Abstract:
A network based conference system is disclosed for allowing providing image access to remote attendees. The network based conference system includes an image acquisition module which communicates with a collaboration server over a network. Remote attendees may readily monitor an ongoing presentation in near real-time via a network connection to the collaboration server. According to one embodiment of the invention, the remote attendees may monitor the ongoing presentation via the use of a standard Internet browser. The network based conference system is particularly useful for overcoming the requirements of installation and operation of special conferencing software and hardware of network conference systems known in the art.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to a network based conference system and is particularly concerned with providing remote conference participants network access to ongoing presentations in near-real time.  
       BACKGROUND OF THE INVENTION  
       [0002]     For many years overhead projectors have been popular for providing a display suitable for viewing by a group of meeting attendees. A set of prepared transparencies (also known as a slide deck) are placed upon a projector apparatus and a magnified image is projected upon a viewing screen. Software, such as Microsoft&#39;s™ PowerPoint™, simplified preparation of polished presentations.  
         [0003]     Subsequent advances in electronics yielded electronic projectors which connect directly to a computer and are electronically driven, for example with a VGA signal, with media content. The displays use the media content to modulate the light and present either a color or black-and-white image on the display screen. The projectors come in different configurations, but typically use a spatial light modulator such as a liquid crystal device to modulate the projected light. Direct connection to a computer video port allows more sophisticated presentations, including animation and video effects. Many portable computers, especially laptop and notebook computers, are provided with a video signal output port. This port is normally used to connect the device to a larger display device than is built in to the portable computer, such as a CRT or flat panel display configured as a docking station.  
         [0004]     An obvious shortcoming of such presentation devices is that meeting attendees must be physically present to view the projected display. Remotely located potential participants face a number of problematical choices. These include joining the meeting via telephone conference, thus missing the visual components of the presentation. Alternately, they could travel to the meeting, with the attendant difficulties of travel time and costs, as well as scheduling. Videoconferencing is yet another alternative that has been developed to assist the remote attendee, but has attendant equipment procurement and training costs, as well as requiring costly high bandwidth connections between videoconferencing sites.  
         [0005]     The advent of the Internet provided an additional venue for conferencing means. Internet video conferencing software has been developed which allows meeting attendees to experience real-time video conferencing between users running a software application on their personal computers. More sophisticated applications, such as PlaceWare&#39;S™ web based virtual conference system, or Microsoft&#39;s™ Exchange Conferencing Server and NetMeeting™ utilize a remote server to host a virtual meeting between attendees.  
         [0006]     Limitations with these virtual conferencing applications include the necessity of installation of new software on an attendee&#39;s computer, with the attendant security concerns for the IT department of the attendee&#39;s organization; and the necessity of the attendee learning how to run the new software. There are also the considerations of operating system compatibility across, for example, Windows™ and Linux platforms, for the new software, and similarly potential hardware limitations across hardware platforms such as Macintosh™, Sun™, HP™ and SGI™. Additionally, the video cameras required to obtain the visual images present their own associated hardware and software interface complexities.  
         [0007]     In view of the foregoing, it would be desirable to provide a technique for allowing a remote attendee to view a meeting presentation in real time which overcomes the above-described inadequacies and shortcomings.  
       SUMMARY OF THE INVENTION  
       [0008]     An object of the present invention is to provide an improved network based conference system.  
         [0009]     According to an aspect of the present invention there is provided an apparatus for providing near real time image conferencing from a video signal output from a computer. The apparatus has an input port for connection to the video output of the computer and an image digitizing module, connected to the input port, for receiving a signal from said input port and constructing a digital image therefrom. Further, the apparatus has a controller module, connected to the image digitizing module for generating a compressed representation of a digital image received from the image digitizing module. Finally, the apparatus has a network interface module connected to the controller module, for transmission of the compressed representation to a network device.  
         [0010]     Conveniently the controller module is a computer having a driver interface module for communication with the image digitizing module, an image compression module for formatting an image obtained from the image digitizing module and a network process module for providing network protocol functions. The computer also has a network interface driver module for communication with the network interface module.  
         [0011]     Various alternatives of the invention have the network interface module alternatively having a modem for transmission over a telephonic network, or having a network interface card for transmission over a digital connection, or an infrared or wireless interface card for transmission over an infrared or wireless connection respectively.  
         [0012]     In accordance with another aspect of the present invention there is provided a system for providing near real time image conferencing from a video signal output from a computer across a network. The system has an image acquisition apparatus connected to said network, wherein the image acquisition apparatus has an input port for connection to the video output of the computer; an image digitizing module connected to the input port, for receiving a signal from the input port and constructing a digital image therefrom; a controller module, connected to the image digitizing module, for generating a compressed representation of a digital image received from said image digitizing module; and a network interface module connected to the controller module, for transmission of the compressed representation to the network. The system also has a collaboration server connected to the network for receiving the compressed representation wherein said collaboration server further formats said compressed representation for viewing.  
         [0013]     Advantages of the present invention include the lack of a need for custom software at the presenter&#39;s computer, or at a remote participant&#39;s computer. The video imagery present upon the presenter&#39;s computer is automatically made available at the collaboration server. Remote participant&#39;s need only access the collaboration server, for example with a web browser if the server is connected to the Internet, to view the conference video proceedings. Joining an ongoing presentation may advantageously be as simple as clicking a hyperlink address. In addition, further advantages may be found in additional functioning supported by the collaboration server including authentication and authorization of meeting participants, maintaining multiple simultaneous meeting image streams, and billing and archival functions.  
         [0014]     According to yet another aspect of the invention, there is provided a method for providing near real time image conferencing from a video signal output from a first computer across a network to a second computer. The method has a first step of establishing a video connection between the first computer and an image acquisition apparatus. The image acquisition apparatus has an input port for connection to the video signal output from the first computer; an image digitizing module, connected to the input port, for receiving a signal from the input port and constructing a digital image therefrom; a controller module, connected to the image digitizing module, for generating a compressed representation of a digital image received from the image digitizing module; and a network interface module connected to the controller module, for transmission of the compressed representation to the network. The next step is that of connecting the network interface module of the image acquisition apparatus to the network. Another step is that of establishing a collaboration server connected to the network for acting as an image dissemination point. Then communication is established between the image acquisition apparatus and the collaboration server across the network, thereafter the image acquisition apparatus commences transmitting the compressed representations to the collaboration server. The collaboration server subsequently reformats the received compressed representations. Next, between the second computer establishes a connection to the collaboration server across said network; and the collaboration server provides the reformatted compressed representations to the second computer.  
         [0015]     The present invention will now be described in more detail with reference to exemplary embodiments thereof as shown in the appended drawings. While the present invention is described below with reference to the preferred embodiments, it should be understood that the present invention is not limited thereto. Those of ordinary skill in the art having access to the teachings herein will recognize additional implementations, modifications, and embodiments which are within the scope of the present invention as disclosed and claimed herein. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]     The invention will be further understood from the following detailed description of embodiments of the invention and accompanying drawings in which:  
         [0017]      FIG. 1  is a pictorial diagram of an electronic projector used in the prior art.  
         [0018]      FIG. 2  is a pictorial diagram of a network based conference system according to an embodiment of the invention.  
         [0019]      FIG. 3  is a block diagram of an image acquisition module according to an embodiment of the invention.  
         [0020]      FIG. 4  is a block diagram of a routine for providing a network based conference according to an embodiment of the invention. 
     
    
       [0021]     In the following description, like reference numbers refer to similar components.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0022]     Referring to  FIG. 1  there may be seen the presentation projection components of a typical meeting as presently practiced in the art. Computer  100 , in this example portrayed as a laptop computer, connects to projector  102  via an interface cable  104 . The interface cable  104  connects to a video output port, not shown, of the computer. Video output ports are well known in the art and typically used to connect a laptop computer to a separate display such as a CRT or flat panel display. In the case of the projector  102 , the video output is transformed into an optical image for projection, indicated by dashed lines  108 , upon presentation screen  106 . The net result is that meeting participants may view the contents of the screen of the computer  100 , typically a prepared presentation, upon the display screen  106  as indicated at image  110 .  
         [0023]     Referring to  FIG. 2  there may be seen the presentation projection components of a network based conference system according to an embodiment of the invention. Computer  200  containing a presentation desired to be shared among meeting participants connects to projector  202  via interface cable  204 . Projector  202  transforms the video signals received via interface cable  204  into optical images and projects them as indicated at  208  upon presentation screen  206 , where the resultant images  210  are visible by the meeting participants. In addition, image acquisition module  220  connects to a video output port of computer  200  via interface cable  224 . In practice computer  200  may have two video output ports, or interface cables  204  and  224  could be constructed as a forked cable should computer  200  have but a single video output port. Image acquisition module  220  performs a “snapshot” of the image constituted by the video signals, formats the resultant image, and transmits the resultant formatted image over network  230  to collaboration server  240 . Note that image acquisition module  220  is connected to network  230  over network connection  238 . This network connection may be as simple as a direct cable, or via other means such as infra-red or wireless connection. Under some circumstances the connection may be to a WI-FI network. The formatting performed by the image acquisition module typically involves image compression and may further involve further processing related to network transmission, for example encapsulation for security purposes. Upon the completion of a snapshot, image acquisition device  220  will perform a subsequent snapshot, format it, and transmit it to collaboration server  240 , the net result of which is a succession of images—an image stream, which matches the images presented upon presentation screen  206  in near real-time.  
         [0024]     Collaboration server  240  receives the image, reformats it, and makes the image available for viewing. Remote participants  250  and  260 , connected to network  230  via network connections  258  and  268  respectively, access the images at collaboration server  240 , and are thus able to view the presentation images, thus allowing visual participation in the ongoing presentation. According to one possible use of the system, meeting participants could join a meeting via an audio-bridge via the telephone network, and in parallel view the ongoing presentation on their respective computer screens.  
         [0025]     In conjunction with presenting the images, collaboration server  240  may carry out a variety of additional functions related to conference networking. Examples of such functions in relation to participants include authentication of would-be meeting participants, authorization of participants, and billing functions. In relation to image acquisition module  220 , collaboration server  240  may perform signalling communication functions in relation to image transmission speed, image compression type used, and ongoing control and adaptation according to network signalling conditions. Other contemplated functions which may be performed at the collaboration server  240 , or by the collaboration server  240  and other network devices include meeting scheduling, recording, archival, and playback functions.  
         [0026]     According to one embodiment of the invention, collaboration server  240  formats the received succession of images from image acquisition module  220  so that they may be accessed and viewed by standard Internet web browser software. This will typically involve referencing the images from a formatted web page. The remote meeting participants link to the web page via a previously established web address. According to one possibility, the address could be communicated in the meeting invitation or agenda as a hyperlink. Also contemplated during the initial linking to the established meeting web page is a series of security transactions. According to one embodiment, a particular meeting or presentation is distinguished by a particular meeting code, similar to a personal identification number (PIN). In this embodiment, the presenter operating computer  200  and the remote meeting participants can use the meeting code number, either at the initial point of communication with collaboration server  240 , or during ongoing communications in order to correctly access the appropriate image stream. This meeting code number could be coordinated among participants prior to the meeting, perhaps using email or some similar notification method.  
         [0027]     It is important to note in  FIG. 2  that projector  202  and ancillary equipment are not necessary to operation of the network conference system in the case where a presenter wishes to convene a meeting of people solely over a network.  
         [0028]     Referring to  FIG. 3 , there may be seen details of a contemplated embodiment of an image acquisition module  320 . Serving as a connection point to image acquisition module  320  is video input connector  322 . This is the connection point for the video interface cable which connects to the computer holding the presentation. Contemplated as an option for some embodiments of the invention is ganged video port  324 , shown in dashed outline, which provides an advantageous daisy-chaining point for another video interface cable. This connector would be used in a presentation arrangement as shown in  FIG. 2  where a connection could be established between the computer  200  of  FIG. 2  and the image acquisition module at video input connector  322 , and then connected to the projector  202  of  FIG. 2  via an interface cable from video connector  324 . Such an arrangement precludes the need for special forked cables, or double video output terminals on computer  200 .  
         [0029]     Returning to  FIG. 3 , the signal received on video input connector  322  connects to image grabber module  370 . This module serves to “grab” the image constituted by the video signal, taking the desired snapshot. This module may have the image grabbing function performed by an off-the-shelf PCI card, or a chain of off-the-shelf devices such as a VGA-to-Video converter and Video-grabber PCI card, or a custom circuit board assembly built from off-the-shelf integrated circuits such as the CYPRESS™ EZ-USB FX USB controller and AD9884A frame grabber. The image grabber module  370  interfaces to the controller module  380 . This module is typically composed of a computer system having a CPU, memory, and ancillary support hardware as is known to those skilled in the art. To minimize heat, noise and power consumption, the controller module would typically be implemented using low power consumption circuitry, for example a processing unit based upon the VIA™ system of processor chips.  
         [0030]     Within the controller module  380  are a number of functional modules, typically implemented in software. These include driver interface module  382  for retrieving images from image grabber module  370 , image compression module  384 , which uses standard compression and formatting algorithms such as JPEG or GIF to compress and format the grabbed images, networking process module  386  typically containing a TCP/IP Network stack and HTTP library and associated functions, and network interface driver module  388  which contains the appropriate functions for connection to and control of network interface module  390 .  
         [0031]     Network interface module  390  provides the connection between the image acquisition module  320  and the network. This module may be a modem for providing connectivity over a telecommunications network, a network interface card for providing connectivity to a local area network, or alternatively an infrared or wireless apparatus. In the case of a physical connection, output connector  328  provides a connection point for an interface cable connecting the network interface module  390  to a network.  
         [0032]     The apparatus described could be used in one particular implementation wherein the video signalling used is a VGA signal as follows with reference to  FIGS. 2 and 3 . The presenter&#39;s computer  200  is connected from the VGA output port to image acquisition module  220  using a standard VGA interface cable for interface cable  224 . Image data coming over the VGA cable from the presenter&#39;s computer  200  is digitized by the frame grabber module  370  and transferred to the main memory of controller module  380  via driver interface module  382 . Image compression module  384  periodically retrieves the digitized images from the main memory for compression purposes. In one contemplated embodiment, successive images are compared to see if the image has changed. In this embodiment, only changed images are transmitted to collaboration server  240 , thereby saving bandwidth. If an image is available that requires compression, image compression module  384  compresses the image for transmission to the collaboration server  240 . Although standard compression algorithms are contemplated, custom algorithms may be implemented by image compression module  384  or elsewhere in controller module  380  should it become advantageous to do so. Via networking process module  386  having control of the TCP/IP stack, and possibly using other HTTP routines, the compressed image is transferred to the collaboration server  240  via network interface module  390  over network  230 .  
         [0033]     In one possible embodiment, the operating system of controller module  380  is configured to use Dynamic Host Configuration Protocol (DHCP) to automatically and seamless obtain the IP address in the presenter&#39;s local area network for use in network transactions between image acquisition module  220  and collaboration server  240 .  
         [0034]     Continuing with the example wherein network  230  comprises the Internet, collaboration server  240  would have an HTTP server process implemented. Compressed images would be transferred using HTTP protocol. Alternatively, submissions of large blocks of data could be effected using POST or PUT requests.  
         [0035]     Remote meeting participants, such as remote participants  250  and  260  connect to collaboration server  240  over the Internet. Collaboration server  240  contains scripts providing instructions for reformatting the transferred images into a format accessible by the remote meeting participants. In the Internet case, the format would be that of a web page accessible by one of the ubiquitous web browser software applications such as NETSCAPE NAVIGATOR™ or MICROSOFT EXPLORER™. The web page would have embedded within it links to the received and reformatted compressed images. The embedded images would be updated on an ongoing basis as new images became available. Use of browser applets or ongoing web page refresh are two approaches contemplated.  
         [0036]     A number of enhancements and additional functions are also contemplated.  
         [0037]     For example, although this particular embodiment describes network  230  as being the Internet, no limitation of the interconnecting network is presumed. Insofar as image acquisition module  220  can transfer the images to collaboration server  240 , and remote users can access collaboration server  240 , any connection network is suitable. In the case of network  230  comprising the Internet, network  230  may be a network of networks, comprising local and wide area networks.  
         [0038]     In an alternative contemplated embodiment, collaboration server  240  may support a number of simultaneous presentations. Each presentation would be associated with an image acquisition box and particular meeting code. The particular meeting code number would be used to associate a particular presenter and appropriate meeting participants. The particular meeting code could be used as a part of a password authentication process and also incorporated into the image stream.  
         [0039]     In yet a further contemplated embodiment, in order to further minimize network bandwidth requirements, the image acquisition module  320  could implement a stream oriented protocol in which if a successive image differs from the previous image, only the differences are transmitted.  
         [0040]     In a contemplated enhancement to the collaboration server  240  to remote participant interface, instead of participants performing periodical checking for a new image, a permanent TCP/IP connection with a daemon on collaboration server  240  could be established, allowing image updates as they become available.  
         [0041]     Referring to  FIG. 4 , there may be seen a flowchart depicting a process for providing a network based conference according to an embodiment of the invention.  
         [0042]     The process commences at step  400 . At step  402  a connection is established between the presenter&#39;s computer and the image acquisition module. The physical connection, as described previously, is via a video interface cable connected to a video output port on the presenter&#39;s computer. At step  404  a connection is established between the image acquisition module and a collaboration server. At step  406  transmission of successive compressed and formatted images is commenced between the image acquisition module and the collaboration server. At step  408  a remote participant establishes a connection to the collaboration server. At step  410  the collaboration server presents the formatted images to the remote participant&#39;s computer. The network conference concludes for the remote participant at step  412 , where the connection between the remote participant&#39;s computer and collaboration server is concluded. At step  414  the network conference concludes as the connection between the image acquisition module and the collaboration server is concluded. At step  416  the collaboration server performs post conference processing. The process ends at step  420 .  
         [0043]     Each of the steps of the process admits a variety of sub-steps as previously described in the operation of the system. For example, step  402  may comprise establishment or confirmation of a particular meeting code. Alternatively this step could also include coordination of image transmission speed, image compression type, and other network signalling parameters. Likewise, step  408  may comprise authentication and authorization of the remote meeting participant. The post conference processing of step  416  may include billing, and archival functions. Although the steps have been portrayed as being executed in a particular sequence, this is not to be construed as the only or preferred sequence. For example, additional meeting participants may join in or depart the network conference at arbitrary points, necessitating repetition of steps  408  and  412  in parallel with step  410  i.e. while images are presented to other participants.  
         [0044]     While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations as fall within the spirit and broad scope of the appended claims.