WO1996026609A1

WO1996026609A1 - A dedicated system for audio and video signal bidirectional communication

Info

Publication number: WO1996026609A1
Application number: PCT/EP1996/000717
Authority: WO
Inventors: Alessandro Bellini; Marco Guarducci; Franco Pirri
Original assignee: Hi-Cube S.R.L.
Priority date: 1995-02-22
Filing date: 1996-02-20
Publication date: 1996-08-29
Also published as: ITMI950323A0; IT1275243B; ITMI950323A1

Abstract

A dedicated system for the bidirectional communication of audio and video signals, connectable to a plurality of communication systems, both local and remote, and able to be interfaced to a plurality of devices for the acquisition and reproduction of video and sound signals. The system includes: an interface block (120) for communication line connection (L); a coding/decoding block (130) for data compression and expansion, such block being connectable to audio and video peripheral devices; a programmable central processing unit (100) for system control; a memory (110) for storing data and programs for the proper working of the system; and means (190) for inputting commands from the user.

Description

Description A DEDICATED SYSTEM FOR AUDIO AND VIDEO SIGNAL BIDIRECTIONAL COMMUNICATION

Technical Field

This invention refers to a dedicated system for the bidirectional communication of audio and video signals. The system is able to connect to many communication systems, both local and remote, and interfaces many audio and video acquisition and reproduction devices.

More specifically, the invention relates to a dedicated system for bidirectional audio and video signals communication over a generic communication system, which can interface the most common devices for the acquisition and reproduction of video and sound.

The invention is well adapted to transfer audio and video signals to implement videoconferencing and similar user- to-user communication services. Background Art

For videocommunication purposes there are actually known two main categories of systems: the so-called videophone (VT) and a purposely equipped computer, hereinafter named Multimedia Computer (CM) .

The existing VT systems run videophone funtions between human operators who must use a telephone keyboard to input the number of the VT apparatus to which they intend to connec . These VT systems are normally realized as a unitary system and use a telephone ISDN line as communication means. Another limitation of the VT systems is that audio and video signals can be generated and enjoied in real time only.

The existing CM systems normally uses input and output devices typical of computers, and generally they cannot be connected to other reproduction and visualization devices eventually already available at the user's site.

Moreover, conventional CM systems usually visualize their output onto a configurable window on the output device, which nevertheless is smaller of the available screen, and require input commands from a keyboard. Finally, the known CM systems requires hardware and software installation procedures.

Other particular videocommunication systems are disclosed for example in DE-A-3 607 270 which describes a videophone terminal equipped with a display, a TV camera for the pickup of the person and a second camera for the pickup of documents, both mounted on orientable arms, and in JP-A- 4213989 which relates to a videophone communication system provided with an automatic answering unit. Objects of the Invention

It is an object of the present invention to overcome the limitations and drawbacks of the above mentioned prior art, and in particular to provide a dedicated and pre-configured system, capable of (eventually) using audio and video apparatuses already available by the user, and capable to be connected to several different types of communication lines, preferably of the high speed type. Disclosure of the Invention

The invention fulfills these goals by means of a dedicated system for bidirectional communication of video and audio signals, charactherized by comprising:

- an interface block for linking the system to at least one communication line;

- a coding/decoding block connected with one end to said interface block to compress and expand data, and connected with the other end to audio and video peripheral devices,-

- a central processing unit or programmable CPU for controlling the whole system;

- a memory for storing programs and data needed to the working of the system; and

- means connected to the central processing unit to input commands from the user. Additional advantageous characteristics are claimed in the depending claims.

The system of the invention is not limited to application to audio and video signal transmission, but rather it is adapted to accomplish communication management and control functions. The management functions regard - without being limited to - number composition, session start and session end, free and busy functions. The control functions regard - without being limited to - input and output transmission speed toward and from the communication system, the levels of sound, video contrast, color and luminosity.

The system according the invention can be connected to local area networks such as Ethernet or Token Ring, to metropolitan area networks such as ATM, SMDS, Frame Relay and QPSX, and to wide area networks X.25, ISDN, GSM (mobile wireless) and to any telephone network, either switched or dedicated.

Moreover the system of the invention provides for the simultaneous and/or the alternative connection to a wireless remote command for managing the communication, to a telephone apparatus, a microphone, a loudspeaker, a TV camera, a monitor, a domestic TV, a headset, an integrated headset/micro, a hands-free phone unit.

The system of the invention additionally allows for videocommunication functions such as, for example, an automatic answering function for remote surveillance or monitoring, local record and reproduction of video and audio signals by means of either standard analog video recorders or by means of fast digital memory devices, in case of pre¬ recorded signals sent to the remote party, either automatically or at user's command.

The invention will now be disclosed with more details with reference to preferred but non-limiting embodiments thereof, illustrated in the attached drawings in which the same references are used for indicating equal or substantially equivalent components. In the drawings: Brief Description of the Drawings

Fig. 1 shows the general structure of the system, according to the invention, from an outside point of view; and

Fig. 2 is a block diagram which illustrates the general structure of the system according to the invention.

Referring to the Figures, and in particular to Figure 2, the system according to the invention comprises a hardware programmable system, which includes a number of blocks or main units.

The system of the invention is connected or linked to the outer world, i.e to an communication line L, throgh a bidirectional interface block 120. This interface block normally includes two or more interfaces, for example a block 121 to interface an Ethernet network, a block 122 to interface a Token Ring network, a block 123 to interface X.25 network, a block 124 to interface a plain telephone line both, switched or dedicated, a block 125 to interface a GSM line, a block 126 to interface an ATM line, a block 127 to interface a QPSX network, a block 128 to interface a Frame Relay line, and a block 129 to interface an ISDN line.

The system of the invention can exploit the whole capabilities of the communication lines including one-to-many communication. As a consequence the system of the invention can operate in the so-called multicast mode, i.e. one user can trasmit audio and video signals to many users at the same time. This feature is not currently available on existing VT systems without employing an external multiconferencing unit (MCU) . Another important consequence is that the system of the invention allows the user to communicate on networks such as Internet or any other IP-based network.

The interface block 120 is connected as input/output to a block 100 for performing data reception and transmission. Block 100 is a programmable Central Processing Unit (CPU) which manages the whole system by using a specific software. The CPU is connected to a block of memory 110 which contains all the programs and data necessary to the system proper working .

The system further provides a coding/decoding block (Codec) 130 to compress output data and to expand input data. This block includes three sub-blocks: a sub-block 131 for interfacing external audio and video signals - preferably through a SCART connector - to a plain television apparatus, a sub-block 132 to interface a TV camera CA as input (I) and a plain video monitor MN as output (0) , for example a computer video monitor, and a sub-block 133 to interface a microphone M as input and a loudspeaker LS as output. Moreover, block 130 is preferably provided with one or more connectors for audio and video signals, and several additional devices can be managed by the CPU 100, for example a printer, an external memory etc, all connected to block 130.

The block 130 is controlled by the CPU 100 which, by running a proper software, carries out all the requested transformations for transferring information from and to the connected interface block 120.

The system further includes one or more internal interfaces that are illustrated hereinbelow.

A block 140, connected to the CPU, builds up an interface for a wireless remote control (or command) , preferably an infrared remote control (IRT) device. Since the operation of this block is well-known, it is not furher described here, but for pointing out that it provides for receiving indications to manage the communication and to control speed, sound loudness, contrast, luminosity levels and the like.

A local console, indicated at 150, is made up by a sub- block 151, comprising a local keyboard, and by a sub-block 152, which is a remote or local digital display. Block 150 is connected to the CPU and allows all control and management functions to be accomplished by the system of the invention, without requiring any additional external component, such as the above mentioned remote control or an external telephone set. If desired, block 150 is connected to the CPU, which receives user's commands from the keyboard 151. After eventually translating and executing the user's commands, the CPU can visualise results and error messages on display 152.

A block 160 for interfacing a plain telephone set can be provided both for managing the communication and for the audio signals input and output. The block 160 is connected to the CPU 100, which performs all signalling and controls, and to transform input and output audio signals. Typically, block 160 can be used to establish a phone conversation with conventional telephone subscribers, i.e. users who are equipped with a conventional telephone apparatus, while at the same time taking advantages of all the other possibilities allowed by the system of the invention, such as a hands-free operation, the remote control and so on.

Therefore the system according to the invention is also equipped with an internal interface (190 in Fig. 2) for inputting command and control signals.

In addition the system can include a block 170 aimed at interfacing the CPU to a device referenced as H+M and comprising an earphone and a microphone. Of course, such block 170 might even interface an earphone only, without the microphone. Still in relation to block 170, the CPU 100 is responsible to acquire and properly transform (convert) the audio signals both in input and output.

Block 180 interfaces the system according to the present invention to a W unit, known as hands-free unit. In relation to block 180, the CPU 100 is also responsible for acquiring and transforming the audio signals both in input and output.

The system may be implemented according to ordinary and currently available hardware and software technologies, on one or more printed circuit boards, in case interconnected through a bus. One possible implementation comprises electronic modules available on the market of parts and boards for Personal Computers (PC) . Blocks 100 (CPU) , 110 (memory) and the bus may accomplish functions equal or similar to those of the PC motherboards in accordance with the standard MPC2.

Each sub-block composing block 120 may correspond to one or more PC bus boards suitable for the motherboard standard. In the same way it is possible to find on the market the Codec block 130 as well as the other blocks 140, 150, 160, 170, 180 for interfacing to I/O audio and video devices.

Power supply block 200 supplies the required voltages to the system from the public RN line or from a local battery.

The system behaviour is now briefly described.

Suppose that two systems according to the invention are to be interconnected through a generic digital network chosen from those listed above. This is only an exemplary conventional configuration to highlight how the system works without any limiting meaning to the scope of the invention. The two interconnected systems are respectively named local and remote system.

The user connected to the local system can call the user connected to the remote system by sending a signaling acquired by one of the local blocks 140, 150 and 160. Once received, the signaling is interpreted by local block 100 and transformed into a message that is forwarded to local block 120. Local block 120 sends the message to the remote block 120 through the digital line.

The remote system receives the message from the remote user's block 120 and the message is then transferred to the remote CPU. The remote CPU signals the remote user through blocks 130,150, 160, 170 and/or 180. Alternatively the remote system may automatically respond if programmed to work in such a manner.

When the remote user is urged to respond, he/she may choose to answer. Let's assume the remote user decides to answer. The local system gets the video signal from camera 132, and audio signal from one (or more) among blocks 130, 160, 170 and/or 180. The local CPU block 100 transforms video and audio signals and sends them through block 120 to the digital line. At the same time, the local system gets from the digital line - through the block 120 - audio and video data coming from the remote system. The incoming audio and video data are forwarded to the local CPU block 100, transformed by this CPU block and routed to blocks 130, 160, 170 and/or 180. The reciprocal process takes places on the remote system during an audio-video session.

The session is ended when one of the two users issues an end session command through the blocks 140, 150 and/or 160.

Regulations and adjustments may always be accomplished in the system according to the invention both in idle, signaling and transmitting modes.

As above mentioned, the system is preferably equipped with a software program (stored in memory 110) . This software program is divided in two main modules: a control module and an action module.

The control module is aimed at getting user commands, and to automatically answer, if it is so programmed.

Commands are devoted to signaling and regulation. In fact, the control module has to acquire commands from blocks 140, 150 and/or 160, and to interpret those commands to be executed. Signaling commands generally produce messages to be sent to the digital line.

Regulation commands are generally translated in corresponding commands for local I/O audio and video equipment. The only exception is the transferring speed on a digital line.

The actions to be executed are the following:

- data transmission/reception to and from the digital line, according to a procedure specified in the sub-blocks of interface block 120; - audio data acquisition from blocks 130, 160, 170 and/or 180;

- audio data delivery toward blocks 130, 160, 170 and/or 180;

- video data acquisition from camera through block 132;

- video data delivery toward blocks 131 and/or 132;

- redirection and transformation of the data video stream from block 132 to block 120, and from block 120 to block 131 and/or 132.

Industrial Applicability

The invention is applicable in telecommunication transmission systems and in particular for bidirectional audio and video signals communication over a generic communication system.

Although the invention has been described with reference to specifical embodiments, the same is not limited to what has been disclosed, but the invention is extended to cover all possible changes and/or modifications that will be evident the the skilled in the art in view of the present description.

Claims

1. A dedicated system for bidirectional communication of video and audio signals, characterized by comprising:

- an interface block (120) for linking the system to at least one communication line (L) ,^•

- a coding/decoding block (130) connected with one end to said interface block (120) to compress and expand data, and connected with the other end to audio and video peripheral devices;

- a central processing unit or programmable CPU (100) for controlling the whole system;

- a memory (110) for storing programs and data needed to the working of the system,- and

- means (190) connected to the central processing unit (100) to input commands from the user.

2. A system as claimed in claim 1, charactherized in that said means (190) to input commands includes a wireless remote control interface (140), such as an infrared remote control device (IRT) .

3. A system as claimed in claim 1, characterized in that said means (190) to input commands includes a local console

(150) .

4. A system as claimed in claim 3, characterized in that said local console (150) includes a local keyboard sub-block

(151) and a display or local visualizer (152) .

5. A system as claimed in claim 1, characterized in that said means (190) to input commands includes a telephone (T) interface ( 160) .

6. A system as claimed in any of the preceding claims, characterized in that said coding/decoding block (130) includes: an audio and video block (131) to interface a television set (TV) ; a sub-block (132) to interface an input (I) to a camera (CA) and to interface an output (0) to a monitor (MN) ; a sub-block (133) to interface a microphone (M) in input and a loudspeaker (LS) in output.

7. A system as claimed in any of the preceding claims, characterized in that said interface block (120) includes at least one of the following: a block (121) to interface with an Ethernet network, a block (122) to interface with a Token ring network, a block (123) to interface with a X.25 network, a block (124) to interface with an ordinary telephone line, switched or dedicated, a block (125) to interface with a GSM line, a block (126) to interface with an ATM line, a block (127) to interface with a QPSX line, a block (128) to interface with a Frame Relay line, a block (129) to interface with a ISDN and B-ISDN line.

8. A system as claimed in any of the preceding claims characterized in that there it provides for another block (170) to interface with a set composed of an earphone and a microphone (H+M) .

9 . A system as claimed in any of the preceding claims , characterized in that it provides for another block ( 180 ) to i nt erf ac e wi th an hands - f ree uni t ( VV ) , to a cqu i re and transform input and output audio signals .

10 . A system as claimed in any of the preceding claims , characterized in that said coding/decoding block (130) can be connected to a printer and/or other storage unit.

11. A system as claimed in any of the preceding claims, characterized in that said coding/decoding block (130) includes a SCART connector for connection to a television set (TV), and a set of connectors for audio or data signals.

12. A system as claimed in any of the preceding claims characterized in that it can operate on networks supporting multicast communication, thus allowing one-to-many communication.

13. A system as claimed in any of the preceding claims, characterized in that it can operate on Internet.