it is determined that a plurality of voice signals input from a plurality of microphones are higher than a predetermined level, respectively. Means for amplifying a plurality of audio signals respectively inputted from a plurality of microphones, and when it is determined that the corresponding audio level determination means of the plurality of audio level determination means is higher than a predetermined level, the first And a plurality of variable gain amplifiers for which the second gain is set when it is determined that the corresponding audio level determination means among the plurality of audio level determination means is below a predetermined level. , An adder for adding the output signals of the plurality of variable gain amplifiers, and a signal in a predetermined audio band is extracted from the output signals of the adder. Along with the output, the low-pass filter means capable of changing the frequency characteristic, and the output signal of the low-pass filter means is transmitted to the other terminal as a transmission voice signal, and the frequency characteristic of the low-pass filter means by a command, and the adder A communication conference terminal device comprising control means for adjusting an output gain. 7. The first gain is set to a value larger than the second gain, claim 1, claim 3, claim 4, claim 5, or claim 7. Item 6
The described communication conference terminal device. 8. A communication conference terminal function, a voice transmission / reception function, and a moving image transmission / reception function are provided at least,
In a communication conference terminal device that transmits a voice signal input from a plurality of microphones to a partner terminal, a largest voice signal is determined from a plurality of voice signals respectively input from the plurality of microphones, and the first voice signal is set as the voice signal.
A voice signal calculating means for multiplying the voice signal other than the above by the second coefficient, and subtracting the sum of the voice signals multiplied by the second coefficient from the voice signal multiplied by the first coefficient. A low-pass filter means for extracting a signal in a predetermined voice band from the output signal of the voice signal calculation means, and a control means for transmitting the output signal of the low-pass filter means to a partner terminal as a transmission voice signal, Teleconference terminal device for 9. At least a communication conference terminal function, a voice transmitting / receiving function, and a moving image transmitting / receiving function are provided, and
In a communication conference terminal device that transmits a voice signal input from a plurality of microphones to a partner terminal, a largest voice signal is determined from a plurality of voice signals respectively input from the plurality of microphones, and the first voice signal is set as the voice signal.
A voice signal calculating means for multiplying the voice signal other than the above by the second coefficient, and subtracting the sum of the voice signals multiplied by the second coefficient from the voice signal multiplied by the first coefficient. A low-pass filter means capable of extracting a signal in a predetermined voice band from the output signal of the voice signal computing means and changing its frequency characteristic, and transmitting the output signal of the low-pass filter means to a partner terminal as a transmission voice signal. A communication conference terminal device comprising: a control unit that adjusts a frequency characteristic of the low-pass filter unit and an output gain of the audio signal calculation unit according to a command.