FR2699034A1 - Telecommunications system for video conferencing - has audio-video interface for individual users with multiple switchable audio-video units in conference centre accessing PABX - Google Patents

Abstract

The conference centre (9C) has several telephone terminals (9C2), video monitors (9C3) and video recorders (9C4), together with a tape recorder (9C5). Video and sound signals from the different units are sent to a switch (4) where a choice of presenters is made. Access to the telephone network is then via a server (5) to the PABX. Individual users (9A,9B) have a command mechanism (9A11) together with sound and visual collection (9A1,9A2) together with monitors and recorders. Each videophone is connected to the PABX by its telephone terminal. When the user activates the command device he can then establish multi- or two-way communication with an existing conference or other users. ADVANTAGE - Allows extra participants to join video conference link up without losing original participants.

Description

TELECOMMUNICATIONS FACILITY WITH VIDEO CAPACITY.

The invention relates to a telecommunications installation with videophone capacity, notably offering a third party entry option on established videoconferencing.

 It is possible to make teleconferences between two telecommunications installations, generally distant, which have videophone capacities, by means of a telecommunications network, of the digital type with service integration, through which digital audiovisual information originating from of each of the installations are exchanged.

For this purpose, each installation has video and audio means, for example cameras, monitors, speakers, microphones, one or more document readers, one or more video recorders, as well as sets or other telephones for users. . Each installation also has means, of codec type, for digitizing the analog video / audio signals, for sending the digital signals obtained towards the digital telecommunications network and for inversely receiving from the latter digital video / audio signals in order to convert them into analog signals for the benefit of the users served by the installation.

The codec type means mentioned above are preferably pooled at the level of an installation, which allows a user equipped with video and audio means to establish videophone communication with a correspondent distant from a similar site, through the digital network, via a codec of the installation to which it is attached; a videophone communication can also be established following a call from a distant correspondent.

However, a user in videophone communication with a remote correspondent, for example from a videoconferencing room simultaneously exploitable by several parties or from an individual office, may wish to involve a third party during the communication, without this the latter does not have to travel if he himself has sufficient video and audio resources locally.

The invention therefore proposes a telecommunications installation with videophone capacity organized to in particular offer an entry option to third parties on established videoconferencing.

The telecommunications installation is of the private and multiservice type, it is attached to a digital network with service integration and it is intended to allow the establishment of communications, in particular videophone type communications between videophone units, called 'user, each associating at least one digital telephone set and video means; these incorporate at least one camera and one monitor.

The installation is equipped with a digital PABX type telephone switch which is connected to the network, a video switch organized around at least one broadband switching matrix, at least one video codec for converting video signals. / analog audio in digital signals and vice versa, this codec is connected to the video switch by analog channel and to the PABX by digital channel.

According to a characteristic of the invention, the installation further comprises a server connected to the PABX, to the video codec and to the video switch by digital links, to ensure the control of this codec and of this switch under the control of the PABX, server is also connected to the video switch by a link allowing the transmission of analog video / audio signals. Each local videophone unit which is connected to the PABX by a digital link serving its telephone set and to the video switch by an analog link serving its video means, includes control means, in particular of the mouse, trackball, tablet type. sensitive or analogous, associated or integrated with a telephone set of the unit to allow a user to control by telephone the establishment of two-way or multidirectional videophone communications.

The invention, its characteristics and its advantages are specified in the description which follows in conjunction with the figure mentioned below.

This single figure presents a block diagram relating to a telecommunications installation, according to the invention, connected to a digital network with integrated services (ISDN).

The telecommunications installation 1 presented in the single figure conventionally comprises a digital PABX type unit with service integration 2, which is connected to an ISDN network referenced 3, through which the various subscribers of the installation, whether dessert switch, can communicate with correspondents outside this installation 1.

A video switch 4 equips the installation 1 to allow the establishment of analog video connections, it is for example constituted by a broadband switching matrix and it is controlled by a server 5 which is itself placed under the control of the PABX 2 or more precisely the control logic of the latter which is provided with software processing means; in the case considered here, this control logic receives requests for videophone actions, or related to videophone, from users.

A processing unit, called QUAD, 6, is connected to the video switch 4 to allow the simultaneous display of several video signals, for example four, in a single image, it is notably used when holding videophone conferences.

At least one codec 7, then centralized, allows the conversion of analog video and audio signals into digital signals and the reverse conversion according to the direction of transmission, outgoing or incoming, of the signals. I1 is connected to the video switch 4 to which it transmits and from which it receives analog video / audio signals, it is also connected to the PABX 2 or more precisely to the switching unit of the latter by one or more digital links, for example links at 64kB / s, and via this PABX to the ISDN network 3.

Telephone auxiliary equipment 8 allows the establishment of a digital telephone type link between codec 7 and the PABX for the exchange of sound type signals with a user telephone or terminal.

A user videophone unit comprises at least one digital telephone set connected to the PABX 2, and video and possibly audio means, constituted at least by a camera and a monitor, connected to the video switch 4, by a video / audio link of the type analog, such are the user videophone units 9A and 9B, respectively consisting of a digital telephone set 9A1 or 9B1, a camera 9A2 or 9B2 and a monitor 9A3 or 9B3. Each videophone unit also includes a control device such as 9All, 9Bll or 9C11, whether or not integrated into the telephone set and connected by the latter's digital telephone link to the PABX 2. The control device is, for example, of the mouse, trackball type. , sensitive tablet or other, it allows commands to be sent to server 5, via PABX 2.

Many additional elements are likely to be added to the minimum user unit defined above, in particular when such a unit, such as 9C, is intended to serve a videoconference room which is then likely to include several 9C1 telephones, several 9C2 cameras, several 9C3 monitors, a 9C4 video recorder, and 9C5 audio equipment, such as microphones and speakers, etc.

The server 5 ensures the interpretation of the orders originating from the PABX 2 by a digital link, following the requests that the local users make via the control devices which they have respectively, as indicated above. I1 therefore controls the video switch 4 and the codec 7 and provides the corresponding human-machine interface.

To this end, it allows the transmission, via the video switch 4, of images for selecting programs or commands intended to be displayed on the screens of the monitors of the users, coming from itself or from a remote server, via codec 7, in the latter case. It is able to interpret the commands triggered by a control device, such as 9A11, available at a telephone set of a videophone unit, in conjunction with the indications provided to users by the selection images provided on a monitor screen. of this unit, for example in the form of video icons embedded in the images displayed.

An installation as envisaged above mainly makes it possible to carry out local video telephony in installation 1 itself, video telephony through the
ISDN 2, and a third party entry of a participant during an established video conference

In the case of internal videophone, a user operates a videophone unit, such as 9A, of the installation 1 to establish an internal videophone connection, through the video switch 4, with a correspondent also having a user unit. , such as for example 9B, also attached to installation 1.

To this end, a call by telephone is launched by the user calling to his correspondent via PABX 2, the latter interprets the call so as to establish a connection between them. The video signals exchanged between the caller and the called party are of analog type and they are transmitted in baseband; the audio signals pass through the telephone link established via the PABX 2 and / or possibly through the video switch 4, if the two correspondents are equipped with microphones and speakers independent of their telephone sets.

The video door entry operations that can be carried out correspond practically to those usually carried out in telephony using a PABX. They allow in particular the warning of a correspondent during a videophone communication, the back and forth between a user and correspondents, the transfer of a communication, the conference between three user videophone units, with the possible insertion of images from an additional video / audio source at the instigation of one of the participants in the mosaics of images displayed on the monitors of these participants, or even the operation as a server or video / audio broadcaster. Incidentally, a possibility of zooming in on one or other of the images making up a displayed mosaic is also made available to participants.

Video calling via ISDN 2 involves the use of a codec 7. For a given video communication, this codec receives from a user unit - the video signal coming from the video means of this local user video unit, via the video switch 4, - the audio signal from the telephone set produced in this videophone unit, this signal being transmitted via the PABX 2 and the auxiliary telephone equipment 8, - possibly the audio signal which comes from an additional microphone of the videophone unit considered and which is transmitted, via video switch 4, with the video signal emitted by this videophone unit.

The requesting user connects to codec 7 by a telephone type dialing action carried out for example on the keypad of a telephone set which he has at his videophone unit.

A telephone connection is then established by and via the
PABX 2 between this station and the auxiliary telephone equipment 8 associated with codec 7, an analog link is also established between the video / audio means of the videophone unit and the codec 7, via the video switch 4.

An image, for example of the menu opening screen type, is then capable of being sent to the screen of the monitor of the calling videophone unit from the server 5.

The control device made available at the level of a videophone unit for sending commands to the server 5, via the PABX 2, makes it possible to trigger the making of a call from a user to one or possibly several external correspondents through the ISDN network 3 to which the PABX has access. This triggering is obtained for example by an action of the user, on the control device, such as 9All, which he has, in relation to the icons or menus and activatable submenus which are then displayed by the user's monitor, under the action of the server 5. The latter is in fact actively connected to the control device concerned by a data transmission channel established between one of the communication ports which it comprises and the telephone set with which the control device is associated , via PABX 2.

Calling a remote party through the
PABX 2 through the ISDN network 3 causes codec 7 to be linked to a remote installation codec, not shown, serving the correspondent, via the network
ISDN 3 and allows the establishment between these codecs of a digital video / audio communication, this connection achievable via the PABX 2, which can possibly be provided directly between codecs via the ISDN 3 network, as indicated in dashed on the figure.

If the codec called serves only a videophone unit in the remote installation which includes it, the incoming call is direct and does not require any additional selection of correspondent.

If the codec called is likely to serve several video door entry units in the remote installation which includes it, a selection must be made.

In one embodiment, it is provided that the server of the remote installation can send to the server 5, a list of subscribers that can be reached through the video telephone units of the users of the remote installation, so that this list is displayed on the monitor of the calling user.

Following the choice made by the latter, the selected correspondent is telephonically notified of the videophone call launched towards him which ends at the telephone set, provided in the user equipment serving him, via the telephone equipment associated with the codec which serves him and which has previously been called, as indicated above.

The response of this subscriber leads to the establishment of the video / audio connections necessary for the establishment of the videophone communication between caller and called.

Each of these possibly has the possibility of controlling the audio / video resources of its correspondent in a manner analogous to that of which it controls its own.

Everyone can possibly have the possibility of carrying out the video / audio warning of their remote correspondent, then the videophone call of another user of the installation to which they belong, or a transfer of the call in progress, or establishing a videoconference ...

A user who has established a videoconference using a user videophone equipment with a remote installation has the possibility of having a correspondent locally enter a third party; the latter can possibly be remote, if the local installation from which the user communicates has at least two codecs.

In the event that the third party to be contacted has a videophone unit belonging to the same installation as that of the user in question, the latter makes a consultation call as in conventional telephony, consequently the remote correspondent with whom he was in communication videophone is put on hold and it receives for example a guard image through in particular the video switch 4, the codec 7 and the remote codec, not shown, serving the correspondent on hold, as well as music on hold emanating from the PABX 2 .

In this case, the internal videophone functions mentioned above are accessible as soon as a videophone connection is established in installation 1.

The user can initiate a conference call between the remote correspondent, the called third party and himself via the control device of the videophone unit that he operates. Each participant in the conference then receives the same images obtained by mosaic association of the images simultaneously produced by the video means of each of the user videophone units that each of them uses respectively.

As indicated above, possibilities for zooming in on an image are possibly provided at least locally, the remote correspondent then receiving only the images that the user sends him to send.

In one embodiment, the optional addition of an additional video / audio source is provided, for example by the user, for the possible benefit of all the participants, who then receive an additional image which is inserted into the displayed mosaic. by the monitors used by these participants.

The user has the possibility of going back and forth between the remote correspondent and the called third party, the third party being in video / audio custody, when the remote correspondent is reconnected visiophonically to the user who initiated the inquiry call.

If the user hangs up his telephone set after having made a consultation call while he was in videophone connection with a remote correspondent, the PABX maintains the videophone connection between codec 7 and the remote codec serving this correspondent and extends it to the third party called during the consultation call, again as in conventional telephony.

In the case where the third party to be contacted has a videophone unit which does not belong to the installation of the calling user, the latter also makes a consultation call as in conventional telephony, which warns the remote correspondent with whom he was already in videophone communication. This remote correspondent then receives guard information from the installation 1, ie in this case a guard image successively transmitted via codec 7 and the remote codec, not shown, which serves him and for example music by guard from PABX 2.

The remote third party, called by the user by telephone during the consultation call phase, is then connected to the calling user through the ISDN network 3 in a manner similar to that provided for the remote correspondent then on hold, the digital video / audio communication being however established in the envisaged embodiment by means of a second codec 7 'and in connection with a second server 5' of the installation 1.

The user is then able to go back and forth between the remote correspondent called first and the remote third party called subsequently, he can also carry out a conference in a manner analogous to that described above.

Claims (2)

1 / Telecommunications installation, of the private and multiservice type, attached to a digital network with service integration (3) and intended to allow the establishment of communications, in particular videophone type communications between videophone units, known as user units , (9A, 9B, 9C, ...) each associating at least one digital telephone set (9A1) and video means, the latter incorporating at least one camera (9A2) and one monitor (9A3), the installation being provided a digital PABX type telephone switch (2) which is connected to the network (3), a video switch (4) organized around at least one broadband switching matrix, at least one video codec ( 7) conversion of analog video / audio signals into digital signals and vice versa which is for this purpose connected to the video switch by analog channel and to the PABX by digital channel, the installation being characterized in that it further comprises u n server (5) connected to the PABX, the video codec and the video switch by digital links, to ensure control of this codec and this switch under the control of the PABX, and connected to the video switch by a link allowing the transmission of analog video / audio signals, and in that each local videophone unit, connected to the PABX by a digital link serving its telephone set and to the video switch by an analog link serving its video means, includes control means (9A11 , 9Bll or 9Cll) associated or integrated with a telephone set of the unit to allow a user to control by telephone the establishment of two-way or multidirectional videophone communications. 2 / Telecommunications installation according to claim 1, characterized in that an auxiliary telephone equipment (8), connected by digital telephone type link to the PABX, is associated with the video codec (7) to allow transmission via the video switch (4) for signals, of the sound type, transmitted digitally from a telephone set (9A1, 9B1 or 9C1) of a videophone unit as well as the reverse direction transmission of the codec to a set 3 / Telecommunications installation, according to at least one of claims 1 and 2, characterized in that the PABX comprises software means suitable for controlling an additional connection, of the third party entry type on a communication or conference established, from a videophone unit in communication, said means, operated from a control device associated or integrated into the telephone set of the videophone unit initiating entry into third parties, acted both at the switching unit of the PABX itself and at the video switch for videophone connections.