JPH0731654Y2 - Television telephone equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a video telephone device.

[Outline of device]

According to the present invention, a video signal from an image pickup means and an audio signal from a transmitter are transmitted as a transmission signal through an encoding circuit and a multiplexing synthesis circuit, respectively, and a reception signal is supplied to a demultiplexing circuit and a decoding circuit. In a television telephone device in which a video signal and an audio signal are respectively supplied to a receiver and a receiver, a switch circuit for switching a reception signal and a transmission signal to a demultiplexing circuit and a decoding circuit are supplied to the receiver. The video signal of the video signal to be transmitted is provided by providing a mute circuit for muting the audio signal to be transmitted and a controller for switching the mute circuit to the mute state when the transmission signal is supplied to the demultiplexing circuit through the switch circuit. Check with your own receiver to see if there is any abnormality in each circuit of the transmission / reception system including the multiplexing / combining circuit and demultiplexing circuit. It is possible to perform easily, is obtained so as to eliminate Kikigurushi of speech due to the echo effect by delaying the audio signal to be transmitted at the same time as the video signal to be its transmission.

[Conventional technology]

Conventionally, a video signal obtained by transmitting a video signal from a television camera and an audio signal from a transmitter through an encoding circuit and a multiplexing synthesis circuit, respectively, and supplying a received signal to a demultiplexing circuit and a decoding circuit. Also, there has been proposed a television telephone device in which audio signals are supplied to a receiver and a receiver, respectively.

[Problems to be solved by the invention]

In such a conventional television telephone device, during a call, it is possible to confirm how the face of the user is reflected on the receiver of the other television telephone device, and there is no abnormality in the circuits of the transmission system and the reception system. In order to check whether or not the video signal and the audio signal obtained by demultiplexing and decoding the transmission signal are self-monitored by the receiver and the receiver of the own television telephone device.

By the way, generally, in a telephone device, the voice signal from the transmitter is directly supplied to the receiver so that the user's voice can be heard together with the other party's voice while making a call. Is normal.

Therefore, when an audio signal obtained by demultiplexing and decoding the transmission signal is supplied to the receiver of the own television telephone device, the transmission signal is encoded circuit, multiplexing synthesis circuit, demultiplexing circuit and decoding circuit. Is converted to a voice signal through and reaches the handset for a certain amount of time, for example 10
It takes 0 to 200 msec. Therefore, the voice signal directly from the transmitter and the voice signal delayed by a predetermined time from this are supplied to the handset, so that the person making the call can use his or her own voice during self-monitoring. Will be heard by echo, and it will be very difficult to hear.

According to the present invention, a video signal from an image pickup means and an audio signal from a transmitter are transmitted as a transmission signal through an encoding circuit and a multiplexing synthesis circuit, respectively, and a reception signal is supplied to a demultiplexing circuit and a decoding circuit. In a television telephone device in which a video signal and an audio signal are respectively supplied to a receiver and a receiver, the image of the video signal to be transmitted is confirmed by its own receiver, and thereby the multiplexing and combining circuit and the multiplexing and demultiplexing are performed. It is possible to easily check whether or not there is any abnormality in each circuit of the transmission / reception system including the circuit, and it is difficult to hear the sound due to the echo effect due to the delay of the audio signal to be transmitted at the same time as the video signal to be transmitted. The idea is to propose something that can eliminate the problem.

[Means for solving problems]

According to the present invention, a video signal from an image pickup means (4) and an audio signal from a transmitter (2) are encoded circuits (7) and (9), respectively.
And a video signal and an audio signal, which are transmitted as a transmission signal through the multiplexing and synthesis circuit (10) and supplied to the demultiplexing circuit (11) and the decoding circuits (12) and (14), respectively. In a television telephone device adapted to be supplied to a machine (5) and a receiver (3), a switch circuit (16) for switching and supplying a received signal and a transmitted signal to a demultiplexing circuit (11) and a decoding circuit (14) ), A mute circuit (17) for muting the audio signal supplied to the handset (3),
When the transmission signal is supplied to the demultiplexing circuit (11) through the switch circuit (16), a controller (19) for switching the mute circuit (17) to the mute state is provided.

[Action]

According to the present invention, the transmission signal is transmitted to the switch circuit (16).
When it is supplied to the demultiplexing circuit (11) through the, the video of the video signal to be transmitted is confirmed by the own receiver (5),
As a result, it is confirmed whether or not each circuit of the transmission / reception system including the multiplexing / combining circuit (10) and the multiplexing / demultiplexing circuit (11) has any abnormality. At this time, the mute circuit (17) prevents the voice signal to be transmitted from being supplied to the handset (3), and only the voice signal supplied from the handset (2) to the handset (3) immediately is received by the handset ( Since it is reproduced from 3), there is no difficulty in listening due to the echo effect of own voice.

〔Example〕

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the figure, (1) is a handset, and (2) and (3) are its transmitter and receiver, respectively. (4) is a television camera as an image pickup means, and (5) is a receiver.

First, the transmission system S will be described. The video signal transmitted from the camera (4) is supplied to the A / D converter (6) and converted into a digital video signal, and then a video high efficiency encoding circuit (7)
Is supplied to and encoded. In addition, the transmission voice signal from the transmitter (2) of the handset (1) is supplied to the A / D converter (8) and converted into a digital voice signal, which is then transmitted to the voice efficient coding circuit (9). Supplied and encoded. Then, the encoded video signal from the video high efficiency encoding circuit (7) and the encoded audio signal from the audio high efficiency encoding circuit (9) are supplied to the multiplexing synthesis circuit (10) to perform time division multiplexing. The combined transmission signal obtained has a transmission rate of, for example, 64 kb / s.
It is transmitted to the other party's television telephone device via the telephone line (not shown) of ec and the exchange.

Next, the receiving system R will be described. The signal received from the telephone line is supplied to a demultiplexing circuit (11), time-division multiplexed and demultiplexed into a digital video signal and a digital audio signal,
They are supplied to a video high efficiency decoding circuit (12) and an audio high efficiency decoding circuit (14), respectively. Video high efficiency decoding circuit (12)
And the digital video signal and the digital audio signal from the audio high efficiency decoding circuit (14) are respectively D / A converters (13) and (1
After being supplied to 5) and converted into analog video signals and analog audio signals respectively, they are supplied to the receiver (5) and the handset (3) of the handset (1), respectively. The above is the same configuration as the conventional television telephone device.

Hereinafter, a configuration different from that of the conventional television telephone device will be described. Demultiplexing circuit for transmitting and receiving signals (1
A switch circuit (16) for switching and supplying to 1) is provided. Further, a mute circuit (17) is provided between the D / A converter (15) and the handset (3). A turn-on / off selection switch (lock switch or non-lock normally open switch) (18) is provided, and a mute controller (19) and a switch controller (20) controlled by turning on / off the switch (18). ) Is provided and the mute circuit (17) and the switch circuit (16) are controlled by the controllers (19) and (20) thereof.

The operation of the video telephone apparatus of this embodiment will be described below. When making a call, switch (1
8) is operated to control the switch circuit (16) and the mute circuit (17) so that the transmission signal from the multiplexing and combining circuit (10) is supplied to the demultiplexing circuit (11) and the mute circuit is also supplied. Allow (17) to switch to the mute state. In this way, the transmission signal is supplied to the demultiplexing circuit (11) through the switch circuit (16) for time division demultiplexing, and further supplied to the high efficiency decoding circuits (12) and (14) to be digitalized respectively. The signals are decoded into video signals and digital audio signals, and then supplied to D / A converters (13) and (15) to be converted into analog video signals and analog audio signals. The internal video signal is supplied to the receiver (5) to reproduce the video, but the audio signal is muted by the mute circuit (17) and is not supplied to the handset (3) and is transmitted by the handset (1). The voice signal from the handset (2) is only supplied directly to the handset (3). Thus, the person who made the call determines whether or not the subject such as his or her face is displayed at an appropriate position on the screen of the receiver (5), and the encoding circuits (7), (9) and the multiplex composition. It can be confirmed whether the circuit (10), the demultiplexing circuit (11) and the decoding circuits (12) and (14) are operating normally. Further, the content of the caller talking to the transmitter (2) can be monitored without echo by only supplying a voice signal directly from the transmitter (2) to the receiver (3). it can.

When the above confirmation operation is completed, the switch (18) is operated so that the received signal is supplied to the demultiplexing circuit (11) through the switch circuit (16) and the mute circuit (17) is set to the non-mute state. The transmission signal is transmitted only to the telephone line, and the reception signal from the telephone line is supplied to and received by the demultiplexing circuit (11).

The self-monitoring may be automatically performed by detecting that the handset (1) is picked up when making a call, without manually operating the switch (18).

[Effect of device]

According to the present invention described above, the image of the image signal to be transmitted is confirmed by its own receiver, and it is confirmed whether or not there is any abnormality in each circuit of the transmission / reception system including the multiplexing / synthesizing circuit and the demultiplexing circuit. In addition, it is possible to eliminate the difficulty of listening to the sound due to the echo effect due to the delay of the audio signal to be transmitted simultaneously with the video signal to be transmitted.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention. (1) is a handset, (2) is a transmitter, (3) is a receiver, (4) is a camera, (5) is a receiver, (6) and (8) are
A / D converters, (7) and (9) are video and audio high efficiency encoding circuits, (10) is a multiplexing synthesis circuit, (11) is a demultiplexing circuit, and (12) and (14) are High-efficiency video / audio decoding circuits, (13) and (15) are D / A converters, (16) is a switch circuit, and (17) is a mute circuit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Ikuoka Ikuoka, Aki Izumioka 1-2356 Take, Yokosuka City, Kanagawa Nippon Telegraph and Telephone Corporation, Inc. Complex Communications Research Laboratory (72) Inventor Yasunari Ikeda 6-7 Kita-Shinagawa, Shinagawa-ku, Tokyo No. 35 Sony Corporation (72) Hideo Morita, 6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo No. 35 Sony Corporation (72) Yukino Kurata, 6-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Within Sony Corporation (56) References JP-A-61-159883 (JP, A) JP-B-50-28126 (JP, B1)

Claims (1)

[Scope of utility model registration request] 1. A video signal from an image pickup means and an audio signal from a transmitter are transmitted as a transmission signal through an encoding circuit and a multiplexing synthesis circuit, respectively, and a reception signal is supplied to a demultiplexing circuit and a decoding circuit. In a television telephone device in which the video signal and the audio signal obtained as described above are respectively supplied to a receiver and a receiver, a switch circuit for switching the reception signal and the transmission signal to the demultiplexing circuit, and the decoding circuit A mute circuit for muting an audio signal supplied from the circuit to the receiver, and a controller for switching the mute circuit to a mute state when the transmission signal is supplied to the demultiplexing circuit through the switch circuit. A television telephone device.