Abstract:
An automatic camera steering control for directing video conferences including a communicator with a microphone and a voice activated LED emitter. Cameras receive an LED signal transmitted by the LED emitter and focus on the speaker associated with the activated LED emitter. A controller automatically selects and inserts into the video stream the audio and video of the speaker.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     This invention relates to systems and methods for manipulating a recording device. More particularly, this invention relates to automatically steering cameras to capture conference participants based on infrared signals received from a communication device worn by each participant. 
     2. Description of Related Art 
     Conventional video conference systems utilize a single camera with a single fixed focus to capture a meeting or presentation. These systems are advantageous in that the costs for the camera and other related equipment are low. However, utilizing only a single camera in this manner provides a rather static presentation, which is typically perceived as boring. For example, the captured presentation does not follow the flow of speaker or presentation activity within the meeting. 
     Vendors of conference systems have attempted to address these problems by adding multiple cameras to their systems. Multiple camera systems are advantageous in that they provide multiple views of the meeting. However, these systems are disadvantageous in that they require that a great deal of attention be focused on operating the system. For example, multiple video camera conferencing systems require that a dedicated operator perform various tasks, such as selecting a video feed from the multiple cameras, selecting a camera to zoom, deciding when to switch cameras to focus on another activity in the meeting, and deciding exactly which activity to switch to. 
     Therefore, conventional multi-camera systems require a trained operator to perform these functions, which imposes additional resource constraints on scheduling and conducting captured meetings and presentations. For example, when the operator is unavailable for some reason, such as due to a scheduling conflict, illness, etc., the meeting must be rescheduled. Similarly, if there is a desire to maintain secrecy of the subject matter of the meeting or presentation, the meeting must be scheduled around the availability of an operator with the appropriate clearance, if one even exists. 
     Due to current technological constraints, video conferencing may be encumbered by poor information bandwidth. Thus, various images, such as images of people, may have little resolvable detail, and current camera steering mechanisms, either automated or under human control, may also be subject to various problems, such as being activated by and thereby pointing at undesirable sounds (coffee pot, pencil tapping, etc.). These steering mechanisms may also be burdensome, and therefore operated improperly, if manual operation is required. 
     Experimental conference systems have been described in: “AutoAuditorium: a Fully Automatic, Multi-Camera System to Televise Auditorium Presentation,” by Bianchi, M., Joint DARPA/NIST Smart Spaces Technology Workshop, Gaithersburg, Md., Jul., 1998; and “Passive Capture and Structuring of Lectures,” by Mukhopadhyay, S. et al. in Proc. ACM Multimedia 99, pp. 477-487, 1999. However, these systems only operate under the limited conditions of a single speaker making a presentation. 
     U.S. Pat. No. 5,793,630, which is incorporated herein by reference in its entirety, discloses identifying spatially localizable portable electronic devices using video cameras capable of detecting both visible light and infrared. However, this system is limited to transferring electronic data to electronic devices at predetermined locations. 
     SUMMARY OF THE INVENTION 
     This invention provides systems and methods to automatically capture the presentations of participants at a meeting by utilizing a camera that steers and focuses on a participant based on a signal received by a communication device worn by each participant. 
     This invention separately provides systems and methods which utilize a camera that is steerable based on signals received from an infrared LED. 
     This invention separately provides systems and methods for utilizing communicators which include at least one infrared LED. 
     This invention separately provides systems and methods for encoding information in the infrared and/or audio streams. 
     This invention separately provides systems and methods for using a laser pointer with coaxial, modulated infrared beam to guide cameras. 
     In various exemplary embodiments of systems and methods according to this invention, an electronic CCD or CMOS video camera capable of detecting both visible light and infrared are provided. 
     In various exemplary embodiments according to the invention, a communicator, which includes a lightweight wireless microphone and at least one infrared LED, is used to identify a speaker and the speaker&#39;s location. In various exemplary embodiments, the LED is turned on when the microphone detects a sound level above a threshold. The light emitted by the LED is sensed by the camera and is used to point the camera to focus on the current speaker. 
     Various other exemplary embodiments of the systems and methods according to the invention include associating data with the microphone that is utilized by the video system to relate the data to the display video image. 
     In other exemplary embodiments of the invention, any suitable visible or non-visible wavelength of light may be used to send a signal to the camera. In other exemplary embodiments according to the systems and methods of the invention sounds that are undetectable to the human ear may be emitted by the communicator to steer the camera. However, the signal used may be any known or later-developed signal which can be transmitted and detected. 
     In other exemplary embodiments according to the systems and methods of the invention the camera may be replaced with any known or later-developed detection device. For example, the user may not require a video record, but may want to be alerted that someone is speaking. A photodetector may be used to pick up the LED signal and then may alert a user that the LED is activated. 
     In other exemplary embodiments according to the systems and methods of the invention the LED may be activated by something other than sound. Basically any known or later-developed system that detects something may activate the LED. For example, a user may want to capture an event such as an experiment being conducted in a laboratory. The user may be waiting for a particular event to occur such as for example the production of a certain chemical. A device that detects the chemical may be used to trigger the LED and thus start a video recording of the event. 
     In various exemplary embodiments of systems and methods according to this invention, a method of manipulating an image capturing device is provided that includes detecting a sensed condition; outputting an optical output signal based on the sensed condition; receiving the optical output signal; and manipulating the image capturing device based on the received optical output signal. 
     In various exemplary embodiments of systems and methods according to this invention, the detecting step includes detecting an audio signal. 
     In various exemplary embodiments of systems and methods according to this invention, the detecting step includes detecting an audio signal with a microphone disposed proximate a user. 
     In various exemplary embodiments of systems and methods according to this invention, the outputting step includes emitting a light signal with a light emitting diode (LED). 
     In various exemplary embodiments of systems and methods according to this invention, the outputting step includes emitting a light signal with an LED that is disposed proximate to a user. 
     In various exemplary embodiments of systems and methods according to this invention, the receiving step includes receiving the output light signal emitted by the LED. 
     In various exemplary embodiments of systems and methods according to this invention, the manipulating step includes manipulating an image capturing device based on the received light signal emitted by the LED. 
     In various exemplary embodiments of systems and methods according to this invention, the manipulating step includes orienting, zooming, focusing, or other control processes of the image capturing device so as to capture images of a user or users proximate a microphone that has detected an audio signal. 
     In various exemplary embodiments of systems and methods according to this invention, the manipulating step includes orienting the image capturing device so as to capture images of a user proximate an LED that has omitted a light signal. 
     In various exemplary embodiments of systems and methods according to this invention, the manipulating step includes controlling the image capturing device so as to capture images of multiple users proximate multiple microphones that have detected audio signals, either currently or at an earlier time. 
     In various exemplary embodiments of systems and methods according to this invention, a method for automatically operating an image capturing apparatus is provided that includes transmitting a light signal to the image capturing apparatus; and controlling the image capturing apparatus based on the transmitted light signal. 
     In various exemplary embodiments of systems and methods according to this invention, the transmitting step includes transmitting the light signal in response to an audio signal. 
     In various exemplary embodiments of systems and methods according to this invention, the transmitting step includes transmitting a light signal that is infrared. 
     In various exemplary embodiments of systems and methods according to this invention, an apparatus for manipulating an image capturing device is provided that includes a detector that detects a sensed condition; an optical output device that outputs an optical output signal based on the sensed condition; a receiving device that receives the optical output signal; and a controller that manipulates the image capturing device based on the received optical output signal. 
     In various exemplary embodiments of systems and methods according to this invention, the detector is an audio detector that detects an audio signal. 
     In various exemplary embodiments of systems and methods according to this invention, the detector is a microphone disposed proximate a user. 
     In various exemplary embodiments of systems and methods according to this invention, the optical output device emits a light signal using a light emitting diode (LED). 
     In various exemplary embodiments of systems and methods according to this invention, the receiving device receives the light signal emitted by the LED. 
     In various exemplary embodiments of systems and methods according to this invention, the receiving device is a video camera. 
     In various exemplary embodiments of systems and methods according to this invention, the controller manipulates an image capturing device based on the received light signal emitted by the LED. 
     An automatic image capturing apparatus control system comprising a communicator including a detector and transmitter, and an image capturing apparatus being controlled by signals emitted from the transmitter. 
     An image capturing apparatus control system wherein the transmitter emits a light signal in response to an audio signal detected by the detector. 
     However, the invention is not limited to the above described use of LEDs and other structures. For example, the invention is intended to cover any method and apparatus that manipulates a camera based on an optical signal. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows one exemplary embodiment of a communicator according to this invention. 
         FIG. 2  is a block diagram showing one exemplary embodiment of a system for automatic meeting capture according to this invention. 
         FIG. 3  is a block diagram of a image capturing device system according to one exemplary embodiment of the invention. 
         FIG. 4  is a block diagram of a media device according to one exemplary embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       FIG. 1  illustrates a communicator  10  with a microphone  11  and LED  12 . The microphone  11  can be wireless, or can be any suitable device for picking up and transmitting audio signals. The communicator  10  can be worn by participants on their clothes, eyeglasses, etc. In one exemplary embodiment according to the systems and methods of the invention, the one or more LED  12  emits modulated IR LED emissions. (IR emissions are desirable because they are not humanly observable, however the camera is sensitive to IR wavelengths. However, in various exemplary embodiments visible wavelengths can also be used.) The modulated IR LED emissions may contain encoded information, but can primarily be used for automatic camera steering control. Each potential participant in a video conference can have a communicator  10 . Audio signals above a certain threshold can be used to activate transmission of IR signals. 
     In various exemplary embodiments of the systems and methods according to the invention an optional omnidirectional LED signal photosensor, or array of photosensors which can determine the angle of incidence of LED signals, can be used to sense all LED signals. The sensed modulated signals can be compared with those detected via the cameras. Any detected signals which are not present from the cameras can be used to cause one or more cameras to zoom out and orient towards the new LED sources. 
     In various exemplary embodiments of the invention, communicators  10  can be programmed at the beginning of the session to result in the view triggered by the communicator  10  to be a fixed offset from center of the communicator  10 . For example, if the participant is wearing the communicator  10 , such as on his or her left shirt pocket, the system can find the head of the participant relative to the communicator  10  by computing an offset/perspective correction based on the IR emission (for example, based on a training procedure in which a user has offset the camera from the associated LED to point at the user&#39;s face or a group of proximal faces), or by using a head finding algorithm that finds the head nearest to the communicator, rather than just using the centroid. 
     In various exemplary embodiments of the systems and methods according to the invention the communicator  10  may have a button to toggle the view, mute the microphone  11 , and change the display to, for example, a split screen. 
     In various exemplary embodiments of the systems and methods according to the invention the communicator  10  may have an input device which allows the user to input the user&#39;s name and/or other information, such as a pointer into a database, for the system to associate with the communicator. 
     In one exemplary embodiment according to the systems and methods of the invention, infrared LEDs  12  can intermittently emit infrared detection signals to establish spatial location. The pattern of infrared blinking seen through comparison of multiple frames of the video cameras  20  can be used to positively identify infrared LEDs  12  and transfer identification information or other data. Use of two or more LEDs  12  could allow, through triangulation, determination of the angle of rotation of an object to assist in steering for cameras  20 . Use of multiple LEDs  12  can increase accuracy of position determination and multiple identification LEDs can be used to increase the rate of data transfer. Two or more LEDs  12  can also be used to determine distance from the cameras  20 . Therefore focusing and/or zooming can be controlled based simply on geometry. 
     A variety of infrared signal sources can be used for camera calibration, spatial localization identification and data transfer. In one exemplary embodiment of the invention infrared signal sources can be active infrared tags that internally generate infrared light or passive infrared tags that controllably reflect incident infrared light in response to incident infrared light provided by an infrared light source. A lithium battery, photoelectric cell or other known or later-developed long life power source can apply a low voltage power source for driving the modules. In the default state modules can be held in a power down mode. It should be appreciated that any known or later-developed light source suitable for camera steering may be employed according to the systems and methods of the invention. 
     In various exemplary embodiments of the invention, information associated with each participant can be input to the communicator by various means such as alphanumeric keying. Data may be downloaded to the camera control unit  30  at the start of the session, or whenever the LED  12  is active and in the field of the camera  20 . Alternatively, the information can be embedded in the audio stream. Alternatively, information is loaded into the system at the central unit. In various exemplary embodiments, the LED  12  on the communicator  10  can output a fixed ID which then can be looked up in a central database contained in memory  37  or accessible over a network. In various exemplary embodiments a user could pull up a web page containing information to program the communicator  10  with data. In other exemplary embodiments a user could have a personal communicator  10 , preprogrammed with user information. 
     The participant information may be displayed on the video recording. For example, the name of the participant may be displayed as well as any other pertinent information. Pre-recorded exhibits may be matched with the participant based on the participant information, and automatically included in the display or called up by use of a switch on the communicator  10 . 
     In one exemplary embodiment, cameras  20  can be conventional and widely commercially available CCD or CMOS video cameras having overlapping fields of view. The video cameras  20  can be capable of detecting both visible light and infrared, and are further configured to capture a sequence of images at predefined frame rates. Electronics associated with the cameras  20  can separate video and LED information and send signals to the camera control unit  30 . It should be appreciated that any known or later-developed cameras capable of detecting a transmitted signal may be employed according to the systems and methods of the invention. 
     Audio information may be used to determine which audio and video signal is output by the camera control unit  30  to the media cabinet  40  for display, transmission and/or recording. The media cabinet  40  can record the information on any suitable known or later developed recording medium such as VHS or digital recording. If the camera control unit  30  determines that there are simultaneous speakers, then more than one video and audio signal can be output to the media cabinet  40  which may combine the information in any suitable manner. For example, the information can be recorded in a split screen format, or the camera can pan, zoom and focus to include the multiple speakers or even the present and previous speakers. 
     A communicator  10  that picks up an audio signal above a set threshold includes a circuit that can activate the LEDs  12  to emit an infrared signal. The infrared signal can be detected by one or more video cameras  20 . Video cameras  20  can send an image signal and a spatialization signal to camera control unit  30 . The camera control unit  30  can receive the signals from one or more cameras  20 . In one exemplary embodiment according to the systems and methods of the invention, a single camera  20  may be employed. Once the camera  20  receives the IR signal emitted from a communicator  10 , the camera  20  may maintain focus on the participant associated with that communicator  10  until the communicator  10  no longer emits a signal. Alternatively, the system may be programmed to focus on a participant who speaks the loudest, by controlling the LED  12  emission based on the speaker&#39;s volume. 
     In another exemplary embodiment according to the systems and methods of the invention, one of the participants such as a moderator may be given the ability to prioritize participants. Prior to the start of the conference each participant&#39;s communicator  10  could be encoded with a priority code relative to each participant. The code would give a participant priority over some or all other participants. The priority of a participant may change over the course of a conference. For example, in a debate the participant who is exercising his/her opportunity to respond would be given priority. Many of the above described exemplary embodiments would work as well with the use of multiple camera  10  systems. 
     By comparing the infrared signal in accordance with the audio signal the camera control unit  20  is able to match the appropriate signals. If one communicator  10  is in use, the camera  20  control unit  30  can make a determination as to which camera  20  is able to obtain the best resolution for capturing the speaker. The camera control unit  30  can adjust the cameras  20  to obtain the best angle for each and then determine which camera  20  can produce the best picture based on predetermined parameters such as best angle of vision. The camera control unit  30  can then forward the image signal to media device  40 . 
     The media device  40  includes an input/output  42 , display  44  and/or a recorder  46 . The input/output may include the standard inputs commonly found on any recording device. This includes play, pause, fast forward, rewind and stop. The input/output may also allow the user to perform editing functions. For example, if more than one participant speaks at a time, the user may want to have the video recording switch to a split screen. After reviewing the recording the user may decide that it is preferable to maintain a single screen. The user may be able to edit the recording to revert to a single screen display. 
     The recorder may be an analog, digital or any other known or later developed recording means. The recorder may include the capability to provide multiple recordings so that each participant can receive a copy. 
     The camera control unit  30  includes an audio signal analyzing circuit  32 , a camera select circuit  34 , a video signal analyzing circuit  36  a memory  37 , a camera control circuit  38 , and an optional omnidirectional LED sensing circuit, (not shown). The audio signal analyzing circuit  32  receives an audio signal transmitted by microphone  11 . The communicator  10  has previously been associated with a participant as described above. The signal may be transmitted by any known or later developed suitable means including R/F transmission or wires. The signal can be analyzed to prevent the recording of incidental noises. If the video signal analyzing circuit  36  determines that the signal warrants recording, for example, based on the previously described priority, the audio signal and video signal will be transmitted to the media device  40 . 
     Camera control unit  30  can detect the modulated LED signals interpret the LED information to control the camera The camera select circuit  34  can determine which camera  20  or cameras will be used to collect the video signal. The camera select circuit can send a signal to the camera control circuit  34  which can adjust the cameras  20  selected by the camera select circuit  34 . The camera control circuit  34  can send a signal to camera controller  22 . Camera controller  22  may include any suitable known or later-developed system for performing an inclination, declination, panning, zoom and focusing function for the camera, as well as any other now or later developed camera control functions. 
     Optional omnidirectional sensing circuit is used to detect active LEDs which are not in the current field of view of any camera. A modulated signal which does not correlate with one of the LED signals being detected by a camera is used by the camera control unit  30  to zoom out and pan one or more cameras to accept the new LED signal location. If the LED position had been previously entered, the camera control unit  30  need only pan an appropriate camera to the associated speaker. 
     The functions of the camera control unit  30  may be implemented on a programmed general purpose computer. However, the camera control unit  30  functions can also be implemented on a special purpose computer, a programmed microprocessor or microcontroller and peripheral integrated circuit elements, an ASIC or other integrated circuit, a digital signal processor, a hardwired electronic or logic circuit such as a discrete element circuit, a programmable logic device such as a PLD, PLA, FPGA or PAL, or the like. 
     The memory  37  can be implemented using an appropriate combination of alterable, volatile or non-volatile memory of non-alterable, or fixed, memory. The alterable memory, whether volatile or non-volatile, can be implemented using any one or more of static or dynamic RAM, a floppy disk and disk drive, a writable or re-writable optical disk and disk drive, a hard drive, flash memory or the like. Similarly, the non-alterable or fixed memory can be implemented using any one or more of ROM, PROM, EPROM, EEPROM, an optical ROM disk, such as a CD-ROM or DVD-ROM disk, and disk drive or the like. 
     When the LEDs  12  of the communicator  10  are activated by the participant speaking, the operation of the LEDs  12  can be picked up by one or more of the cameras  20 . The LEDs transmit a signal that is associated with communicator  10  from which it emanates. The cameras  20  transmit a video signal to the video signal analyzing circuit  36 . The video signal may be transmitted by any suitable known or later-developed means including cable or wireless transmission. The signal or signals can be analyzed by the camera select circuit  34 . Cameras  20  in a predetermined referenced position to visually record the participant associated with an activated communicator  10  may begin to have their output collected. The camera select circuit  34  may choose a default camera, a camera determined to initially be in the best position to record or may store in memory  37  all camera signals until a final camera is chosen. The final camera may be chosen based on its final position after each of the cameras are adjusted by the camera steering circuit  38  to optimize the view of participant or participants associated with an activated communicator  10 . The audio signal and the video signal will be appropriately matched by the video signal analyzing circuit  36  and directed to the media device  40  where it will be combined into the same video stream. 
     In a similar manner a camera control unit  30  can select speakers and cameras at separate locations, such as different cities. In a similar manner, a recorder may be associated with each camera, with the “selection” of data from an individual camera happening based on the recorded IR signals long after the recording has been completed. This enables creation of multiple viewpoints of a large event. 
     In various exemplary embodiments the time delay that may occur between the point in time a speaker begins to speak and the point in time the speaker&#39;s image begins to be captured may be minimized or set so that brief utterances are filtered. 
     The LEDs  12  associated with inactive communicators  10  may intermittently emit an infrared signal. The signal will be detected by the video cameras  20  not currently being used to record a speaker. The video cameras  20  can then be positioned so that when a participant begins speaking, the camera will need minimal adjustment when it begins to record the speaker. 
     In one exemplary embodiment according to the systems and methods of the invention one or more conference participants are given a pointer capable of emitting a modulated beam or beams in a wavelength range which the camera can sense. A speaker may want to incorporate an exhibit into his presentation. By aiming the pointer at a display screen, for example, a camera  20  can focus on the view screen and the view screen may temporarily replace the speaker on a display of the conference. In other exemplary embodiments the conference display may present a pre-defined viewing format such as split-screen that shows both the speaker and the view screen. 
     In other exemplary embodiments according to the systems and methods of the invention, the speaker may use the pointer to draw an outline around an exhibit, such as a sheet of paper. The speaker may then place the exhibit so as to be in view of a camera  20  other than the camera  20  which is capturing the image of the speaker. Further, the participant can choose to have the drawn path used as an overlay on the current video images. In various exemplary embodiments a camera  20  may be dedicated to capturing exhibits. In various other exemplary embodiments the participant may hold up the exhibit so that the camera  20  capturing the image of the speaker also captures the exhibit. The system will perform an offset/correction based on the LED signal of the communicator  10  and the signal of the pointer. Similarly, the selection of communicators may be determined based on the presentation material being displayed by the speaker. For instance, when bullet  3  of slide # 34  is displayed, pan to communicator # 32  to gauge the listener&#39;s reaction. 
     While this invention has been described in conjunction with the exemplary embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the exemplary embodiments of the invention, as set forth above, are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention.