Abstract: The present invention allows the resources of multiple multipoint control units (MCUS) in a multipoint multimedia communication system. A plurality of multimedia terminals support different multimedia conferencing protocols, and a multipoint control unit communicates with a multipoint processor unit and with the multimedia terminals for signaling and call control. At least one multipoint processor unit communicates with the plurality of multimedia terminals for media and optionally call signaling and call control. The multipoint processor unit also communicates with the multipoint control unit for interfacing the call signaling and the call control information between said multipoint control unit and the terminals.

Abstract: A system and method is disclosed for preparing video conference images. An endpoint has a wide screen display. The disclosed system creates an image with an aspect ratio of about 16:9 for the endpoint. The image is altered or modified to change the aspect ratio to about 4:3. In one example, two portions can be added to the image to increase the overall height of the image. The wide screen display is set to a zoom mode and is capable of substantially displaying the image without the added portions. Alternatively, the image is stretched along its height by a factor of 4/3. The wide screen display is set to the wide mode and is capable of substantially displaying the image without the stretched height. The disclosed system and method can receive signals that the endpoint has a wide screen display and can also inform a user at the endpoint to set the wide screen display to the wide or zoom modes.

Abstract: The present disclosure provides methods of establishing communication between endpoints located in different gatekeeper zones. An electronic message comprising (i) an alias for a first endpoint and (ii) an address of a first gatekeeper associated with the first endpoint is delivered from a first computer associated with the first endpoint to a second computer associated with a second endpoint. Alternatively, the deliverance of the message can occur within the same computer. Upon receiving the message, a second endpoint is instructed to replace its original gatekeeper address with the gatekeeper address listed in the message. Subsequently, the second endpoint uses the alias of the first endpoint to establish communication with the first endpoint.

Abstract: A videoconferencing apparatus includes a multi-point (MP) conference application that enables the apparatus to combine and distribute audio and video signals received from a plurality of remote conference endpoints, thereby obviating the need to provide a separate multi-point control unit having hardware-based inverse multiplexers (IMUXs). The MP conference application is configured to generate, for each remote conference endpoint participating in a conference, discrete instances of a signal processing train by means of dynamically allocable IMUXs, each processing train including a communication process and audio/video/data codecs. The processed audio and video signals are subsequently conveyed to an audio mixer and video switching module for combination with locally-generated audio and video signals.

Abstract: A method for dynamically allocating MCU resources during a multipoint network event such as a conference call. The method determines the number of MCU resources to allocate for the start of the multipoint network event and then at each of a plurality of modeling intervals during the multipoint event adjusts the number of allocated MCU resources based upon actual inbound users. Self-tuning of the allocation of MCU resources for multipoint events occurs in advance of use by providing a look ahead allocation of resources based on what is likely to be needed in the future for a conferencing event. The number of multipoint events occurring within a tuning interval are counted. The number of MCU resources actually utilized during each multipoint event are accumulated and then a probability value is determined for future use of MCU resources for an upcoming multipoint event.

Abstract: An audio conferencing apparatus and method. The apparatus includes a data bus, such as a TDM bus, a controller, and an interface circuit that receives audio signals from a plurality of conference participants and provides digitized audio signals in assigned time slots over the TDM bus. The audio conferencing platform also includes a plurality of digital signal processors (DSPs) adapted to communicate on the TDM bus with the interface circuit. At least one of the DSPs sums a plurality of the digitized audio signals associated with conference participants who are speaking, to provide a summed conference signal. This DSP provides the summed conference signal to at least one of the other DSPs, which removes the digitized audio signal associated with a speaker whose voice is included in the summed conference signal, to provide a customized conference audio signal to each of the speakers.

Abstract: A system for handling data representative of audio/video information in a conferencing device. The system comprises a set of modules and subsystems for processing the data. The system further comprises at least one channel for transferring processed data between selected ones of the modules and subsystems, the at least one channel having a first buffer list associated therewith. Additionally, a work routine called by the at least one channel is configured to remove a buffer from the first buffer list and to send the buffer to an output routine called by the at least one channel.

Abstract: A positioning device is provided for rotatably positioning a camera or other article about orthogonal rotational axes. The positioning device includes a carriage supported for rotation about a horizontal axis by a yoke. The yoke is in turn rotatably coupled to a base assembly for rotation of the yoke about a vertical axis. Rotation of the camera about the horizontal and vertical axes is respectively effected by first and second voice coil actuators, each comprising a pair of magnets and at least one coil to which current is supplied. The amplitude and direction of the current supplied to the coil determines the speed and direction of rotation of the camera. The second voice coil actuator preferably includes a coil assembly comprising two opposed coils. This design overcomes the angular range limitations associated with prior art voice coil actuators and enables rotation of the camera about an extended angular range.

Abstract: An overhead microphone assembly using multiple unidirectional microphone elements. The microphone assembly is installed overhead, generally above all the desired sound sources and below the undesired sound sources. The signals from these multiple microphone elements are fed into a microphone steering processor which can mix and gate the signals to ensure the best signal/noise ratio. The steering processor may also track the sound source dynamically when such tracking (source locating) is desired. The resulting audio signal from the steering processor may be further processed, such as echo canceling, noise reduction and automatic gain control.

Abstract: The present invention provides, in one embodiment, a system and method for concealing video errors. The system includes a coding engine for processing each frame of a video signal to generate macroblocks, selecting a refresh interval based upon network communication parameters, and encoding one or more of the macroblocks as refresh intra-coded macroblocks based upon the selected refresh interval. The refresh intra-coded macroblocks are placed into discrete data packets for transmission across a network to one or more remote devices. Upon receiving other refresh intra-coded macroblocks from a remote device via the network, the coding engine decodes the received intra-coded macroblocks, and places the decoded macroblocks in a newly decoded video frame to be used as reference frame macroblocks for reducing video errors associated with prediction drift.

Abstract: A system and method that provides reliable connectivity of conference calls by ensuring that sufficient network resources are available at the time of the requested conference calls. The system includes multiple endpoints for requesting conference calls, and a gatekeeper bound to a resource scheduler such that requested conference calls are scheduled via the scheduler according to connectivity policies maintained by the gatekeeper.

Abstract: The error concealment technique disclosed herein relates to the use of existing information by the decoder to conceal bitstream errors regardless of what the encoder does. Examples of existing information include, for example, the previous reference frame, macroblock information for the previous reference frames, etc. Another aspect of the system described herein relates to the steps that the encoder can take to enhance the decoder's ability to recover gracefully from a transmission error. Exemplary steps that can be taken by the encoder include intra walk around and sending GOB headers. Although these encoder techniques can provide greatly enhanced results, they are not strictly necessary to the system described herein.

Abstract: A central directory system for a network of dial-up communication devices is described. In a preferred embodiment, the communication devices are videoconferencing devices. The system includes a directory management module coupled to the network and configured for importing and exporting directory information to and from a communication device. The directory information received by the management module can be grouped into address books by an access control module coupled to a database in which the address books can be stored. The access control module is further functional to manage access to the address books. Embodiments of the directory system provide systems and methods for providing intelligent dialing service to the dial-up communication device. A dialing algorithm determines a dialing sequence to connect communication devices through a network based on geographic dialing rules and information related to the requesting device.

Abstract: A system and method particularly useful in handling the video of a “large” conference is disclosed. The system and method initially defines certain conferees as panel members, which can provide input video signals to the multipoint control unit and can receive output video signals or a composite layout for the conference from the multipoint control unit. The system and method also initially defines audience members, which only passively receive the output video signals or layout from the multipoint control unit and do not have their video signals incorporated into the layout of the videoconference. In one aspect, an audience terminal can request to participate in the conference. By making an appropriate request, the audience terminal can, if system resources are adequate, participate fully as a panel member and may supply video signals to the conference for at least some portion of time.

Abstract: A system and method for providing video quality improvement are afforded. A video stream is monitored. A quality of at least one data field associated with the video stream is determined. A command is generated in response to the determined quality of the at least one data field. A video frame is then displayed according to the command.

Abstract: Methods and devices for controlling room function devices from a single conference unit. A conference unit can be a video conference unit or a speakerphone. Controlled devices may include external loudspeakers, microphones, room function controllers, powered doors, powered windows, powered window shades or blinders, video screens etc. The connections between devices may be wired, wireless, or a combination of both.

Abstract: A system and method for determining if a first and second device are co-located includes first and second sensors for receiving a sample signal. Each sensor is coupled to the first and second devices. The first and second devices each responsively generate a first and second signal representing the sampled signal. Also included is a transmission device located at the first device for transmitting the first signal to the second device and a receiving device located at the second device for receiving the first signal from the first device. Finally, a signal analysis device determines if the first and second devices are co-located.

Abstract: The present invention allows higher quality video images to be transmitted without a concomitant increase in a total number of video data bits transmitted per frame. Quantization parameters are applied to coefficients of macroblocks within a given video frame. A lower value of the quantization parameter is applied near a central region of a video frame. This central region is referred to as a prime video region. Applying the lower quantization parameter to the prime video region has the effect of increasing the video data bit density within that area. Outside of the prime video region, the video data bit density per macroblock is decreased so as to have a zero net-gain in bit density over the entire video frame. Furthermore, there may be a plurality of prime video regions where quantization parameters are dynamically coded. In this case, the value of the quantization parameter will increase or decrease within a given prime video region based on a relative importance of a particular prime video region.

Abstract: A conferencing method that conducts an audio conference over the Internet. The method includes receiving digitized audio signals, summing a plurality of received audio signals that contain speech, providing a summed conference signal from the summed plurality of audio signals with an audio conference mixer, transcoding the summed conference signal, and streaming the transcoded summed signal onto the Internet.

Abstract: An acoustic tracking system that uses an array of microphones to determine the location of an acoustical source. Several points in space are determined to be potential locations of an acoustical source. Beamforming parameters for the array of microphones are determined at each potential location. The beamforming parameters are applied to the sound received by the microphone array for all of the potential locations and data is gathered for each beam. The most likely location is then determined by comparing the data from each beam. Once the location is determined, a camera is directed toward this source.