JPH11112955A - Remote conference system and terminal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase channel utilization efficiency. SOLUTION: An input image from a camera 12 is coded by an image coding decoding circuit 18, and an input voice to a microphone 22 is coded by a voice- coding decoding circuit 26. A multiplexer demultiplexer circuit 28 multiplexes coded image data, coded voice data and communication data from a system control circuit 10. The multiplexed data are sent to an opposite party terminal via a network interface 30 and a public channel. Terminal equipment exchange information related to a display size of an image from the opposite party terminal equipment. The system control circuit 10 controls the image coding decoding circuit 18 and the multiplexer demultiplexer circuit 28, in response to an image display size at the opposite party terminal equipment for adjusting a transmission data amount of image information. A compression rate of the image coding decoding circuit 18 is changed, in response to a change in a transfer rate assigned to the image. The opposite party terminal equipment stops the transmission of the image, when the image sent from this terminal equipment is not displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a remote conference system and a terminal device.

[0002]

2. Description of the Related Art Recently, a video camera connectable to a computer has become available at a low price, and it has become relatively easy to realize a remote conference between computers using both video and data. In such a remote conference system, a window for displaying an image from a communication partner and a window for a data conference are separately set on a computer screen. Usually, the size of these windows, particularly the data conference window, can be freely changed.

[0003]

In the prior art, an image window and a data conference window are displayed together on the same limited screen. Therefore, during a conference centered on a data conference, an image window is displayed. Is in the way. Normally, the user himself closes the image window and proceeds with the conference using the voice and data conference window. But,
Also during this time, since the encoded image data is transmitted on the line, there is a problem that the line use efficiency is poor.

[0004] It is an object of the present invention to solve such a problem and to present a remote conference system and a terminal device with improved line use efficiency.

[0005]

According to the present invention, there is provided:
Information regarding the presence / absence and size of an image transmitted from the partner terminal is exchanged between the terminal devices. Then, the compression ratio of the image to be transmitted is changed according to the image display size at the partner terminal. In an extreme case, when the image is not displayed on the partner terminal, the image transmission is stopped.

[0006] Thus, the ratio of the image data occupied in the transmission medium can be changed according to the actual use, and the line utilization efficiency can be greatly improved.

[0007]

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

FIG. 1 is a schematic block diagram of a terminal according to an embodiment of the present invention. Reference numeral 10 denotes a system control circuit that controls communication between the entire terminal and a partner terminal, 12 denotes a camera as an image input unit, 14 denotes a camera signal processing circuit that processes an output signal of the camera 12, and 16 denotes a camera 12 and a camera signal. A camera control circuit 18 for controlling the processing circuit 14,
An image encoding / decoding circuit for encoding an image signal from the camera signal processing circuit 14 and decoding an encoded image (usually, an image from a partner terminal); A scaling circuit for scaling the image signal decoded at 18 to an arbitrary display size.

Reference numeral 22 denotes a microphone as voice input means;
Is a speaker as an audio output means, 26 is a microphone 22
This is a voice encoding / decoding circuit that encodes a voice signal from the terminal and decodes the coded voice signal (usually, a voice signal from a partner terminal).

Reference numeral 28 denotes a network interface which multiplexes the encoded image signal from the image decoding / decoding circuit 18, the encoded audio signal from the audio encoding / decoding circuit 26, and the data and control signal from the system control circuit 10. 30 and separates the information received from the network interface 30 into a coded image signal.
The demultiplexing circuit supplies an encoded audio signal to the audio encoding / decoding circuit 26 and other data to the system control circuit 10. The network interface 30 is an interface with a data transmission line such as a public line.

Reference numeral 32 denotes a monitor for displaying an image (such as a CRT or a liquid crystal display panel). Reference numeral 34 denotes a monitor for displaying information from the system control circuit 10 and information sent from the scaling circuit 20 via the system control circuit 10. Reference numeral 32 denotes a display processing circuit for performing processing for display, and reference numeral 36 denotes an operation device (keyboard, switches, mouse, etc.) for inputting various instructions to the system control circuit 10.

The operation of the embodiment will be described.

First, the flow of image and audio encoding will be described. The camera signal processing circuit 14 performs adjustment processing such as exposure and white balance on the image signal from the camera 12 under the control of the camera control circuit 16, and applies the adjustment processing to the image encoding / decoding circuit 18. The image encoding / decoding circuit 18 encodes the image signal from the camera signal processing circuit 14 by a known method. On the other hand, the audio encoding / decoding circuit 26
The audio signal input from 2 is also encoded by a known encoding method. The image signal encoded by the image encoding / decoding circuit 18 and the audio signal encoded by the audio encoding / decoding circuit 26 are applied to a demultiplexing circuit 28. Data and control information from the system control circuit 10 are further applied to the demultiplexing circuit 28. The demultiplexing circuit 28 multiplexes the data, and the multiplexed data is transmitted to the partner terminal via the network interface 30 and the public line network.

The information transmitted from the partner terminal is processed as follows. That is, information from the partner terminal is input to the demultiplexing circuit 28 via the network interface unit 30,
Here, it is separated into encoded image data, encoded audio data, and communication data (including control data), and supplied to the image encoding / decoding circuit 18, the audio encoding / decoding circuit 26, and the system control circuit 10, respectively. .

The audio encoding / decoding circuit 26 decodes the encoded audio data from the demultiplexing circuit 28 and
4 is applied. Thereby, the sound from the partner terminal is output from the speaker 24.

The image coding / decoding circuit 18 decodes the coded image data from the demultiplexing circuit 28 and applies it to the scaling circuit 20. The enlargement / reduction circuit 20 is also supplied with information on the display position and the display size of the received image on the screen from the system control circuit 10. The enlargement / reduction circuit 20 receives the received image from the image encoding / decoding circuit 18. Is scaled according to the specified display size, and output at a timing corresponding to the specified display position. System control circuit 10
Supplies the image signal from the scaling circuit 20 to the display processing circuit 34 as it is, and supplies other information to be displayed to the display processing circuit 34. The display processing circuit 34 converts the information into a signal suitable for the monitor 32 and
Feed to 2. Thus, the received image and other information from the system control circuit 10 are displayed on the screen of the monitor 32.

In this embodiment, information on the display size of an image and the presence / absence of display is exchanged between both terminals. The system control circuit 10 controls the image encoding / decoding circuit 18 and the demultiplexing circuit 28 according to the image display size of the partner terminal,
The data amount of the image information to be transmitted or the transfer rate for the image is adjusted. The compression rate in the image encoding / decoding circuit 18 is changed by changing, usually reducing, the transfer rate assigned to the image. In extreme cases, if the image sent by you is not displayed on the other device,
Cancel image transmission.

[0018]

As can be easily understood from the above description, according to the present invention, the image transmission is controlled in accordance with the use form of the transmitted image, and the image transmission is stopped when the image is not displayed on the partner side. Therefore, the line utilization efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of an embodiment of the present invention.

[Explanation of symbols]

 10: System control circuit 12: Camera 14: Camera signal processing circuit 16: Camera control circuit 18: Image encoding / decoding circuit 20: Enlargement / reduction circuit 22: Microphone 24: Speaker 26: Audio encoding / decoding circuit 28: Demultiplexing Circuit 30: Network interface 32: Monitor 34: Display processing circuit 36: Operating device

Claims (4)

[Claims] 1. A remote conference system for communicating information including a moving image between terminal devices separated from each other, wherein said terminal devices exchange information on the presence / absence and size of an image transmitted from a partner terminal. A remote conference system for changing a compression ratio of an image to be transmitted according to an image display size at a partner terminal. 2. The remote conference system according to claim 1, wherein when no image is displayed on the partner terminal, the image transmission is stopped. 3. A terminal device for exchanging information including a moving image with a partner terminal connected via a communication line, wherein the terminal device receives information on a display size of an image to be transmitted at the partner terminal. A terminal device for compressing and transmitting an image under a compression condition corresponding to the display size. 4. The terminal device according to claim 3, wherein image transmission is stopped when no image is displayed on the partner terminal.