Audio and video telecommunication system with remote monitoring function and remote device control function

Claims

We claim:

1. A video conversion/monitoring system in which at least one end station terminal system and one center station terminal system are linked through a communication line which carries video and audio information directly between said end station terminal system and said center station terminal system,

wherein said end station terminal system comprises a first videoconference unit including:

first video input means for entering a monitoring image of a wide area of a room in which said unit is located,

second video input means for entering an image of a visitor;

detection means for detecting a state of a talking person in said room; and

first selection means for selecting one of said first video input means and second video input means;

wherein said center station terminal system comprises a second videoconference unit including:

video input means for entering an image, video output means for displaying an image sent from said end station terminal system,

call control means for implementing calling and disconnection for said end station terminal systems,

second selection means for selecting one end station terminal system from other end station terminal systems,

switching means for controlling said first selection means of said end station terminal system to switch between said first video input means and second video input means, and

video conversation/monitoring system control means for controlling said second video conference unit, said second selection means, said switching means and all of said end station terminal systems; and

wherein said communication line includes a digital communication line included within an integrated-service digital communication network.

2. A video conversation/monitoring system according to claim 1, wherein said end station terminal system each further includes:

first notification means for indicating the presence or absence of a manager in a room of said first video-conference unit; and

second notification means for indicating that a conversation a visitor or manager using said video conversation/monitoring system involves an emergency, and

wherein said center station terminal system includes monitoring means for collecting, storing, displaying and maintaining information provided by said detection means, said first notification means, and said second notification means of said end station terminal systems.

3. A video conversation/monitoring system in which a plurality of end station terminal systems and one center station terminal system are linked through a communication line and video and audio information is transferred between said end station terminal systems and said center station terminal system,

wherein each of said end station terminal systems comprise:

detection means for detecting entry and exit of a visitor into and from a room where said end station terminal system is installed,

a video-phonic conversation unit for sending and receiving video and audio information to and from said center station terminal system, and

notification means for notifying the center station terminal system of a conversation request;

wherein said center station terminal system comprises:

a video-phonic conversation unit for sending and receiving video and audio information to and from said end station terminal system, and

system control means for controlling said plurality of end station terminal systems;

wherein said communication line is a digital communication line of an integrated-service digital communication network,

wherein, when said detection means detects the entry of a visitor in a room of a second one of said plurality of end station terminal systems during a conversation between a first one of said end station terminal systems and said center station terminal system, said video-phonic conversation unit of the second end station terminal system sends a call establishment signal including a come-in notification signal to said center station terminal system and said center terminal station indicates a status of the room and starts to monitor the room in response to the come-in notification signal, and further said notification means sends a conversation request notification signal to said center station terminal system in response to the visitor's entry or exit so as to initiate a conversation with an operator at the center station terminal system, and

wherein, when the center terminal station system received the conversation request notification signal from the second end station terminal system during a conversation with the first end station terminal system with a call, the system control means of the center terminal station system places the first end terminal station system in a call holding state and establishes a call with the second end station terminal system to establish a conversation therewith, and when the conversation with the second end station terminal system is completed, the system control means re-establishes the call with the first end station terminal system to resume the conversation.

4. A video conversation/monitoring system in which one or more end station terminal systems and one center station terminal system are linked through a communication line and video and audio information is transferred between said end station terminal systems and said center station terminal system,

wherein said end station terminal systems each comprises: first video-phonic conversation means including first video input means for entering a monitoring image of a room, second video input means for entering an image of a visitor in the case of having a conversation, video output means for releasing an image, audio input means for entering a sound, audio output means for releasing a sound, video coding/decoding means that transacts video signals with said first or second video input means and said video output means and implements the coding and decoding between the video signals and a first digital signal, audio coding/decoding means that transacts audio signals with said audio input means and said audio output means and implements the coding and decoding between the audio signals and a second digital signal, and multi-media multiplex communication control means that implements the multiplex separation control for the first digital signal, second digital signal and a monitoring control signal of said end station terminal system, sends and receives the video and audio signals over a digital communication line, and controls said first video input means, said video output means, said audio input means, said audio output means, said video signal coding/decoding means and said audio signal coding/decoding means; detection means for detecting the entry and exit of a visitor to/from the room; first selection means for selecting one of said first video input means and second video input means; first notification means for indicating the presence or absence in the room of the manager of said first video-phonic conversation means; and a second notification means for indicating that the conversation of the visitor or the manager who is using said video conversation/monitoring system tells a matter of emergency,

wherein said center station terminal system comprises: second video-phonic conversation means including video input means for entering an image, video output means for releasing an image, audio input means for entering a sound, audio output means for releasing a sound, video coding/decoding means that transacts video signals with said video input means and said video output means and implements the coding and decoding between the video signals and a first digital signal, audio coding/decoding means that transacts audio signals with said audio input means and said audio output means and implements the coding and decoding between the audio signals and a second digital signal, and multi-media multiplex communication control means that implements the multiplex separation/conversion for the first digital signal, second digital signal and a monitoring control signal of said center station terminal system, sends and receives the video and audio signals over the digital communication line, and controls said first video input means, said video output means, said audio input means, said audio output means, said video signal coding/decoding means and said audio signal coding/decoding means; call control means that implements the one-touch calling and disconnection for said end station terminal systems; second selection means for selecting one end station terminal system out of said end station terminal systems; switching means for controlling said first selection means of said end station terminal system to select one of said first video input means and second video input means; monitoring means that collects, stores, displays and monitors information provided by said detection means, said first notification means and said second notification means of said end station terminal systems; and video conversation/monitoring system control means for controlling said second video-phonic conversation means, said second selection means, said switching means, said monitoring means and the entirety of said end station terminal systems, and

wherein said communication line comprises a digital communication line of an integrated-service digital communication network.

5. A video conversation/monitoring system according to claim 4, wherein images treated in said video conversation/monitoring system comprises moving images or still images.

6. A video conversation/monitoring system according to claim 4, wherein said center station terminal system and said end station terminal systems each include one or more data communication terminal units such as a facsimile unit, said data communication terminal units performing the transmission and reception of text and graphic information over one digital communication line during the video-phonic monitoring operation.

7. A video conversation/monitoring system according to claim 4 performing the transmission and reception of the monitoring control signals of said center station terminal system and said end station terminal systems through a signal channel of said digital communication line.

8. A video conversation/monitoring system according to claim 7, wherein a terminal system that intends to send a monitoring control signal transmits the monitoring control signal in terms of incoming sub-address information elements of a call establishment message, and a terminal system that receives the call establishment message disconnects the line by making a display of the reason coded based on a standard specific to the generation source, without connecting the call.

9. A video conversation/monitoring system according to claim 4, wherein said center station terminal system and said end station terminal systems examine the origination number information element in the call establishment message at the incoming of a call and log the incoming call, but do not respond to an incoming call from a terminal station that is not registered in advance.

10. A video conversation/monitoring system according to claim 9, wherein said end station terminal systems each send the logged incoming call information as the monitoring control signal mentioned in claim 4 to said center station terminal system, said center station terminal system logging incoming call information sent from the end station terminal systems together with incoming call information from stations that are not registered in advance.

11. A video conversation/monitoring system according to claim 4, wherein said first video-phonic conversation means of said end station terminal system is accommodated in an integrated cabinet and is used by being installed on the top of a desk or table.

12. A video conversation/monitoring system according to claim 11, wherein said end station terminal system is such that said integrated cabinet consists of a main unit section in which at least said second video input means, video output means and audio output means are accommodated and a base section that supports said main unit section, said main unit section being linked to said base section through such a tilt-swivel mechanism that said main unit section is swingable by certain angles vertically and horizontally with respect to said base section.

13. A video conversation/monitoring system according to claim 4, wherein said first video-phonic conversation means, said first selection means, said first notification means and said second notification means are used by being accommodated in an integrated cabinet.

14. A video conversation/monitoring system according to claim 13, wherein said end station terminal system is such that said integrated cabinet accommodates at least said second video input means, video output means, audio input means and audio output means, said second video input means being attached to the top front section of said cabinet, said video output means being attached to the mid-front section of said cabinet at an angle of about 50.degree. with respect to the horizontal direction.

15. A video conversation/monitoring system according to claim 4, wherein said end station terminal system is such that only said first video input means, second video input means, video output means, audio input means, audio output means, second notification means and detection means are placed in the room where a visitor comes in, and devices that constitute said end station terminal system except for said first video input means, second video input means, video output means, audio input means, audio output means, second notification means and detection means are placed in another room where no visitor is allowed to come in.

16. A video conversation/monitoring system according to claim 15, wherein said end station terminal system is such that said second video output means and second audio output means are placed in the room where no visitor is allowed to come in, and wherein the manager of said end station terminal system monitors a visitor or monitors the state of conversation of the visitor.

17. A video conversation/monitoring system according to claim 4, wherein said second video-phonic conversation means of said center station terminal system is accommodated in an integrated cabinet and is used by being installed on the top of a desk or table.

18. A video conversation/monitoring system according to claim 4, wherein said end station terminal system makes a call to said center station terminal system in response to the detection of the entry of a visitor to the room by said detection means.

19. A video conversation/monitoring system according to claim 18, wherein said end station terminal system includes third notification means for notifying a request of a visitor to have a video-phonic conversation with said center station terminal system, and wherein the image delivered to the image output means of said center station terminal system at the establishment of call between said center station terminal system and said end station terminal system is an image that is entered to the first image input means of said end station terminal system, and wherein in response to the operation of said third notification means by the visitor of said end station terminal system, said switching means and first selection means are controlled to switch the image that is delivered to the image output means of said center station terminal system to the image that is entered to the second image input means of said end station terminal system.

20. A video conversation/monitoring system according to claim 19, wherein the image delivered to the image output means of said end station terminal system is an initial image, such as the guidance of video conversation/monitoring system, until the image that is delivered to the image output means of said center station terminal system is switched to the image that is entered to the second image input means of said end station terminal system, and is switched to the image that is entered to the video input means of said center station terminal system in response to the switching of the image that is delivered to the image output means of said center station terminal system to the image that is entered to the second video input means of said end station terminal system so that a video-phonic conversation takes place.

21. A video conversation/monitoring system according to claim 4, wherein on completion of video conversation/monitoring for a visitor, said end station terminal system notifies to said center station terminal system the exit of the visitor in response to the detection of the exit of the visitor from the room by said detection means of said end station terminal system, and said center station terminal system disconnects the communication with said end station terminal system.

22. A video conversation/monitoring system according to claim 4, wherein in response to the call operation by said calling control means of said center station terminal system, said center station terminal system makes a call to said end station terminal systems to implement the monitoring of said end station terminal systems or carry out a video-phonic conversation with a visitor or manager of said end station terminal system.

23. A video conversation/monitoring system according to claim 4, wherein in response to the disconnecting operation by said call control means of said center station terminal system, said center station terminal system implements the disconnection of said end station terminal systems to terminate the monitoring of said end station terminal systems or carries out a video-phonic conversation with a visitor or manager of said end station terminal system.

24. A video conversation/monitoring system according to claim 4, wherein in response to the selection of said end station terminal systems that undergo a video conversation/monitoring by said second selection means of said center station terminal system, said center station terminal system carries out the video-phonic conversation with a visitor or manager of said end station terminal system.

25. A video conversation/monitoring system according to claim 4, wherein if there arise requests of video conversation/monitoring from more than one end station terminal system, said second selection means of said center station terminal system selects one end station terminal system that undergoes a video conversation/monitoring, with remaining end station terminal systems being kept waiting for video conversation/monitoring, and the monitoring control signals of all end station terminal systems that request the video conversation/monitoring are transferred through a signal channel of said digital communication line so that said center station terminal system implements the monitoring of said end station terminal systems.

26. A video conversation/monitoring system according to claim 25, wherein said end station terminal systems that are waiting for the video conversation/monitoring have the video output means and audio output means thereof releasing an image and sound to notify a wait to visitors or managers of said end station terminal systems.

27. A video conversation/monitoring system according to claim 4, wherein the image delivered to the image output means of said center station terminal system at the establishment of call between said center station terminal system and said end station terminal system is an image that is entered to the first image input means of said end station terminal system, and wherein the operator of said center station terminal system controls said switching means and said first selection means to switch the image that is delivered to the image output means of said center station terminal system to the image that is entered to the second image input means of said end station terminal system upon detecting the approach of a visitor to the second image input means of said end station terminal system or detecting a request of the visitor to have a video-phonic conversation with said center station terminal system.

28. A video conversation/monitoring system according to claim 27, wherein the image delivered to the image output means of said end station terminal system is an initial image, such as the guidance of video conversation/monitoring system, until the image that is delivered to the image output means of said center station terminal system is switched to the image that is entered to the second image input means of said end station terminal system, and is switched to the image that is entered to the video input means of said center station terminal system in response to the switching of the image that is delivered to the image output means of said center station terminal system to the image that is entered to the second video input means of said end station terminal system so that a video-phonic conversation takes place.

29. A video conversation/monitoring system according to claim 4, wherein the first image input means of said end station terminal system has an image input range that enables the monitoring of at least the whole interior of the room.

30. A video conversation/monitoring system according to claim 29, wherein the first video input means of said end station terminal system has one or both of a zoom function and input direction altering function, with the input range of said first video input means being variable in response to the reception of a command of said center station terminal system through a signal channel of said digital communication line.

31. A video conversation/monitoring system according to claim 4, wherein the second image input means of said end station terminal system has an image input range that enables the shooting of at least the whole body of a visitor.

32. A video conversation/monitoring system according to claim 31, wherein the second video input means of said end station terminal system has one or both of a zoom function and input direction altering function, with the input range of said second video input means being variable in response to the reception of a command of said center station terminal system through a signal channel of said digital communication line.

33. A video conversation/monitoring system according to claim 32, wherein the second image input means of said end station terminal system can be set to have an image input range that enables the shooting of at least the whole body of a visitor.

34. A video conversation/monitoring system according to claim 4, wherein said center station terminal system includes one or both of one or more third video input means, such as a drawing device and video tape recorder, and second audio input means, and sends an image or sound based on said image input means, audio input means, third video input means or second audio input means selectively to said end station terminal system.

35. A video conversation/monitoring system according to claim 4, wherein said center station terminal system includes recording means for recording one or both of an image and sound, said recording means recording one or both of images and sounds sent from said end station terminal systems.

36. A video conversation/monitoring system according to claim 35, wherein an image or sound recorded by said recording means is delivered to the video output means or audio output means of said center station terminal system.

37. A video conversation/monitoring system according to claim 4, wherein said end station terminal system includes recording means for recording one or both of an image and sound, said recording means recording one or both of an image and sound entered to the first video input means, second video input means or audio input means of said end station terminal system.

38. A video conversation/monitoring system according to claim 37, wherein an image or sound recorded by said recording means is delivered to the video output means or audio output means of said end station terminal system, or delivered to the video output means or audio output means of said center station terminal system.

39. A video conversation/monitoring system according to claim 4, wherein said end station terminal system has an arrangement exclusive of the first video input means and first selection means, and said center station terminal system has an arrangement exclusive of the switching means.

40. A video conversation/monitoring system according to claim 39, wherein the second video input means of said end station terminal system has one or both of a zoom function and input direction altering function, with the input range of said second video input means being variable in response to the reception of a command of said center station terminal system through a signal channel of said digital communication line.

41. A video conversation/monitoring system according to claim 40, wherein the second image input means of said end station terminal system is set to have an image input range that enables the monitoring of the whole interior of the room upon detecting the entry of a visitor to the room by the detection means of said end station terminal system.

42. A video conversation/monitoring system according to claim 4, wherein said first or second video-phonic conversation means comprises a video-conference terminal unit, said system control means and said videoconference terminal unit being linked through a general-purpose communication means.

43. A video conversation/monitoring system in which at least one end station terminal system and one center station terminal system are linked through a communication line which carries video and audio information directly between said end station terminal system and said center station terminal system,

wherein said end station terminal system includes a first video-phonic conversation unit comprising:

first video input means for entering a monitoring image of a wide area of a room in which said unit is located,

second video input means for entering an image of a visitor,

video output means for displaying an image,

audio input means for entering a sound,

audio output means for broadcasting a sound,

video coding/decoding means for transacting video signals with said first or second video input means and said video output means and for implementing coding and decoding between the video signals and a first digital signal,

audio coding/decoding means for transacting audio signals with said audio input means and said audio output means and for implementing coding and decoding between the audio signals and a second digital signal, and

multi-media multiplex communication control means for implementing multiplex separation control for the first digital signal, second digital signal, and a monitoring control signal of said end station terminal system, for sending and receiving the video and audio signals over a digital communication line, and for controlling said first video input means, said video output means, said audio input means, said audio output means, said video signal coding/decoding means, and said audio signal coding/decoding means; and first selection means for selecting one of said first video input means and second video input means;

wherein said center station terminal system includes a second video-phonic conversation unit comprising:

video input means for entering an image,

video output means for displaying an image,

audio input means for entering a sound,

audio output means for broadcasting a sound;

video coding/decoding means for transacting video signals with said video input means and said video output means and for implementing coding and decoding between the video signals and a first digital signal,

audio coding/decoding means for transacting audio signal with said audio input means and said audio output means and for implementing coding and decoding between the audio signals and a second digital signal, and

multi-media multiplex communication control means for implementing a multiplex separation/conversion for the first digital signal, second digital signal, and a monitoring control signal of said center station terminal system, for sending and receiving the video and audio signal over the digital communication line, and for controlling said first video input means, said video output means, said audio input means, said audio output means, said video signal coding/decoding means, and said audio signal coding/decoding means; call control means for controlling calls to said end station terminal systems; second selection means for selecting one end station terminal system out of said end station terminal systems; switching means for controlling remotely said first selection means to switch between said first video input means and said second video input means of said end station terminal system; and video conversation/monitoring system control means for controlling said second video-phonic conversation means, said second selection means, said switching means and all of said end station terminal systems; and

wherein said communication line comprises a digital communication line formed within an integrated-service digital communication network.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a multi-media communication system using an Integrated Service Digital Network (ISDN), and more particularly to an ISDN-based video conversation/monitoring system applicable to a complex conversation service system that includes a remote monitoring function.

2. Description of the Related Art

Conventional guidance systems, conversation systems and monitoring systems which communicate images, sounds and data, as well as complex systems that integrate these types of systems, use analog telephone lines, dedicated communication lines, or optical fiber lines or the like. An example of such systems is described in Japanese patent publication JP-A-4-21095 and JP-A-4-315351.

The above-mentioned prior art systems, when an existing analog telephone line is used, has problems in that the transmission line has a limited band width, which consequently makes it difficult to transmit efficiently moving image signals and complex signals that carry sound, images, and control data. Furthermore, such prior art systems typically employ a center station and end station facilities which are of large scale and which necessitate a large installation space.

The above-mentioned prior art systems, when a dedicated line or optical fiber line is used, has problems in that a new transmission line needs to be constructed, the service range and scale are limited by the network construction, all of which make construction of the system very expensive.

The above-mentioned prior art systems, when a public integrated-service digital communication network is used for the communication line, which advantageously removes the need for construction of a new communication line significantly reduces the operating communication cost of the system, has a particular problem in that the system is accessible by unlicensed terminal stations through the public communication line and the handling of information will be intricate for secrecy protection.

SUMMARY OF THE INVENTION

The prevent invention overcomes the deficiencies of the foregoing prior art systems by providing, as a first objective, a compact, simple, and economical video conversation/monitoring system which performs conversation and monitoring through a bidirectional transmission of sounds, images, and data among a plurality of terminal stations.

A second objective of the present invention is to provide a simple and reliable video conversation/monitoring system with an enhanced ability of secrecy protection and performance of conversation and monitoring.

A third objective of the present invention is to provide a video conversation/monitoring system that can be used easily by the user for carrying out conversation and monitoring.

A fourth objective of the present invention is to provide a video conversation/monitoring system that offers an unlimited service range in terms of time and people for carrying out the conversation.

A fifth objective of the present invention is to provide a video conversation/monitoring system that can be arranged flexibly by including various peripheral devices to accomplish a number of versatile uses in addition to offering bidirectional conversation for users.

In order to achieve the above objectives, video conversation/monitoring system of the present invention preferably may be incorporated within a desk-top videoconference unit. This unit, for example, includes a video-phonic conversation means installed in a center station and a plurality of end stations. Bidirectional communication between the center station and the end through stations is made possible through an existing ISDN public line for carrying image, voice, and data signals inclusive of the facsimile. The center station equipment includes a video-phonic conversation means, video input means, video output means, audio input means, audio output means, system controller, facsimile and ISDN line terminating unit. Each end station equipment includes a video-phonic conversation means, system controller, first video input means, second video input means, video output means, audio input means, audio output means, calling means, first notification means, second notification means, detection means, facsimile and ISDN line terminating unit.

The center and terminal stations are given individual registered dial numbers so that the equipments having the registered numbers are linked exclusively, while disallowing the linkage of unlicensed terminal stations, and therefore the system has enhanced information secrecy protection. By the provision of a remote monitoring function based on the first video input means and a remote control function for switching the video input means by the system controller, the video conversation/monitoring system can be designed to be suitable for various guidance services besides the service of video-phonic conversation function.

In the video-phonic conversation means of an end station, a line controller communicates image, sound, and various other types of data signals with the center station equipment through the ISDN network. The first video input means operates to input an image of the whole interior of the end station, the second video input means operates to input the image of a visitor or the like, and the audio input means operates to input sound. These means send the entered images and sound to the center station equipment. The video output means releases the video signal received from the center station, and the audio output means releases the audio signal received from the center station. The calling means detects the visitor's request for conversation with the center station, the first notification means detects the presence or absence the keeper or other person, the second notification means detects the abnormality of the keeper or other person, and the detection means detects the entry or exit of a visitor to/from the room. These means send the detected signals to the center station equipment through the line controller. The facsimile receives through the line controller, text and graphic information sent from the center station, and releases the information.

In the video-phonic conversation means of the center station, the video input means and audio input means operate to input and then send image and sound, respectively, of the center station to the end station equipment. The video output means and audio output means receive image and sound, respectively, from the end station and release them. The facsimile sends text and graphics information to the end station through the line controller. The system controller includes a control panel on which the video and audio signals of the whole system are switched, calls to end stations are controlled and notification signals provided by the calling means, first notification means, second notification means and detection means of end stations are displayed.

The video conversation/monitoring system of the present invention advantageously can be organized by using a commercialized videoconference unit and an existing ISDN public line, instead of dedicated facilities. Consequently, a simple and economical video conversation/monitoring system that performs bidirectional transmission of sounds, images and data can be offered.

The system of the present invention also advantageously is designed to link equipments that have been registered in advance, with the center station equipment controlling the the overall system, and consequently a video conversation/monitoring system with a high secrecy protection ability against violation can be offered.

The video conversation/monitoring system of the present invention, is also advantageous in that a person comes to an end station to use the conversation or monitoring functions of the system is not required to perform intricate operations on the system equipment, but instead can communicate with another person in the center station through a simple operation.

The present invention also can be designed to provide a general-purpose video conversation/monitoring system useful for any person. Such a system can prove to be versatile in that its terminal units can be designed and its camera angle can be set to meet a variety of body sizes of people.

The simple and economical video conversation/monitoring system of the present invention also may be adapted to include, in which various peripheral devices so that communication of high-grade information can be performed while it perform its monitoring operation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the overall arrangement of a video conversation/monitoring system based on this invention;

FIG. 2 is a perspective view of a video conversation/monitoring system based on this invention;

FIG. 3 is a block diagram showing a detailed arrangement of the video conversation/monitoring system based on this invention;

FIG. 4 is a perspective view of the video-phonic conversation unit used in the video conversation/monitoring system of the present invention;

FIG. 5 is diagram showing an example of the manner of use of the inventive video conversation/monitoring system of the present invention;

FIG. 6 is a front view of the control panel of the system controller equipped in the center station to be included in the system of the present invention;

FIG. 7 is a functional block diagram of the video-phonic signal controller used in the end stations of the video conversation/monitoring system of the present invention;

FIG. 8 is a diagram showing the communication procedure (for normal communication) of the video conversation/monitoring system of the present invention;

FIG. 9 is a diagram showing the communication procedure of the video conversation/monitoring system of the present invention;

FIG. 10 is a diagram showing the communication procedure (for automatic calling by center station) of the video conversation/monitoring system of the present invention;

FIG. 11 is a diagram showing the communication procedure (for rejection of calls from unlicensed terminal stations) of the video conversation/monitoring system of the present invention;

FIG. 12 is a diagram showing the communication procedure (for monitoring of all end stations based on the poling function) of the video conversation/monitoring system of the present invention;

FIG. 13 is a diagram showing the communication procedure (for video monitoring of all end stations based on the poling function) of the video conversation/monitoring system of the present invention;

FIG. 14 is a diagram showing an example of display (image entered to the center station equipment) on the video-phonic conversation unit of an end station included in the video conversation/monitoring system of the present invention;

FIG. 15 is a diagram showing an example of display (view of the self station) on the video-phonic conversation unit of an end station included in the video conversation/monitoring system of the present invention;

FIG. 16 is a diagram showing an example of display (view of normal conversation) on the video-phonic conversation unit of an end station based on the video conversation/monitoring system of the present invention;

FIG. 17 is a diagram showing an example of display (guidance prior to the normal conversation) on the video-phonic conversation unit of an end station included in the video conversation/monitoring system of the present invention;

FIG. 18 is a diagram showing an example of display (guidance indicating the busy state of center station) on the video-phonic conversation unit of an end station included in the video conversation/monitoring system of the present invention;

FIG. 19 is a perspective view of an example of the extended video conversation/monitoring system based