Abstract:
A method of establishing a private audio communication channel on an intercom system ( 100 ) having a plurality of intercom units ( 101 - 1  to  101 -n), is diclosed. The intercom system  100  is activated by spoken request data input via at least one of the intercom units ( 101 - 1  to  101 -n). Audio data is transmitted to substantially each of the plurality of intercom units ( 101 - 1  to  101 -n) in response to the spoken request data. A private audio communication channel is established between at least two of the plurality of intercom units ( 101 - 1  to  101 -n) in response to spoken reply data input via any one of the plurality of intercom units ( 101 - 1  to  101 -n).

Description:
FIELD OF THE INVENTION 
     The present invention relates to intercoms and, in particular, to a computer controlled intercom. The invention also relates to a computer program product including a computer readable medium having recorded thereon a computer program for managing a computer-controlled intercom. 
     BACKGROUND 
     Typically intercom systems are not orientated towards ease of use. Most intercoms are merely of a telephony configuration where a calling user must go to an intercom unit and press a button in order to page a person with whom they wish to communicate. The caller&#39;s spoken phrase is then broadcast via a plurality of connected intercom units. The person being paged must then stop what they are doing, proceed to the nearest intercom unit and press a button to establish a communication link with the caller. Each time one of the persons speaks, the button on their respective intercom unit must be depressed. Further, their entire conversation is generally broadcast via the other remaining intercom units which are connected to the system. 
     SUMMARY OF THE INVENTION 
     It is the object of the present invention to ameliorate one or more of the limitations of the intercom systems described above. 
     According to one aspect of the present invention there is provided a method of establishing a private audio communication channel on an intercom system having a plurality of intercom units, said method comprising the steps of: 
     activating said intercom system by spoken request data input via at least one of said intercom units; 
     transmitting audio data to substantially each of said plurality of intercom units in response to said spoken request data; and 
     establishing a private audio communication channel between at least two of said plurality of intercom units in response to spoken reply data input via any one of said plurality of intercom units. 
     According to another aspect of the present invention there is provided an intercom system comprising: 
     a plurality of intercom units each including at least an input means for inputting spoken data; and 
     processor means interconnected with said plurality of intercom units via a communication links wherein said processor means outputs audio data in response to spoken request data received from one of said plurality of intercom units via said communication link, and wherein said processor means establishes a private audio communication channel between at least two of said plurality of intercom units in response to spoken reply data recieved from at least one of said plurality of intercom units via said communication link. 
     According to still another aspect of the present invention there is provided a computer readable medium, having a program recorded thereon, where the program is configured to make a computer execute a procedure to establish a private audio communication channel on an intercom system having a plurality of intercom units, said program comprising: 
     code for activating said intercom system by spoken request data input via at least one of said intercom units; 
     code for transmitting audio data to substantially each of said plurality of intercom units in response to said spoken request data; and 
     code for establishing a private audio communication channel between at least two of said plurality of intercom units in response to spoken reply data input via any one of said plurality of intercom units. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A number of embodiments of the present invention will now be described with reference to the accompanying drawings in which: 
     FIG. 1 is a schematic diagram of an intercom system according to a first embodiment of the present invention; 
     FIG. 2 is a schematic diagram of an intercom system according to a further embodiment of the present invention; 
     FIG. 3 is a flowchart showing the operation of the intercom system in accordance with the embodiments of the present invention; 
     FIG. 4 is a schematic diagram of an intercom system according to still a further embodiment of the present invention; 
     FIG. 5 is a schematic block diagram of a general-purpose computer used in the system of FIGS. 1 and 2; and 
     FIG. 6 shows a block diagram of an intercom unit as used in the intercom system of FIGS. 1,  2  and  4 . 
    
    
     DETAILED DESCRIPTION 
     Where reference is made in any one or more of the drawings to steps and/or features, which have the same reference numerals, those steps and/or features are for the purposes of the description the same, unless the contrary appears. 
     The preferred embodiments provide an intercom system with hands-free voice recognition facilities. These facilities are provided at low cost through the use of a general purpose computer for voice recognition processing. 
     The first embodiment is illustrated in FIG.  1  and takes the form of an intercom system  100  including a plurality of intercom units  101 - 1  to  101 -n being directly linked to a processor unit  104  of a computer system  105  via wired connections  102 - 1  to  102 -n, respectively. Preferably, a Universal Serial Bus (USB) interface is used to interface to the computer system  105 . However, other interface techniques including FireWire,  10 BaseT and  100  BaseT are also possible. 
     The wired connections  102 - 1  to  102 -n are preferably USB wire connections. The USB wire connections preferably carry USB isoc0hronous mode audio data. 
     In another embodiment, as seen in FIG. 2, the intercom units  101 - 1  to  101 -n can be directly linked to a USB audio interface device  207  located near the computer system  105 . In this instance, wired connections  202 - 1  to  202 -n can be connected between the intercom units  101 - 1  to  101 -n and the USB audio interface device  207  to carry analog data. A USB connection  203  between the audio interface device  207  and the processor unit  104  can carry USB isochronous mode audio data. 
     In still another embodiment of the present invention, a radio frequency transceiver device (not illustrated) can be used to connect the intercom units  101 - 1  to  101 -n to the processor  104 . The Bluetooth wireless standard is an example of a suitable wireless connection. 
     FIG. 6 shows a block diagram of the intercom unit  101 - 1  as used in the intercom system  100 . The intercom unit  101 - 1  comprises an audio speaker  601 , an audio microphone  603 , an output line  605  and an input line  607 . The speaker  601  relays any audio signal input to the intercom, via the input line  607 , to a user of the system  100 . The audio microphone  603  detects any call phrases spoken by the user and outputs them to the system  100 , via the output line  605 . 
     The computer system  105  is preferably a conventional general-purpose computer, such as the one shown in FIG.  5 . The computer system  105  comprises a processor unit  104 , input devices such as a keyboard  502  and mouse  503 , output devices including a printer  515  and a display device  514 . A Modulator-Demodulator (Modem) transceiver device  516  is used by the processor unit  104  for communicating to and from a communications network  520 , for example connectable via a telephone line  521  or other functional medium. The modem  516  can be used to obtain access to the Internet, and other network systems, such as a Local Area Network (LAN) or a Wide Area Network (WAN). 
     The processor unit  104  typically includes at least one processor  505 , a memory unit  506 , for example formed from semiconductor random access memory (RAM) and read only memory (ROM), input/output (I/O) interfaces including a video interface  507 , and an I/O interface  513  for the keyboard  502  and mouse  503  and optionally a joystick (not illustrated), and an interface  508  for the printer  515  and the modem  516 . A storage device  509  is provided and typically includes a hard disk drive  510  and a floppy disk drive  511 . A magnetic tape drive. (not illustrated) may also be used. A CD-ROM drive  512  is typically provided as a non-volatile source of data The components  505  to  513  of the processor unit  104 , typically communicate via an interconnected bus  504  and in a manner which results in a conventional mode of operation of the computer system  500  known to those in the relevant art. Examples of computers on which the embodiments can be practised include IBM-PC&#39;s and compatibles, Sun Sparcstations or alike computer systems evolved therefrom. 
     FIG. 3 is a flowchart showing the operation of the intercom system  100  in accordance with the embodiments of the present invention. The intercom system  100  is configured so that a user can activate the system  100  by speaking a request phrase. The processor unit  104  preferably comprises a voice recognition module stored in the memory  506 . For example, The Microsoft™ Speech Software Development Kit is a suitable voice recognition module. The process begins at step  301 , where the intercom system  100  is activated by the user speaking the request phrase into one of the intercom units  101 - 1  to  101 -n. The request phrase spoken by the user preferably contains the name of a person that the user wishes to communicate. At the next step  303 , the request phrase is preferably received and recognised by the processor  505  which signals the remaining intercom units to re-broadcast a call phrase containing the name of the person being called. Preferably, the re-broadcasted call is a pre-recorded announcement, whereby the called person&#39;s name is inserted by the processor  505  at a particular point in the announcement, For example, the pre-recorded announcement may be “Paging Name, Paging Name”, where the called person&#39;s name can be inserted by the processor  505 . The pre-recorded announcement can be stored in the memory  506  or storage device  509  of computer system  105 . In accordance with the example, if the request phrase spoken at step  301  was “calling John Citizen”, then the processor  505  would insert the name John Citizen such that the announcement “Paging John Citizen, Paging John Citizen” would be broadcast via the remaining intercom units. Alternatively, the processor  505  can record the request phrase as spoken by the user and replay the request phrase as the re-broadcasted call phrase. The process continues at step  305 , where after re-broadcasting the call phrase the remaining intercom units preferably listen for an answering response. At the next step  307 , the intercom units  101 - 1  to  101 -n relay any received response to the processor unit  104  and the processor  505  decides which of the remaining intercom units can hear the response most clearly by comparing audio signals from the remaining intercom units. Therefore, the intercom unit with the greatest audio signal is selected. The process continues at step  309 , where the selected intercom unit is signalled by the processor  505  and a private two-way audio connection is set up between the selected intercom unit and the intercom unit (hereinafter “originating intercom unit”) which initially received the spoken request phrase. The other remaining intercom units preferably no longer participate in the communication once the two-way audio connection has been set up. The process concludes at step  311 , where a close of connection signal is received by the processor  505  and the connection between the chosen intercom unit and the originating intercom unit is shut down. The close of connection signal can be sent by either of the participating intercom units and is signalled by a predetermined period of silence from either of the participating intercom units. 
     Preferably, the processor unit  104  can monitor the audio received from the remaining intercom units after the two-way audio connection has been set up between the chosen intercom unit and the originating intercom unit. In this instance, as and if the audio signal from one of the other remaining intercom units becomes clearer than the audio signal from the currently participating intercom units, audio input will be taken from the clearer intercom unit instead. Preferably, a second two-way audio connection can be set-up between two different users whilst the initial two-way audio connection is being carried on, in accordance with the preferred embodiment of the present invention. In the instance that a second connection is set-up, the two intercom units participating in the first connection will not be involved in the second connection at all. 
     In still a further embodiment of the present invention an intercom system  400  is provided, which comprises a master intercom station,  401  connected to a plurality of other intercom units  402 - 1  to  402 -n, as shown in FIG.  4 . The master intercom station  401  is preferably directly connected to a plurality of other intercom units  402 - 1  to  402 -n, via wires  403 - 1  to  403 -n. Alternatively, a wireless connection, such as that provided by the Bluetooth standard, or any combination thereof can be used to connect the master intercom station  401  to the plurality of other intercom units  402 - 1  to  402 -n. The master intercom station  401  preferably contains sufficient processing capability to perform speech recognition functions and bi-directional audio channel functions. The master intercom station  401  preferably comprises a voice recognition module stored in a memory (not illustrated) located within the master intercom station  401  and a processor (eg. the processor  505  of FIG.  5 ). The master intercom station  401  preferably also contains additional custom software to carry out the following functions in accordance with the above-described embodiments of the present invention: 
     (i) listen for activating request phrases from all intercom units  402 - 1  to  402 -n; 
     (ii) re-broadcast a call phrase to all intercom units  402 - 1  to  402 -n; 
     (iii) listen for a response of a prescribed form; 
     (iv) route bi-directional audio data between a chosen intercom unit and the originating intercom unit; and 
     (v) detect a close of connection signal from either of the chosen intercom unit and the originating intercom unit. 
     The operation of the intercom system  100  in accordance with the embodiments and as shown in FIG. 3, is preferably implemented as software executing on the computer system  105 . In particular, the intercom system  100  software can be hosted under Windows™. Windows™ is advantageous since it provides many ancillary features such as plug-and-play installation, hard disks and file systems, network interfaces, scalable fonts, etc. It is important to note that all computation is performed by the processor unit  104  or master intercom station  401 . 
     The software is preferably divided into two separate parts; one part for carrying out the processor unit  104  applications; and another part for performing the intercom functions described above. The software is stored in a computer readable medium, including the storage devices described above, for example. The software is loaded into the computer system  105  from the computer readable medium, and then executed by the computer system  105 . A computer readable medium having such software or computer program recorded on it is a computer program product. The use of the computer program product in the computer preferably effects an advantageous apparatus for interacting with the intercom system  100  intercom units in accordance with the embodiments of the invention. 
     Typically, the application program of the preferred embodiment is resident on the hard disk drive  510  and read and controlled in its execution by the processor  505 . Intermediate storage of the program and any data fetched from the network  520  may be accomplished using the semiconductor memory  506 , possibly in concert with the hard disk drive  510 . In some instances, the application program may be supplied to the user encoded on a CD-ROM or floppy disk and read via the corresponding drive  512  or  511 , or alternatively may be read by the user from the network  520  via the modem device  516 . Still further, the software can also be loaded into the computer system  500  from other computer readable medium including magnetic tape, a ROM or integrated circuit, a magneto-optical disk, a radio or infra-red transmission channel between the computer module  501  and another device, a computer readable card such as a PCMCIA card, and the Internet and Intranets including e-mail transmissions and information recorded on websites and the like. The foregoing is merely exemplary of relevant computer readable mediums. Other computer readable mediums may be practiced without departing from the scope and spirit of the invention. 
     Voice recognition is one of the important aspects of the intercom system  100 . The processor unit  104  or the master intercom station  401  recognises the name of the person included in the request phrase and selects that name from a library of names for re-broadcasting. The library of names for re-broadcasting can be stored in the memory unit  506  or storage device  509 . Voice activation has been shown to be feasible in constrained problem spaces, where the context constrains what can be done, and thus helps to guide interpretation. The intercom system  100  preferably does not use natural language parsing, but instead uses specific key phrases, such as the paged person&#39;s name, to drive interaction. 
     The intercom system  100  can alternatively be implemented in dedicated hardware such as one or more integrated circuits performing the functions or sub functions of FIG.  3 . Such dedicated hardware can include graphic processors, digital signal processors, or one or more microprocessors and associated memories. 
     The foregoing describes only a number of embodiments of the present invention, and modifications, obvious to those skilled in the art, can be made thereto without departing from the scope of the present invention. For example, the intercom units  101 - 1  to  101 -n can include a video monitor (not illustrated) so that a video link can be established between the selected intercom unit and the originating intercom unit, along with the audio connection.