Patent Publication Number: US-2005140777-A1

Title: Dataconferencing system and method

Description:
TECHNICAL FIELD OF THE INVENTION  
      The present invention relates generally to the field of data communications and, more particularly, to a dataconferencing system and method.  
     BACKGROUND OF THE INVENTION  
      Remote sites may be connected using the Internet, an intranet, or over standard telephone lines to accommodate conferencing between the sites. For example, each site may include a microphone, speakerphone, or other device for transmitting audio signals between the sites, a camera for generating and transmitting video signals between the sites, and perhaps a whiteboard for sharing written data between the sites. Each site may also include an overhead projector for remotely viewing documents.  
      Present dataconferencing systems, however, suffer several disadvantages. For example, in the case of document viewing, inadequate lighting may cause shadowing on portions of the document, thereby resulting in poor image quality and difficulty in viewing the document by the remote site. Additional lighting may be used to increase the light intensity directed toward the document. However, the additional lighting often generates excessive amounts of heat, consumes additional power, and creates glare. Further, present dataconferencing systems may also be limited to providing intermittent snapshots of transparency slides. Thus, present systems may be incapable of providing real-time remote image viewing which may be desirable for classroom teaching or other applications.  
     SUMMARY OF THE INVENTION  
      In accordance with one embodiment of the present invention, a dataconferencing system comprises an imaging device adapted to generate an image of a document. The system also comprises a light source adapted to generate light proximate to the document for generating the image. A monitor application accessible by a processor is adapted to detect a change corresponding to the document. A lighting application accessible by the processor is adapted to automatically activate the light source in response to the detected change.  
      In accordance with another embodiment of the present invention, a dataconferencing method comprises receiving a document. The method also comprises detecting a change to the document and automatically activating a light source to generate light proximate to the document in response to the detected change. The method further comprises generating an image of the document using the generated light. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following descriptions taken in connection with the accompanying drawings in which:  
       FIG. 1  is a perspective diagram illustrating an embodiment of a dataconferencing system in accordance with the present invention;  
       FIG. 2  is a block diagram illustrating an embodiment of a dataconferencing system in accordance with the present invention; and  
       FIGS. 3A and 3B  are a flow chart illustrating a method for dataconferencing in accordance with an embodiment of the present invention.  
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS  
      The preferred embodiments of the present invention and the advantages thereof are best understood by referring to  FIGS. 1-3  of the drawings, like numerals being used for like and corresponding parts of the various drawings.  
       FIG. 1  is a perspective diagram illustrating an embodiment of a dataconferencing system  10  in accordance with the present invention. Briefly, system  10  provides high resolution images of documents for dataconferencing with remote sites. For example, in one embodiment, a combination of a strobe light source and a constant light source are used to accommodate various lighting requirements for producing a high resolution image of a document. The strobe light source is automatically and intermittently triggered in response to changes to the document or changes in the vicinity of the document to provide a desired intensity of light directed toward the document for high resolution image generation corresponding to the document. As the frequency of changes to the document or in the vicinity of the document increases, the constant light source may be activated to provide a generally constant light directed toward the document for continued image gathering corresponding to the document.  
      Referring to  FIG. 1 , system  10  comprises a display  12  for providing a mounting or display surface for a document  14  to be dataconferenced with a remote site. Document  14  may comprise an opaque, translucent, or transparent document. System  10  also comprises an imaging device  16  for generating an image of document  14 . Imaging device  16  may comprise an analog or digital camera or other device for generating an image of document  14  now known or later developed.  
      In the illustrated embodiment, system  10  also comprises one or more strobe light sources  18  and one or more constant light sources  20 . Strobe light source(s)  18  are adapted to provide intermittent lighting directed toward document  14  when generating an image of document  14  using imaging device  16 . Constant light source(s)  20  are used to provide a generally constant source of light directed toward document  14  when generating an image using imaging device  16 . Thus, while strobe light source(s)  18  provide intermittent bursts of light energy upon activation, constant light source(s)  20  are generally always on or activated, thereby generating a substantially constant source of light energy. Additionally, as will be described in greater detail below, constant light source(s)  20  may also be configured to provide varying intensities of constant light. In the illustrated embodiment, light sources  18 ,  20  are disposed at approximately a sixty degree angle relative to document  14  such that light generated by light sources  18 ,  20  reflect from document  14  to imaging device  16 . However, other angular orientations and/or positions of light sources  18 ,  20  may be used relative to document  14  and imaging device  16 .  
      In operation, imaging device  16  generates a series of images of document  14  to determine whether changes to document  14  require generation of a high resolution image of document  14  for transmittal to a remote site. As used herein, a low resolution image may comprise an image having limited clarity, definition, or other characteristics, and a high resolution image comprises an image having greater clarity, definition, or other characteristics than a low resolution image. Thus, high resolution images may be desired for transmittal to a remote site for viewing while low resolution images may be sufficient to detect changes to document  14  or for other purposes. The series of images for change detection may be generated using ambient light or light generated by constant light source(s)  20 . For example, if ambient light is insufficient to generate an image of document  14  of sufficient resolution to detect changes to document  14 , constant light source(s)  20  may be activated at a generally low intensity level to provide the desired level of resolution. The series of images generated of document  14  are evaluated to detect changes corresponding to document  14 . If a change occurs to document  14 , strobe light source(s)  18  may be activated to produce a generally short and high intensity light burst directed toward document  14  for generating a high resolution image of document  14  using imaging device  16 . The high resolution image of document  14  may then be transmitted to a remote site. If a frequency of changes to document  14  increases, constant light source(s)  20  may be activated, or the intensity increased, to provide a generally constant source of light directed toward document  14  such that imaging device  16  generates a series of high resolution images for transmittal to the remote site. After the frequency of changes to document  14  decreases, constant light source(s)  20  may be deactivated or the intensity level decreased.  
      System  10  may also comprise a motion detector  22  for detecting motion proximate to document  14 . In operation, in response to motion detected proximate to document  14 , strobe light sources  18  may be activated to direct light toward document  14  for generating a high resolution image of document  14  using imaging device  16 . As described above, as a frequency of motion proximate to document  14  increases, constant light sources  20  may also be activated to generate a generally constant source of light directed toward document  14  for generating a series of high resolution images of document  14 . After generation, the high resolution image(s) may then be transmitted to the remote site.  
      As described above, system  10  may be adapted to operate substantially automatically for creation of high resolution images of document  14  in response to changes to document  14  or motion proximate to document  14 . System  10  may also be configured to accommodate manual intervention by a user of system  10 . For example, imaging device  16  may comprise one or more keypads  24  for activation by the user. In operation, in response to activation of one of keypads  24 , strobe light source  18  may be activated to generate a flash of light directed toward document  14  for generating a high resolution image of document  14  using imaging device  16 . As described above, the high resolution image may then be transmitted to a remote site. Keypads  24  may also be used to activate constant light source  20  in anticipation of continued changes to document  14  such that a generally constant source of light is directed toward document  14  for generation of a substantially continuous series of high resolution images to be transmitted to the remote site.  
       FIG. 2  is a block diagram illustrating an embodiment of system  10  in accordance with the present invention. System  10  generates images corresponding to document  14  to accommodate dataconferencing with a remote site  26 . The images may be transmitted via a communication network  28 , such as the Internet, an intranet, or other wired or wireless communication mediums now known or later developed. System  10  preferably comprises input devices  30 , output devices  32 , a processor  34 , and a memory  36 . In this embodiment, input devices  30  comprise imaging device  16 , motion detector  22 , and keypad  24 . Input devices  30  may also include other devices such as a keyboard, pointing device, such as a mouse or a track pad, a scanner, or other type of device for inputting information into system  10  now known or later developed. In the illustrated embodiment, output devices  32  comprise strobe light source(s)  18  and constant light source(s)  20 . However, output devices  32  may also comprise a monitor, display, printer, communication network  28  port, or other type of device or outlet for generating an output now known or later developed. Components of system  10  may be located in relatively close proximity to each other or located remote from each other. For example, processor  34  and/or memory  36  may be located remote from imaging device  12  or other components of system  10 , such as in another room, building, or city, and coupled to device  12  and other components of system  10  using wired or wireless communication networks.  
      The present invention also encompasses computer software that may be executed by processor  34 . In the illustrated embodiment, memory  36  comprises a monitor, application  40  and a lighting application  42 , which in this embodiment are computer software programs. However, it should be understood that system  10  may be configured having software, hardware, and/or a combination of software and hardware components. In  FIG. 2 , monitor application  40  and lighting application  42  are illustrated as stored in memory  36 , where they may be executed by processor  34 . However, applications  40 ,  42  may be otherwise stored such that applications  40 ,  42  are accessible by processor  34 . Briefly, monitor application  40  monitors changes to document  14  or changes proximate to document  14 . In response to a detected change by monitor application  40 , lighting application  42  controls activation of strobe light source(s)  18  and/or constant light source(s)  20  for generation of high resolution images of document  14 .  
      In the illustrated embodiment, system  10  also comprises a database  40  stored in memory  36 . Database  40  comprises information associated with images generated by imaging device  16 . For example, in the illustrated embodiment, database  44  comprises image data  50  and variation criteria  52 . Briefly, image data  50  comprises information associated with the images generated by imaging device  16 , which may comprise low resolution images used to determine changes corresponding to document  14  or high resolution images for transmittal to a remote site. Variation criteria  52  comprise one or more criterion or information associated with detecting changes to document  14  or changes proximate to document  14 .  
      As described above, image data  50  comprise information associated with images generated by imaging device  16 . In the illustrated embodiment, image data  50  comprise detection images  60  and transmittal images  62 . Detection images  60  comprise low resolution image information generated by imaging device  16  for determining whether a change to document  14  requires generation of a high resolution image. Detection images  60  may be generated by imaging device  16  using ambient light or using light generated by constant light source  20 . For example, as described above, constant light source  20  may be adapted to generate a desired intensity of light to produce an image of sufficient resolution to enable detection of changes to document  14  while generating a minimum amount of thermal energy and consuming minimal power. Detection images  60  represent low resolution images of document  14  that may be compared to variation criteria  52  to determine whether a change to document  14  has occurred which may require generation of a high resolution image of document  14  for transmittal to remote site  26 . Transmittal images  62  comprise the high resolution image information corresponding to document  14  for transmittal to remote site  26 .  
      Variation criteria  52  comprise information associated with evaluating detection images  60  to determine whether a sufficient change to document  14  has occurred, thereby requiring generation of a transmittal image  62 . A variety of methods may be used to evaluate detection images  60  to determine whether changes between compared detection images  60  require generation of a transmittal image  62 . In the illustrated embodiment, variation criteria  52  comprises pixel characteristics  64  and contrast characteristics  66 . Pixel characteristics  64  comprise comparison information of detection images  60  based on the pixels contained within the detection image  60 . For example, pixel characteristics  64  may be based on a color designation assigned to each pixel of detection images  60  such that if variations in quantity or color designations associated with the pixels of detection images  60  exceed a predetermined level, generation of a transmittal image  62  is required. Contrast characteristics  66  comprises information associated with contrast differences between compared detection images  60  to determine whether a transmittal image  62  is required. For example, detection images  60  may be compared to determine whether a contrast value corresponding to various portions of each detection image  60  exceeds a predetermined level, thereby requiring generation of a transmittal image  62 .  
      In operation, monitor application  40  evaluates detection images  60  to determine whether variations between two detection images  60  exceeds a predetermined level, thereby requiring generation of a transmittal image  62 . For example, imaging device  16  may be adapted to generate detection images  60  at a predetermined interval and store detection images  60  in database  44 . Monitor application  40  may compare detection images  60  using variation criteria  52  to determine whether variations to detection images  60  indicate a sufficient change to document  14 , thereby requiring generation of a transmittal image  62 . Monitor application  40  may be adapted to compare successive detection images  60  or compare non-successive detection images  60  using variation criteria  52 . For example, monitor application  40  may be adapted to use a single detection image  60  as a baseline for comparing a series of successive detection images until differences between one of the successive detection images  60  and the baseline detection image  60  exceed the predetermined variation criteria  52 . Alternatively, monitor application  40  may be adapted to compare pairs of successive detection images  60  until differences between the pair of successive detection images  60  exceed the predetermined variation criteria  52 .  
      After variations between compared detection images  60  exceed a predetermined level associated with variation criteria  52 , lighting application  42  activates strobe light source  18  to direct light toward document  14  for generation of a high resolution image of document  14 . Additionally, lighting application  42  synchronizes activation of imaging device  16  corresponding to activation of strobe light source  18  for generating the high resolution image of document  14 . As described above, variation criteria  52  may also comprise frequency data  68  having information associated with the frequency of generated high resolution images of document  14 . Thus, for example, monitor application  40  also determines whether a frequency of generated high resolution images exceeds a predetermined level corresponding to frequency data  68 . If the frequency of high resolution images exceeds the predetermined frequency data  68 , lighting application  42  activates constant light source  20  to provide a generally constant light directed toward document  14  such that imaging device  16  may generate a series of high resolution images corresponding to document  14 . Alternatively, as described above, if ambient light is insufficient to generate detection images  60  of sufficient resolution and a relatively low intensity of light is generated by constant light source(s)  20  for generating detection images  60 , lighting application  42  may increase the intensity level of the light generated by constant light source(s)  20  in response to exceeding a predetermined frequency of high resolution images.  
      Lighting application  42  also monitors and controls the intensity of light generated by constant light source(s)  20  such that as constant light source(s)  20  reaches a desired intensity, lighting application  42  may cease or terminate additional activation of strobe light source(s)  18 . Thus, if constant light source(s)  20  are used to generate low resolution detection images  60 , system  10  may be adapted to continue strobe light source  18  activation for generation of high resolution transmittal images  62  of document  14  until constant light source(s)  20  reach a desired intensity, at which time constant light source(s)  20  may be used to generate high resolution transmittal images  62 . Correspondingly, as the frequency of generation of high resolution transmittal images  62  decreases to below the predetermined level associated with frequency data  68 , lighting application  42  may deactivate or decrease the intensity level of constant light source(s)  20  and initiate activation of strobe light source(s)  18  for a next high resolution transmittal image  62 . System  10  may also be configured such that when strobe light source(s)  18  are activated, constant light source(s)  20  are deactivated, and vice versa.  
      Additionally, system  10  may transmit data to remote site  26  using a variety of methods. For example, system  10  may be adapted to transmit images  62  to remote site  26  as images  62  are generated. Thus, if changes to document  14  are infrequent, a quantity of data transmitted to remote site  26  is minimized. Alternatively, system  10  may be adapted to repeatedly transmit the same image  62  to remote site  26  until another image  62  indicating a change to document  14  has been generated, at which time the new image  62  may be repeatedly transmitted to remote site  26 .  
       FIGS. 3A and 3B  are a flowchart illustrating a method for dataconferencing in accordance with an embodiment of the present invention. The method begins at step  100 , where system  10  receives a document  14  for use in dataconferencing. At step  102 , lighting application  42  activates strobe light source  18 . At step  104 , imaging device  16  generates a transmittal image  62  of document  14  during activation of strobe light source  18 . At step  106 , the generated transmittal image  62  is communicated to remote site  26  via communication network  28 .  
      At step  108 , imaging device  16  generates a detection image  60  corresponding to document  14 . As described above, detection images  60  may be generated using ambient light or lighting application  42  may activate constant light source  20  at a relatively low intensity for the generation of detection images  60 . At step  110 , monitor application  40  compares the transmittal image  62  generated at step  104  with the detection image  60  generated at step  108 . At decisional step  112 , monitor application  40  determines whether variations between the transmittal image  62  and the detection image  60  exceed variation criteria  52 . If the variations between the transmittal image  62  and the detection image  60  do not exceed variation criteria  52 , the method proceeds from step  112  to step  114 , where imaging device  16  generates another detection image  60 . At step  116 , monitor application  40  compares the generated detection images  60  using variation criteria  52 . At decisional step  118 , a determination is made whether variations between the compared detection images  60  exceed variation criteria  52 . If the variation between compared detection images  60  does not exceed a predetermined level associated with variation criteria  52 , the method returns to step  114 . If the variation between compared detection images  60  does exceed a predetermined level associated with variation criteria  52 , the method proceeds from step  118  to step  120 . Additionally, at decisional step  112 , if the variation between the transmittal image  62  generated at step  104  and the detection image  60  generated at step  108  does exceed a predetermined level associated with variation criteria  52 , the method proceeds from step  112  to step  120 .  
      At step  120 , monitor application  40  determines a frequency associated with generation of transmittal images  62 . If the frequency of transmittal image  62  generation does not exceed a predetermined level associated with frequency data  68 , the method returns to step  102 . If the frequency of transmittal image  62  generation exceeds a predetermined level associated with frequency data  68 , the method proceeds from step  122  to step  124 , where lighting application  42  activates strobe light source  18 . At step  126 , lighting application  42  also activates constant light source  20 . For example, the intensity level of constant light source  20  may be adjustable such that the intensity level may be increased until reaching a sufficient level to produce high resolution images, or constant light source  20  may require time to warm up before reaching a sufficient intensity level. At step  128 , imaging device  16  generates a transmittal image  62  associated with document  14 . At step  130 , the generated transmittal image  62  is transmitted to remote site  26  via communication network  28 .  
      At step  132 , monitor application  40  generates a detection image  60  using imaging device  16 . At step  134 , monitor application  40  compares the transmittal image  62  generated at step  130  with the detection image  60  generated at step  132 . At decisional step  136 , monitor application  40  determines whether a variation between the transmittal image  62  generated at step  130  and the detection image  60  generated at step  132  exceeds a predetermined level associated with variation criteria  52 . If the variation exceeds the predetermined level, the method proceeds from step  136  to step  138 , where monitor application  40  determines a frequency of transmittal image generation. If the frequency associated with transmittal image  62  generation exceeds a predetermined level associated with frequency data  68 , the method proceeds from step  140  to step  142 , where lighting application  42  determines an intensity of constant light source  20 . At decisional step  144 , lighting application  42  determines whether the intensity of constant light source  20  corresponds to a predetermined level for generating high resolution images of document  14 . If the intensity of constant light source  20  is at the required level, the method returns to step  128 . If the intensity of constant light source  20  is not at the desired level, the method proceeds from step  144  to step  146 , where lighting application  42  activates strobe light source  18  for generation of the high resolution image.  
      At decisional step  136 , if the variation between the transmittal image generated at step  130  and the detection image generated at step  132  does not exceed a predetermined level associated with variation criteria  52 , the method proceeds from step  136  to step  148 , where lighting application  42  deactivates constant light source  20 . Additionally, at decisional step  140 , if the frequency of transmittal image  62  generation does not exceed a predetermined level associated with frequency data  68 , the method proceeds from step  140  to step  148 . At decisional step  150 , a determination is made whether additional images of document  14  are required for dataconferencing. If additional images are required, the method returns to step  114 . If no additional images are required, the method ends.