Abstract: The present invention is directed to a videophone system implemented over a cable television network. The instant invention provides a videophone comprising a camera for capturing images associated with a videophone signal, a videophone unit and a set top terminal or cable modem connecting the videophone to a cable television network. Videophone signals created at the call origination site are encoded and transported to a predetermined destination over an existing cable television network. The system uses IP addresses as phone number on the network. Additionally, transport of videophone signals between different cable systems is accomplished via a high-speed long distance data network, such as, for example, a satellite network, that provides communication between the headends of the different cable television systems. The set top terminal may be a conventional subscriber terminal, a cable modem or a subscriber terminal configured to operate as a cable modem.

Abstract: Techniques are provide herein to determine the amount of allocated and unutilized bandwidth for services already provided on each of a plurality of quadrature amplitude modulator (QAM) channels. One of the plurality of QAM channels is selected as a selected QAM channel to maximize capacity for future service requests based on a determination that the selected QAM channel can have bandwidth deallocated to support a service at a second bandwidth greater than a first bandwidth. A sufficient amount of the allocated and unutilized bandwidth is deallocated for services provided at the first bandwidth on the selected QAM channel such that the service at the second bandwidth is thereafter supportable on the selected QAM.

Abstract: Channel changes between services with differing bandwidth in a switched digital video system. A services map published by the headend and distributed to all of the edge devices, allows a bandwidth requirement to be correlated with each request from a device in the home. The bandwidth requirement is passed upstream along with the request for service and is subject to a system resource management validation.

Abstract: Quality of service management in a switched digital video environment. The devices in a user's home can be given quality of service priority statuses by a system operator. In the event of oversubscription, the quality of service management allows the user to determine which services will have priority over others if more bandwidth is requested than available.

Abstract: A device in a subscriber television system receives a stream of frames of information, and each frame of information is carried in at least one network packet that is formatted according to a first protocol. Each network packet carries an application packet that is formatted according to a second protocol, which is a protocol for an application. The device includes application awareness that enables the device to selectively modify the application packets.

Abstract: The present invention is directed to a videophone system implemented over a cable television network. The instant invention provides a videophone comprising a camera for capturing images associated with a videophone signal, a videophone unit and a set top terminal or cable modem connecting the videophone to a cable television network. Videophone signals created at the call origination site are encoded and transported to a predetermined destination over an existing cable television network. The system uses IP addresses as phone number on the network. Additionally, transport of videophone signals between different cable systems is accomplished via a high-speed long distance data network, such as, for example, a satellite network, that provides communication between the headends of the different cable television systems. The set top terminal may be a conventional subscriber terminal, a cable modem or a subscriber terminal configured to operate as a cable modem.

Abstract: Atomic channel change in a switched digital video (SDV) system. A set-top box (STB) sends join and leave message commands to a SDV device when requesting a channel change. If one of the IGMP message commands does not reach the SDV device, oversubscription can occur. A combined join and leave message ensures that a join command is performed only when a leave command is also performed. If the single message does not reach the SDV device, the STB resends the command.

Abstract: Channel changes between services with differing bandwidth in a switched digital video system. A services map published by the headend and distributed to all of the edge devices, allows a bandwidth requirement to be correlated with each request from a device in the home. The bandwidth requirement is passed upstream along with the request for service and is subject to a system resource management validation.

Abstract: Quality of service management in a switched digital video environment. The devices in a user's home can be given quality of service priority statuses by a system operator. In the event of oversubscription, the quality of service management allows the user to determine which services will have priority over others if more bandwidth is requested than available.

Abstract: Partial pre-encryption with network-based packet sorting. A video-on-demand (VOD) delivery system for delivering encrypted transport streams to incumbent and overlay set-top boxes utilizes a packet picker/duplicator for sorting selected packets from non-selected packets, duplicating the selected packets, and encrypting one of the pair of duplicated selected packets according to an incumbent encryption scheme. A VOD file server stores the transport stream from the packet picker/duplicator. A network sorter sorts the unencrypted selected packet from the non-selected packets and the encrypted selected packet. The network sorter also sorts the encrypted selected packet from the non-selected packets and encrypts the unencrypted selected packets and the non-selected packets according to an overlay encryption scheme and then sends the transport stream to an overlay set-top box.

Abstract: A device in a subscriber television system receives a stream of frames of information, and each frame of information is carried in at least one network packet that is formatted according to a first protocol. Each network packet carries an application packet that is formatted according to a second protocol, which is a protocol for an application. The device includes application awareness that enables the device to selectively modify the application packets.

Abstract: This invention provides a method for a subscriber television system client device to provide a three-dimensional user interface comprising a virtual reality media space. The three-dimensional user interface allows the user to navigate a three dimensional environment, participate in activities, and interact with other users. The three-dimensional user interface enables the user to associate personal characteristics with an avatar which represents the user in the system, such personal characteristics comprising a symbol, a picture, and video.

Abstract: A system for recalling surfed channels includes functionality that stores identifications of surfed channels and recalls each of the surfed channels in response to a user pressing a button on a device.

Abstract: This invention provides a method for a subscriber television system client device to provide a three-dimensional user interface comprising a virtual reality media space. The three-dimensional user interface allows the user to navigate a three dimensional environment, participate in activities, and interact with other users. The three-dimensional user interface enables the user to associate personal characteristics with an avatar which represents the user in the system, such personal characteristics comprising a symbol, a picture, and video.

Abstract: A user is provided with an interactive program guide identifying future television programs that are scheduled to be broadcast at a later time. After the user selects a future television program, the user is provided with the future television program in advance of its scheduled broadcast time.

Abstract: A graphical user interface for a videophone in a cable television system allows the user to access the videophone functionalities with an input control device and a television monitor. The user can place a call, receive a call and store/access/call addresses using a remote in conjunction with the graphical user interface display screens. The videophone has several elements including a user interface, a graphics engine, a network interface, a remote control interface, and an output audio/video line connected to a television monitor. The user interface receives and processes control inputs using a microprocessor and the graphics engine generates the display screens using a DSP. Depending on processing requirements, the DSP may implement the user interface rather than the microprocessor. Also, anti-aliasing fonts are used to generate a high quality display. To save processing cycles, the anti-aliasing fonts may be retrieved from a look-up table rather than being generated in real time.

Abstract: A remote control system including a hand held remote control unit with an alphanumeric information display, for controlling and communicating with a first controlled device, such as a digital music tuner connected to a community antenna television (CATV) cable, and for controlling a selected one of a plurality of second controlled devices, such as CATV set-top units, VCRs, or television sets. A first, high speed, error free display information communications protocol is utilized for transmitting program content or other information from a device, such as the CATV-connected music tuner, to the remote control unit for display. A second or control communications protocol is utilized by the remote control unit for controlling the first controlled device and a selected one of the second controlled devices. The CATV cable-connected music tuner utilizes the 44.

Abstract: An apparatus and method is described for transmitting, receiving and communicating program data signals which are combined with digital data signals. Preferably, the present invention compresses 30 digital audio signals, multiplexes them with title, track, artist, record label, year, etc., program information, and transmits the combined signals via satellite to a receiving station. The receiving station demultiplexes the signals and sends them via a cable distribution system to a subscriber's digital music tuner. This tuner further demultiplexes and decodes the signals so that the digital audio signals may be converted to analog and output for listening, while the corresponding data signals are communicated to the subscriber. In an alternative preferred embodiment, the program data signals are transmitted to a remote control receiver where they are displayed. The system described in the present invention may be used for transmitting video, software or games with program data to subscribers.

Abstract: A remote control system including a hand held remote control unit with an alphanumeric information display, for controlling and communicating with a first controlled device, such as a digital music tuner connected to a community antenna television (CATV) cable, and for controlling a selected one of a plurality of second controlled devices, such as CATV set-top units, VCRs, or television sets. A first, high speed, error free display information communications protocol is utilized for transmitting program content or other information from a device, such as the CATV-connected music tuner, to the remote control unit for display. A second or control communications protocol is utilized by the remote control unit for controlling the first controlled device and a selected one of the second controlled devices. The CATV cable-connected music tuner utilizes the 44.

Abstract: A multiplication circuit for use in an FM television transmitter and receiver is provided. The multiplication circuit includes a limiting circuit for limiting a subcarrier supplied thereto and a dividing circuit coupled to the limiting circuit and dividing the output of the limiting circuit by a predetermined factor. A mixer is coupled to the dividing circuit and mixes the output of the dividing circuit with the subcarrier.