JPH02266784A - Video telephone system - Google Patents

Abstract

PURPOSE:To enable a speaker to speak with the other party without transmitting the picture which may infringe on his privacy by eliminating unnecessary images other than the image of the speaker to transmit the picture. CONSTITUTION:In transmission-side terminal 20, a camera 7 converts the image of the speaker being in focus and the other images being out of focus to a strong picture analog signal and a weak picture analog signal respectively, and a filter 8 allows only the former analog signal to pass through, and a picture encoder 9 encodes the signal corresponding to the image of the speaker, which passes the filter 8, to a digital code and transmits it to the other-party terminal through a terminal adapter 21 and an ISDN network 22. Still picture information preliminarily set and inputted to a still picture transmission equipment 13 is transmitted to the other-party terminal through the terminal adapter 21 and the ISDN network 22 and is synthesized with the image of the speaker of the transmission-side terminal by a picture synthesizing device 10 and is displayed on a monitor. Thus, unnecessary images other than the image of the speaker are not transmitted to the other-party terminal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to an improvement of a video telephone system in an ISDN application system.

[Prior art] In a conventional videophone system, the image captured by the camera of the videophone is converted into an analog signal, and the
(transfer)/int with a real transmission line, i.e.
The image was transmitted without restrictions due to line type, transmission control procedures, etc., and the image was restored to its original form by the receiver's monitor.

[Problems to be Solved by the Invention] As mentioned above, in the conventional videophone system, all images captured by the camera are transmitted. Therefore, not only the image of the person using the telephone, but also the image captured by the camera is transmitted.
Since unnecessary images other than the person's image (for example, an image behind the person) are also transmitted, there is a drawback that depending on the location of the videophone system, privacy may be violated.

[Means for Solving the Problems] The videophone system of the present invention has the following means.

a.) The focused image has a strong image analog signal,
A camera that converts out-of-focus signals into weak analog image signals and outputs them. C) An image encoding device that converts the image analog signal received from the filter into an image digital signal and transmits it; d) A still image transmitter that converts still image information input in advance into an image digital signal and outputs the image digital signal. , e) Place the audio digital signal output from the audio encoder on the first B channel, place the image digital signal output from the image encoder on the second D channel, and output from the still image transmitter. The digital image signal is sent to the ISDN network on the D channel, and the multiplexed 2B+D channel signal received from the ISDN network is sent to the first and second channels.
f) a call processing device that controls the call processing and operation timing of the terminal adapter; g) a second B channel received from the terminal adapter; an image synthesis device that receives a channel image digital signal and a D channel image digital signal and synthesizes these two image digital signals; h) decodes the image digital signal received from the image synthesis device and converts it into an image analog signal; Decoding device for images to be transmitted.

[Operation] At the transmitting side terminal, the camera converts the in-focus image of the speaker into a strong image analog signal and the out-of-focus image of the person other than the speaker into a weak image analog signal, and outputs the signals to the filter. The filter passes only a strong image analog signal among the input image analog signals and outputs it to the image encoding device. Therefore, the image encoding device digitally encodes the filtered strong analog signal, i.e. the signal corresponding to the image of the speaker, to the terminal adapter and the I'.
It is sent to the other party's terminal via the SDN network. As a result,
Camera focus does not match <11. That is, unnecessary images of those other than the speaker are not sent to the other party's terminal.

Second, the still image information that has been set and input in advance to the still image transmitting device is sent to the other party's terminal via the terminal adapter and SDN network, and then the image synthesis device transmits the information to the speaker of the transmitting terminal. is combined with the image and displayed on the monitor.

[Example] Next, the present invention will be explained with reference to the drawings.

The figure is a block diagram showing one embodiment of the present invention.

The video phone 20 connects to ISDN via the terminal adapter 21.
1'122 and ■Connected according to the interface standards. This ■interface has a 2B+D channel configuration. The B channel indicates a 64 kbps information channel, and one of the two B channels is called the B channel and the other is called the 82 channel. The D channel represents a 16 kbps control channel.

In addition, in the video telephone system of the present invention, one of the B channels, for example, the B1 channel, carries audio information, the other B channel, for example, the B2 channel, carries image information, and the D channel carries the image of the B2 channel in addition to normal control information. Transmission is performed by assigning image information different from information.

Furthermore, the B1 channel and the 82nd channel are equivalent, and there is no operational difference even if these two channels are exchanged.Next, the configuration of the videophone system of this embodiment will be explained.

The part within the broken line in the figure indicates a video telephone 20, and this video telephone 20 is constructed as follows.

1 is a transmitter that converts audio into an analog signal; 2 is a transmitting amplifier that amplifies the analog audio signal input from the transmitter 1; and 3 is a transmitter that encodes the audio analog signal input from the transmitter amplifier 2 into an audio digital signal. This is an audio encoding device that converts and outputs the audio data.

4 is a voice decoding device that decodes voice information from the other party, that is, a coded voice digital signal into a voice analog signal; 5 is a receiving amplifier that amplifies the voice analog signal input from the voice decoder 4; 6 is the receiving amplifier 5
This is a handset that converts audio analog signals input from a receiver into audio.

7 is a camera that converts images into image analog signals;
The focal length of the camera 7 is adjusted so that the person talking in front of the video phone 20 is in focus, but the background of this person is out of focus. Further, this camera 7 is configured to convert an in-focus image into a strong image analog signal, and to convert an out-of-focus image into a weak image analog signal. Reference numeral 8 denotes a filter that compares the strength of the image analog signal input from the camera with a reference level, outputs the image analog signal that is equal to or higher than the reference level, and blocks other image analog signals and does not output them. Here, the reference level of the filter 8 is set such that a strong image analog signal corresponding to the image of the speaker passes through the filter 8, and a weak image analog signal corresponding to the image behind the speaker is blocked by the filter 8. It is set.

Therefore, only the image of the speaker is output from the filter 8.

Reference numeral 9 denotes an image encoding device that encodes the image analog signal inputted from the filter 8 into an image digital signal and outputs the same.

Reference numeral 10 denotes an image synthesis device that receives two types of image digital signals transmitted from the other party, synthesizes these two types of image digital signals, and generates and outputs a new image digital signal. 11 is an image decoding device that decodes the image digital signal received from the image synthesis device 10 into an image analog signal; 12 is a monitor that converts the image analog signal received from the image decoding device 11 into an image and displays the image; This is a still image transmitting device that outputs an image digital signal of a fixed image whose settings are input.

A call processing device 14 performs call control necessary when the terminal adapter 21 connects to the ISDN network 22 using the D channel, controls various timings of the terminal adapter 21, and the like.

Terminal adapter 21 connects video phone 20 and ISDN#12
In order to exchange audio information and image information with 2, the following interface functions are provided.

■One set of audio digital signal input/output interface functions for exchanging audio information with the videophone 20, ■Two sets of image digital signal input/output interface functions for exchanging image information with the videophone 20, ■ISDN A network interface function for exchanging audio information, image information, and control information with the network 22.

With this network interface function, the ISDN network 22
2I3+1]? :' The channel is divided into three channels, B0 channel, B2 channel, and D channel, and is output to the videophone 20 side, and the 5° videophone n2 (B1 channel, B, channel input from the monthly rule) is output to the videophone 20 side. , and the D channel is 2
It is configured as B+D and output to the ISDN network 22 side.

The specific operation of this terminal adapter 21- is as follows.

(2) The audio digital signal input from the audio encoder 3 is sent to the ISDN network 22 on the B1 channel. In addition, the audio digital signal transmitted from the ISDN network 22 by being multiplied by channel B is sent to the audio decoding device 4.
Send to.

(2) The image digital signal input from the image encoding device 9 is sent to the ISDN&M 22 on 82 channels. The image digital signal multiplied by the B2 channel and sent out from the ISDN network 22 is sent to the image synthesis device W1.
Send to 0.

■ The image digital signal input from the still image transmitting device 1-3 is put on the D channel and transmitted over the ISDN network 224m 7
Also, add the D channel from 1 network 22 to ISO) 1.
The image digital signal sent out by the image synthesizer 1-
Send to 0.

Note that from the terminal adapter 21 to the ISDN network 2217. The line through which information is transmitted from the ISDN network 22 to the terminal adapter 21 is called the downlink.
The operation C of the telephone system will be explained. In addition, 1)
! Show me! The following explanation will be given assuming that the terminal adapter 21 and the video telephone 20 are placed opposite each other with the ISDN network 2 in between.

(1) Line Connection Suppose now that the user uses the call processing device 14 to dial a destination that is not 16 degrees in line, so that destination dial information is not sent to the terminal adapter 21.

The terminal adapter 21- uses the D channel to connect to the N5DN network 2 based on the dial information sent from the call processing device 14.
After connecting 1 to 2, connect to the other party's terminal. When this connection is completed, the terminal adapter 21 connects the output of the audio encoder 3 to the B1 channel of the -L line, connects the output of the image encoder 9 to the Bzf-Yanel of the uplink, and transmits still images. Connect the output of device 1-3 to the D channel of the tri-line. In addition, on the downlink from ISDN 22, the Bl channel carrying the audio digital signal is connected to the input of the audio decoding device 4, and the I3□ channel and D channel carrying both image digital signals are combined into an image. Connect to two inputs of device 10.

In the above manner, the video telephone 20 and the ISDN network 22 are connected to each other.
A line connection is made between the two.

(2) Sending and receiving voice information When the user stands in front of the camera 7 and speaks from the transmitter 1, this voice passes through the transmitter 1, is converted into an analog signal, is amplified by the transmitter side amplifier 2, and then After being converted into an audio digital signal by the audio encoding device 3, the signal is input to the terminal adapter 21, which sends it to the other party's terminal via the ISDN network 22 on the uplink Bl channel. ,! 5.

On the other hand, downlink B via ISD N9M22
The audio-digital signal from the other party's terminal sent on the l channel is separated from other signals such as image signals by the terminal adapter 21, and sent to the audio decoding device 4 where it is decoded into an audio analog signal. After being amplified by the receiving amplifier 5, the voice is output from the receiver 6.

Audio information is exchanged as described above.

(3) Transferring and receiving image information The camera 7 is in focus and converts the speaker's image into a strong image analog signal, and the out-of-focus images other than the speech are converted into weak image analog signals, which are output to the filter 8. . The filter 8 passes only strong image analog signals among the input image analog signals and outputs them to the image encoder 9 .

In the image encoding device 9, the filter 8 is passed through 1. ? , = strong analog signal.

That is, a signal corresponding to the image of the speaker is digitally encoded and transmitted to the terminal adapter 21. The terminal adapter 21 is
The image digital signal corresponding to the image of the speaker inputted from the image encoding device 9 is sent to the IS by putting it on the B2 channel of the uplink.
It is sent to the other party's terminal via the DN network 22. Furthermore, the still image information that has been set and input in advance to the still image transmitting device 13 is converted into an image digital signal and inputted to the terminal adapter 21, and then transferred to the uplink D channel where call processing control has been completed. It is sent to the other party's terminal via the ISDN network 22.

On the other hand, the image digital signal corresponding to the image of the speaker at the other party's terminal sent from the ISDN network 22 on the downlink channel 82 is separated from other signals by the terminal adapter 21, and then sent to the image synthesis device 10. is input to one input terminal of On the other hand, the still image digital signal sent from the still image transmitting device 13 of the other party's terminal via the ISDN network 22 on the D channel of the downlink is input to the terminal adapter 21 and transmitted to other terminals. 0 which is input to the other input terminal of the image synthesis device 10 after being separated from the signal of
The image synthesis device 10 synthesizes the two image digital signals and sends the synthesized image digital signal to the image decoding device 9. The image decoding device 11 converts the sent image digital signal into an image analog signal. Decrypt to monitor 1
Send to o. As a result, the image of the other party's speaker is displayed on the monitor 10, combined with the still image.

Image information is exchanged as described above.

[Effects of the Invention] As explained above, the videophone system of the present invention has the following advantages:
Since unnecessary images other than the image of the person speaking (for example, an image behind the person) can be excluded from transmission, images that may violate privacy depending on the location of the videophone system are transmitted. This has the effect that you can talk to the other party without having to do anything.

Furthermore, by transmitting image information of a still image using the D channel, it is possible to display a composite image of the speaker and an arbitrary still image. Therefore, any still image can be displayed in the background of the speaker's image instead of unnecessary images other than the speaker's image, allowing the user to talk while viewing a more natural image. It also has effects.

[Brief explanation of drawings]

The figure is a block diagram showing one embodiment of the present invention. 3... Audio encoding device, 4... Audio decoding device, 7
Camera, 8 Filter, 9 Image encoding device, 10 Image synthesis device, 11 Image decoding device, 12 Monitor, 13 Still image transmission Device,
14... call processing device, 20... video telephone, 21
...Terminal adapter, 22...ISDN network.

Claims (1)

[Claims] In a videophone system that communicates image information and audio information using an ISDN network that multiplexes two 64 kbps B channels and one 16 kbps D channel, a focused image is strong. A camera that converts out-of-focus images into a weak image analog signal and outputs the image analog signal, and a camera that judges the strength of the image analog signal received from this camera and determines whether the image analog signal has a strength equal to or higher than a predetermined reference level. An image encoding device that converts the image analog signal received from this filter into an image digital signal and transmits it, and a still image that converts still image information input in advance into an image digital signal and outputs the still image signal. The audio digital signal output from the audio encoding device of the transmitting device is placed on the first B channel, the image digital signal output from the image encoding device is placed on the second B channel, and the still image signal is output from the still image transmitting device. ISD by putting the image digital signal on the D channel
N network and received from the ISDN network.
a terminal adapter that separates and outputs a B+D channel signal into three signals, a first and second two B channels, and one D channel; a call processing device that controls call processing and operation timing of this terminal adapter; an image synthesis device that receives a second B-channel image digital signal and a D-channel image digital signal received from a terminal adapter and synthesizes the two image digital signals; A video telephone system includes an image decoding device that decodes and converts the image into an analog image signal and transmits the same, and a monitor that converts and displays the image analog signal inputted from the image decoding device as an image.