JPS6038065B2 - conference phone equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a conference telephone system used between distant conference rooms, and more particularly to a system for automatically controlling the relative volume of a plurality of speakers on a receiving side using a control signal transmitted from a transmitting side.

In conventional conference telephone devices, outgoing audio signals collected by multiple microphones are simply mixed and transmitted, and multiple speakers are simultaneously amplified at a fixed audio output level on the receiving side.

In such a method, since the reproduced sound is uniform, it is not possible to determine the location (sense of direction) of the other conference participants in the room, and it is not possible to obtain a sense of realism as in a conference held in the same conference room.

Specifically, assuming that a conference is held in the same conference room, the speaker's voice will be loud to people who are close to the speaker, and quiet to people who are further away from the speaker. This allows meeting participants to:
The direction (position) of the speaker can be known, allowing for a realistic meeting. This kind of sense of direction is even more necessary in conference rooms that are far apart, where you cannot see the faces of the speakers. The present invention makes it possible to assume the indoor placement of speakers (sound sources) between conference rooms that are far apart (sense of direction), and to easily and economically create a sense of presence as if the conference were in progress in the same room. The present invention provides a conference telephone device that can be obtained. The present invention detects speech voice levels individually or for each group, creates a control signal based on the detection signal, frequency division multiplexes the signal with the voice signal, and transmits the signal.

By detecting (separating) the control signal superimposed on the audio signal on the receiving side and individually controlling the audio signal playback volume of the corresponding speakers for each group using the control signal,
The aim is to create a sense of realism in meetings that are held in separate conference rooms as if they were being held in the same conference room. Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows the main blocks of the transmitter side. Further, FIG. 2 shows a main block diagram of the receiving side. However, the sending side also has a second
The circuit shown in the figure and the circuit shown in Fig. 1 are also included on the receiving side, and both the transmitting and receiving sides constitute the same conference telephone device, but the circuits in Figs. 1 and 2 are connected by one line. In this embodiment, for convenience, one of the conference telephone devices is referred to as the transmitting side and the other as the receiving side. Microphone 1-1, 1-2, 1-
The speech sounds picked up by the microphones are connected to an audio mixing and amplification circuit 2, and the speech sounds picked up by the respective microphones are mixed and amplified and then connected to a microwave circuit 3. In the furnace wave circuit, a part of the audio frequency band is sharply removed and connected to the control signal addition circuit 4. On the other hand, the microphone output is also connected to the audio level detection circuit 6, which individually detects the microphone that received audio input from among the plurality of microphones, and sends the audio level signal for each microphone to the control signal generation circuit 7, for example, as "1".
, is sent as a “0” signal. The control signal generation circuit is
a corresponding signal generating section 7 that generates a signal that increases the output audio level of a speaker on the receiving side (FIG. 2) located relative to the microphone receiving the audio input based on the audio level signal; It includes a signal conversion section 72 that converts the generated signal into a predetermined signal and generates it as a control signal, and is connected to a control signal addition circuit. In the control signal addition circuit, the control signal is added to the audio frequency band whose wave has been removed by the tear wave circuit 3, and is connected to the transmission output terminal 8 via the transmission amplifier circuit 5. FIG. 2 shows the main blocks on the receiving side.

A reception input signal at the reception input terminal 9 is connected to a furnace wave circuit 11 via a reception amplifier circuit 10 . The control signal superimposed on the audio signal is removed by the oven wave circuit 11, and only the audio signal is connected to the speaker amplifier circuits 12--, 12-2, 12-n. On the other hand, the output of the reception amplifier circuit 10 is
is also connected to. The audio signal is removed in the microwave circuit 13 and only the control signal is connected to the control signal demodulation circuit 14.
The control signal is converted into a signal corresponding to the audio level on the transmitting side in a control signal demodulation circuit, and controls the output level of the speaker amplifier circuit. Therefore, for example, when there is an audio input to the microphone 1-1 on the transmitting side, on the receiving side, the speaker located relative to the microphone 1-1, such as the speaker 15-1 or the speaker 15-1,
, 15-2 can be increased. It is also possible to increase the volume of the speaker 15-1 in response to audio input from the microphones 1-1 and 1-2. Furthermore, it is also possible to lower the volume of the speaker on the receiving side in response to the audio input from the microphone on the transmitting side.
As described above, the speakers 16-1, 15-2, 15-
The reproduction output of n is controlled in accordance with the speaker group on the transmitting side, and it is possible to reproduce a sound field in which the direction of the speaker on the other party (transmitting side) can be easily assumed. As explained above, the present invention allows the indoor layout of the speaker side conference room to be easily assumed by controlling the playback volume of the speakers arranged corresponding to the speaker group using the speech audio signal. This has the effect of providing a sense of presence similar to that of a meeting in the same room.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the main parts of the transmitting side of the conference telephone apparatus according to the present invention, and FIG. 2 is a block diagram of the receiving side. 1-1, 1-2, 1-n""" microphone, 2...
...Audio mixing amplification circuit, 3...Reason wave circuit, 4
... Control signal addition circuit, 5 ... Transmission amplifier circuit, 6 ... Audio level detection circuit, 7 ... Control signal creation circuit, 8 ... Transmission Output terminal, 9...
... Reception input terminal, 10 ... Reception amplifier circuit, 11 ... Reactor wave circuit, 12-1, 12-2, 1
2-n... Speaker amplification circuit, 13... Rear wave circuit, 14... Control signal demodulation circuit, 15-1, 15-
2,15-n...Speech ability. Rare scale scale Z diagram

Claims (1)

[Claims] 1. In a conference telephone device that includes a microphone and a speaker, and transmits an audio signal from the microphone to a line, and outputs an audio signal from the line from the speaker to make a call between distant conference rooms. , an audio level detection circuit that individually detects the level of the audio signal of the microphone and generates an audio level signal for each microphone; a control signal generation circuit that generates a control signal corresponding to the audio level signal; and the microphone. Frequency division multiplexing means for frequency division multiplexing the control signal on an audio signal from the network and transmitting the control signal to a line; means for separating the audio signal and the control signal from a signal received from the line; and a separated audio signal. and speaker amplification means for transmitting an audio signal having an output level corresponding to the control signal to each speaker.