Abstract: An interdiction device and method to jam or delete selected video and telephony signals. The interdiction device includes amplifiers and forward couplers to prevent the telephony signals from appearing at other undesired subscriber locations on the network.

Abstract: A system for creation of user-selected customized audio products, defined as a plurality of songs from different recording artists recorded on a single compact disc (CD) or digital audio tape (DAT) cassette, at record store/distributor locations utilizing a digitized, central database with production hardware at distributor sites. Customized products consist of CD ROM or digital audio tapes (DAT) with music or voice content selected from large digital database, and are written at local workstations at distribution centers (such as record stores) which are connected by a high-speed communications network. The system records costs of the digitized audio (e.g., royalties for individual songs) for billing purposes, as well as producing descriptive material (contents, background information, and graphics for labels, etc.).

Abstract: This invention relates to a video system comprising integrated random access video technologies and video software architectures for the automated selective retrieval of non-sequentially stored parallel, transitional, and overlapping video segments from a single variable content program source, responsive to a viewer's preestablished video content preferences. Embodiments of the video system permit the automatic transmission of the selected segments from a variable content program as a seamless continuous and harmonious video program, and the transmission of the selected segments from an interactive video game further responsive to the logic of the interactive video game. The viewer's video content preferences being stored in the video system, and/or in a compact portable memory device that facilitates the automatic configuration of a second video system.

Abstract: An interactive audio-visual (A/V) transceiver is advantageously coupled to a television and/or telephone (T/T) cable, a TV, a video recorder (VCR), and other A/V devices. The A/V transceiver switches data between a program/service provider and the connected A/V devices. In one embodiment, the transceiver includes three primary modules, a main module including a CPU, a system bus, system memory, an infra-red (IR) control unit, an audio-visual bus, an A/V decoder, an A/V processor, and an A/V encoder, an A/V connect module including a number of tuner/demodulators and a switch, and an optional CD ROM module. The A/V transceiver hardware is complemented with an operating system and software program which supports the functions provided in the A/V user interface.

Abstract: Various methods and associated apparatuses are provided for communicating data from a central station to a remote station over some form of communications path. The data, which together form at least one title, are stored on at least one storage device. The data forming that title are then retrieved as data blocks from storage. Each data block is a sequential segment of the data. Finally, the retrieved data blocks are transmitted from the central station to the remote station. According to preferred embodiments, two types of storage devices are provided. The first type, preferably formed as an array of playback units, allows the data to be stored as data blocks and distributed accordingly over a plurality of storage devices. The second type, preferably formed as ring structures composed of solid state elements, provides a plurality of access points coupled to the storage medium, each of which is able to retrieve the data independently of other access points.

Abstract: A number of domestic audio/video apparatuses (10,12,14) are interconnected by a Domestic Digital Bus (16) for the exchange of control information. A User I/O subdevice (41) in one apparatus is addressable by a control subdevice (22) of another apparatus to allow the display of menu items defined by the control subdevice. The User I/O subdevice returns user control signals by reference to the defined menu items. The right of menu control can be transferred via the User I/O subdevice to and from other control subdevices (20 etc.) to allow integration of the menu control functions of the different apparatuses.

Abstract: A distribution system for audio program materials includes a portable audio storage and retrieval device that is programmable from a high speed data transfer system, and that includes a high-capacity data storage medium, a base control interface for identifying and accepting program material, a mobile control interface for displaying the identity of recorded material for playback selection, a recording mechanism for accepting very high speed digital data from an external source at rates faster than real time, and a playback mechanism for retrieving the stored data from the storage medium and for converting the data into audio signals for playback.

Abstract: A system for composing multimedia signals from various source signals, such as still-frame video signals, full motion video signals and audio signals includes a plurality of composing units, each of which is capable of composing a multimedia signal from selected source signals. One of such composing units is assigned for each multimedia signal to be composed. Each composing unit accepts parameters specifying various properties for each element of the multimedia signal, such as size, position and precedence for each video element and gain for each audio element. The composing units can include decompressors for decompressing source signals furnished in compressed form and a compressor to compress the multimedia signal to be transmitted to a user. The source signals can be received from a packet network and the resulting multimedia signals transmitted to the respective users via the same packet network.

Abstract: An apparatus records and accesses information received over a phone network. The apparatus is part of a system that has a premises phone connected to the phone network via a first communication channel. The apparatus includes a premises recording unit which records information, phone messages and prompts received from the network along the first communication channel. The premises recording unit interfaces with the video display for displaying stored information, telephone messages and prompts. The premises recording unit is responsive to control signals received from a premises phone along a second communication control channel extending between the premises phone and premises recording unit. A switch in the system allows the premises phone to communicate with the network along the first communication channel and also controls the premises recording unit through signal generation by the premises phone through the second communication control channel to the premises recording unit.

Abstract: A satellite broadcast receiving system is disclosed, in which when each receiver transmits a control-pulse to a change-over divider via a signal cable, the change-over divider selects a desired broadcast signal in response to the control pulse, which is led to its output terminal, then transmitted to each receiver via the signal cable.

Abstract: Location specific messages or programming are generally broadcast and selectively filtered by user terminals which have encoded one or more arbitrary locations of interest. The area surrounding a user, a remote location, a route to be travelled, or the like may be selected for receipt of local warnings, local commercial messages, and the like. A set-top receiver being a preferably tunable apparatus capable of receiving digital information transmitted by a variety of means. Transmitted messages contain information targeted to geographical groups of users, with location designation coding accompanying location-specific messages. A geographic location selection code is entered into a data processor coupled to the user's receiver to define the user's selected location(s) of interest. The processor receives the information segment and its designation code and compares the designated location to the selected one. Segments where the designated and selected points or areas overlap are processed. e.g.

Abstract: There is provided a dynamic and adaptable method and apparatus to support two-way multi-media communication services on a multiple access communication system, which comprises a central controller, a shared transmission media and a plurality of remote terminals dispersed throughout the network. The central controller comprises switch and control apparatus and a pool of transmitters and receivers. The communication channels between the central controller and remote terminals are arranged for signalling data and traffic bearer channels in the forward and reverse directions. The number of signalling data channels is adjusted to satisfy the traffic requirements and for redundancy purposes. The forward and reverse signalling data channels are coupled in different mappings to support terminal grouping. Multiple access of the remote terminals for the upstream traffic are mitigated by separating remote terminals in groups via the channel allocation and the terminal assignment process.

Abstract: The oscillator at the sending node of a wireless digital network, generates a carrier signal, starting at a first instant. A modulator coupled to the oscillator performs phase shift modulating of the carrier signal with an input signal. A spoiler signal generator is coupled to the modulator, for providing a spoiler signal as the input signal, starting at the first instant and continuing for a first duration which is longer than a period needed for the oscillator to achieve stable characteristics. A transmitter is coupled to the modulator at the sending node, for transmitting a wireless radio signal representation of the carrier signal phase shift modulated with the spoiler signal to a receiver at a receiving node. The spoiler signal in the modulated carrier signal interrupts the periodic characteristic of the pulses, and thereby prevents the carrier sensor from detecting the carrier signal.

Abstract: Method and apparatus for providing a receiver a high quality video signal and a plurality of lower quality video signals which can be zapped, i.e., searched through at any given time, via a channel having a limited data capacity. A first set of high quality video signals is present at a transmitter, e.g., fifty programs having a 10 Mbit/s data rate. A second set of video signals which is a subset of the first set of video signals is sent to the receiver in response to a control signal which indicates the programs a viewer has selected to be viewed at high quality, e.g., using the full 10 Mbit/s of data. A third set of video signals is also sent from the transmitter to the receiver. This third set of video signals represents low quality programs, e.g., signals having a 1 Mbit/s data rate, which can be searched.

Abstract: An interactive television information system having a node in television communication between a source of television information services and a plurality of home interface controllers. Each subscriber television is associated with a home interface controller. The home interface controllers receive the television information signals and include a data transceiver for data communications with the node. Express trunks deliver television information services to groups of subscribers. Each trunk includes a first bandwidth portion for carrying broadcast television signals in the same manner on each trunk. A second bandwidth portion carries television information services on a demand basis. The node responds to subscriber requests by selecting television information services for delivery over the second bandwidth portion of the express trunk coupled to the requesting home interface controller.

Abstract: A distribution center according to the present invention is capable of handling requests from a plurality of subscribers for accessing programs in a central audiovisual library. The subscriber requests may specify a variable time allowance interval within which a requested program may be delivered.

Abstract: An interactive television information system coupled to a cable television system having a headend for supplying information services and an information service distribution network for delivering information services to subscriber televisions. Each subscriber television is associated with a home interface controller. The home interface controllers receive the television information signals and include a data transceiver for data communications. A subscriber selection device associated with a home interface controller permits subscriber interaction through the data transceiver with an assigned interactive controller from a plurality of interactive controllers. The assigned interactive controller is in communication with the information sources and in television communication with its assigned home interface controller. Selection of an information source nay be made through channel selection of an apparent channel from any of a first group of apparent channels and a second group of apparent channels.

Abstract: A system of distributing video and/or audio information employs digital signal processing to achieve high rates of data compression. The compressed and encoded audio and/or video information is sent over standard telephone, cable or satellite broadcast channels to a receiver specified by a subscriber of the service, preferably in less than real time, for later playback and optional recording on standard audio and/or video tape.

Abstract: The present invention provides a user programmable entertainment method and system that provides varied and ongoing custom entertainment services. The method of the present invention provides an entertainment signal comprising a sequence of discrete expressive works to an end user. The discrete expressive works represented in the entertainment signal may be either specifically requested by the user or selected according to user-specified parameters. According to the present invention, a user defines a sequence of user preference items which together comprise a user preference signal. The user preference signal is then communicated to a remotely located program processor. The program processor selects a plurality of discrete expressive works that conform to the user preference item definitions. An entertainment signal comprising the selected expressive works is then communicated over a communication link to the receiving means located in the user node.

Abstract: A system is disclosed for delivering audio and/or video signals to users in connection with the provision of interactive television services. Various sources of such signals are connected to a digital network, such as a packet network. Also connected to such network are control and application processors and interfaces to distribution arrangements such as cable television systems and telephone subscriber loops. Each user has a signal converter for receiving a digital signal from the distribution arrangement, converting such signal for viewing on a conventional television receiver and transmitting control packets to other elements of the system. The signal sources can include a data cache for storing recorded video and audio materials, a broadcast source for receiving broadcast signals, apparatus for composing multimedia signals from multiple sources and apparatus for running games.

Abstract: In a video on demand system utilizing asymmetric digital subscriber line (ADSL) interfaces, a plurality of video channels are arranged at a central office into ADSL format and, together with a provisioning channel, are multiplexed into a composite spectrum. This composite spectrum is then transmitted to an intermediate distribution point, remote from the central office, over analog optical fiber. The composite spectrum is split and applied individually to channel selection mixers associated with the subscribers serviced by the intermediate distribution point. Telephone signals (POTS) are combined at the intermediate distribution point into the ADSL signal and transmitted with the video, to an ADSL multiplexer/demultiplexer at the subscriber's location. In the reverse direction, channel direction/change signals are split from the composite received from the subscriber's location at the intermediate distribution point and utilized to control channel selection.

Abstract: A communication system is provided for the distribution of switched video, along with telephony and control information, over fiber from a central office to a subscriber premises. The system can dynamically allocate video channels to subscribers using a pool of switched channel selector units located at the central office, thus permitting increased sharing of video distribution resources and controlling access to all channels. The system can provide a multiplicity of simultaneously available switched channels at each subscriber premises from a selection of over a hundred channels available at the central office. Subscribers are connected to the switched video service through a switched video distribution system rack. Switched channels will travel over single-mode fiber in AM/VSB format compatible with subscriber video equipment.

Abstract: The present invention relates to a video server (DS) for transmitting video signals (VS) to user stations in response to the receipt of control signals issued by these user stations and including a plurality (HDA) of memories (HDASA, HDASB) which are controlled by a plurality of memory controllers (OBC, SCSIC-A/B). The memory controllers are controlled based on the control signals by a server control means (DSC, PCM1/PCMN) which includes a server controller (DSC) and a plurality of program control modules (PCM1/PCMN) each of which is associated with a subset (HDA1/HDAN) of the plurality (HDA) of memories (HDASA, HDASB) and to a subset of the plurality of memory controllers (OBC, SCSIC-A/B).

Abstract: A public switched telephone network for providing information from a multimedia information server to any one of a plurality of subscriber premises, comprises a central office receiving multimedia information signals from a multimedia information server and orders from a prescribed subscriber. The central office includes a gateway system for conveying routing data in response to subscriber orders and a switch for routing multimedia signals from the server to the prescribed subscriber in accordance with the routing data. An interface at the central office transmits and receives audio telephone service signals, subscriber control signals and digital multimedia information signals on first, second and third signal channels. Each subscriber premises includes an interface for transmitting and receiving audio telephone service signals, subscriber control signals and digital multimedia information signals on the three signal channels.

Abstract: An interactive video services system for enabling store and forward distribution of digitized video programming is disclosed. In accordance with a feature of the present invention, encoded and compressed digital video signals are transmitted via satellite link from a centrally located uplink site to a plurality of hospitality establishments, where the digitized video programming is stored in the memory of a video server computer or is transmitted "real-time" to the hospitality establishment's customers. The establishment either has its own downlink facilities or shares downlink facilities with other hospitality establishments. The uplink facility and satellite can transmit a variety of video signals - including video signals for real-time viewing by customers, compressed video signals for storage and subsequent retrieval and viewing by customers, and other types of digitized data, such as advertisements and barker screens.

Abstract: A plurality of movies are distributively stored in digitally encoded form on a mass storage unit such as a Redundant Array of Inexpensive Drives (RAID) disk drive array such that they can be viewed on demand by multiple users. A video server receives movie requests from users, and retrieves and transmits the requested movie data from the RAID array to processors at the respective user locations. The processors decode the retrieved data to produce video picture and audio information and display the corresponding movies on monitors. Temporal instantaneous digital data rate signatures for the movies are computed and stored, and a current composite signature is computed by summing the signatures for all movies currently being shown. When an additional movie is requested, the signature for the additional movie is combined with the current composite signature to produce a new composite signature.

Abstract: A program table displaying apparatus includes a display controlling apparatus for displaying a program table for a plurality of programs in a table on a display. The table has a horizontal row with a channel number identifying a channel corresponding to one of the programs and a vertical row with a time number for the channel. The television program table is derived from a plurality teletext broadcasts. Also included is a program reserving apparatus for reserving a desired program by selecting one of the programs. A time comparing apparatus is further provided for comparing a current displayed time frame and the time number for the channel to determine if there is a corresponding program for the displayed time frame. Further provided is a minute information extracting device for extracting minute data corresponding to said corresponding program.

Abstract: Upstream transmissions in a two-way communications network are effected from subscriber terminals in upstream packets having one of a plurality of different separately acknowledgeable acknowledgment tags. Downstream acknowledgments of upstream messages are contained in CA packets multiplexed with product packets to form a transport bitstream. The transport bitstream is applied to a digital conditional access module (DCAM) in the terminal which is controlled by the conditional access data bits of the CA packets. The DCAM includes a status register for storing the acknowledgment bits of the CA packets, which bits are coupled by a microprocessor for controlling the upstream transmitter.

Abstract: A method and system for providing programming on demand service to television subscribers. In a preferred embodiment, each group of viewers that requests a given program is coupled to a separate video "feed" of the program. Each individual feed shows the program at a different rate. In this manner a second group of viewers who begin viewing a program after a first group of viewers may "catch up" to the first group. Whenever such an "intersection" occurs, the groups are merged and view the remainder of the movie on a single feed. In this manner the total number of feeds to required to provide video on demand service to a large number of viewers is reduced.

Abstract: In a telecommunications system providing switched video services, a video line card includes a switch arrangement for selecting a plurality of channels from a greater plurality of available channels and for providing said selected channels in a fixed bandwidth that may be received by a subscriber. A plurality of tuners are used to select the channels and to provide the channels on an intermediate frequency, which frequency is thereafter converted to a distribution channel frequency acceptable by the subscriber.

Abstract: A video information distribution system allows users to call a video center and receive required video information from the video center through high- and low-speed transmission lines. The system employs trunk units. The trunk units are arranged in the video center or between the video center and the users, to receive video information repeatedly transmitted at high speed through the high-speed transmission lines. The trunk units reproduce the received video information at normal speed and transmit the reproduced information to the users through the low-speed transmission lines. Each of the trunk units has a reproduction memory, a fast-forward memory, and a rewind memory to provide the users with reproduction, fast-forward, and rewind functions similar to a video deck.

Abstract: A multifunction microwave modulator circuit has an input signal splitter to provide two equal amplitude signal components. A phase quadrature relationship between the two signal components is obtained by constructing the splitter as a Lange coupler. There is pair of circuit cells, each of which operates separately on one of the two signal components to electronically adjust a vector representation of the signal to provide a vector having a desired amplitude, ranging over both positive and negative values of amplitude, including zero amplitude. The signal vectors of the two cells are combined by means of a Wilkinson combiner to provide an output signal represented by a resultant vector which may have any direction within 360 degrees, and an amplitude scale factor which varies from unity to zero.

Abstract: The invention provides a method and apparatus for transmitting information recorded on a collection of digital disks from a central server via a high data rate digital telecommunications network to subscribers connected to the network. Apparatus of the invention includes a central server (1) connected via an interface (5) to a digital telecommunications network (2) to which subscriber stations (3) are connected. The server center includes a central computer (4), a digital disk magazine (7), digital disk players (10.sub.1, 10.sub.2, . . . , 10.sub.n) and disk transferring equipment between the magazine and the players, which includes a conveyor (8) and a disk handling device (50) controlled by a disk controller (6) itself controlled by the central computer. One application delivers personalized sound programs selected from a very large directory to the subscribers.

Abstract: An interactive arborescent architecture teledistribution network includes an exchange controlling the transmission of television programs, images and sound programs and a wide band source for transmitting all these programs. A user differentiating circuit box is used as well as a circuit to interrogate the user differentiating circuit box, a circuit to transmit a program request from the user for the exchange once the box of the user has been addressed by the exchange, circuits in the exchange for generating a validation signal in response to the request, and circuits disposed in the user differentiating circuit box so as to select a program from all the programs transmitted according to the validation signal. The user differentiating circuit box is preferably disposed on the arborescent architecture between the exchange and the television receiver of the user.

Abstract: For fiber-to-the-curb program switching, which is done at the central office, the same fixed frequency slot is always used for distributing the TV program selected for a video recording device at the subscriber's premises; for its related display, another selected slot is always used for distributing another selected TV program; the set-top converter is provided with two narrow band filters, one for each dedicated slot, instead of expensive tuners; the same set-top converter can be used in other rooms of the subscriber premises, except using a plug-in tuner for placing additional selected TV programs received from remaining, nondedicated slots into the same filter band used for the TV associated with the video recording device.

Abstract: A phase modulator circuit and method for generating an output signal having individually positionable edges is described. The phase modulator includes a programmable pulse generator, such as an interval counter, or a delay for producing the output signal, and a control value source, such as a memory, for delivering a sequence of control values to the generator. The control values determine the time between successive output pulses.

Abstract: In a video distribution system, methods and apparatus for rapid channel selection are implemented to reduce the channel-to-channel latencies which might otherwise occur in modern video decoding systems, such as MPEG-2. In addition, methods and apparatus are implemented for providing fast forward, fast reverse and channel pause functionality when utilizing staggered start times for a particular program source.

Abstract: Apparatus for providing a user friendly interface to a subscription television terminal comprises a key pad arranged into a plurality of key groupings and an on-screen display controller for generating a plurality of screens for display on an associated television receiver. Five such key groupings are segregated from one another and comprise function keys, initialization keys, channel keys, audio keys and digit keys. The digit keys may be most conveniently arranged in a two dimensional matrix corresponding to a key pad of a conventional tone dialing telephone. Each of the other key groupings may be arranged linearly and differentiated by the use of color or boxes. A method of initializing the cable television terminal comprises the steps of generating a display of a menu structure, actuating the movement of a cursor in one direction through choices presented by a menu by use of a cursor key, and actuating a selection of a menu choice via actuation of a select key.

Abstract: A method and system for determining the required number of active video circuits in an interactive video delivery network required to meet the specified blocking probability constraints. By determining peak loading hours as well as the number of system subscribers in a given video delivery network, the user may determine the blocking probability of the interactive video delivery system in accordance with the formula: ##EQU1## This information may thereafter be used to determine the number active video circuits to meet the determined blocking probability.

Abstract: An improved audio-visual computer-based home entertainment media inventory and control system is disclosed comprising a computer with associated software, for controlling any combination or number of video tape record-playback units, audio tape record-playback units, video disc record or playback units, CD audio record or playback units, and the like, said system includes a touch-screen color video display for displaying computer or TV format graphics, inventory lists, and operational touch screen menus for ease of operator use in inventorying and accessing audio-visual recordings. This system includes hardware and software facilities for accessing electronic mail sources of media content information, graphics data and broadcast air time guides.

Abstract: An inductor transmission path for energy and data from a write/read station onto, for example, a chip card is disclosed. A specific, vector-oriented phase modulation with two coils is disclosed, making it possible for the write/read station to use the same method to service different cards, i.e. those with one coil, or with a large coil or having two coils.

Abstract: A PLL circuit modulatable by a modulation signal having a direct current component has a voltage-controlled main oscillator, a loop divider, a phase comparator and a loop filter. The reference frequency signal for the phase comparator is derived from the modulation signal by a first compensation filter, a voltage-controlled reference oscillator and a reference divider being connected downstream of said first compensation filter. The voltage-controlled main oscillator is controlled by the modulation signal via a second compensation filter followed by a downstream data lowpass.

Abstract: A system and method of supporting pause-resume in a video-on-demand service of a type which can accommodate multiple viewers sharing a common data stream is described. When a video server receives a performance request from one of the viewers for showing a particular video, it identifies and reserves a look-ahead stream. The look-ahead stream is another video stream which is scheduled to become available after a predetermined time period. When the video is commenced, a common data stream for the video is concurrently transmitted from the video server to reception equipment at the viewers' locations. Transmission of the common data stream causes the particular video to be performed on the viewers' reception equipment. When the video server receives a pause request and then a subsequent resume request from one of the viewers, it transmits the video via the look ahead stream instead of the common data stream.

Abstract: A pay-per-view system for a cable television network that gives the subscribers a greatly enhanced variety of viewing choices. The system uses an interactive set top box for the subscribers to forward their choices for viewing. Since the pay-per-view viewing choices are made interactively from a wide variety of selections, the chances of a subscriber finding something he or she wants to pay to watch are considerably improved. The interactive choices are forwarded to an intelligent video switch. This switch takes the first N programs requested and assigns N programmable selectors to select N programs from a much greater number (M) of possible programs and switches these N programs onto N frequency multiplexed channels on a standard television cable.

Abstract: A phase modulator for a microwave band having a desirable modulation characteristic by maintaining the impedance thereof constant, includes two PIN diodes 2 and 3 connected to a merchant balun 1 and a bias circuit 18 which supplies bias voltages to the PIN diodes 2 and 3 such that the sum of the bias voltages applied to the diodes 2 and 3 is constant. The bias voltages are selected so as to have the input and output impedances to be in the most stable state when a modulation signal is equal to zero.

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 digital adjustable phase modulator and method includes a first circuit path and a second circuit path for a signal. A fixed bias voltage is coupled to the first circuit path and to the second circuit path which respectively include first and second active variable reactance components such as varactor diodes. The first circuit path and the second circuit path further include chip capacitors to provide a DC block for first and second MMIC single pole double throw switches, and transmission lines for the signal have a length of one-fourth of a wavelength of the signal to provide an RF short. A control voltage is coupled to the first and second varactor diodes such that the capacitances across the first and second varactor diodes changes, resulting in a phase difference between the signal traversing the first circuit path relative to the signal traversing the second circuit path.

Abstract: An integrated scheduling approach that provides VCR control functions to clients without always requiring a separate video stream for all clients. When a client invokes a resume, following a pause, the system uses a hierarchy of methods to handle the request. If an ongoing video stream is available such that the point at which the client is paused will be reached by that stream within a tolerable delay, the client is assigned to the ongoing stream. If no such stream is available, and the client request can not be served from a buffer, the system assigns the client to a reserve stream taken from a pool of reserved server capacity. If no reserved server capacity is available, the client is given priority for assignment to the next stream to become available.

Abstract: Different components of television programs, such as the video and audio components or different time segments of the program, are assigned to different channels transmitted in the form of packetized digital information in at least one of the channels of a multi-channel cable television distribution system. A particular subscriber's converter is configured to receive a particular subset of program components by enabling the converter to receive the virtual channels carrying the components in such subset. An embodiment is disclosed in which different combinations of program segments are enabled for different subscribers. Another embodiment is disclosed in which the viewing of a program by multiple subscribers who begin viewing at different times is synchronized by using "filler" program segments having different lengths.

Abstract: The invention relates to a system for transmitting stored programs, such as movies and musical works, to customers via a distribution network, such as a cable television system. The programs are stored in compressed form in a program library, such as a tape cartridge library. On receipt of a request for a program, a request processor sends control messages causing a data block comprising the requested program to be read from the program library at high speed and stored in a large dynamic random access memory (DRAM) in a server. The server then sends the program from DRAM over the distribution system to a customer as a series of digital packets. Each instance of sending a program is managed by a separate command word. The customer can request such operations as "fast forward" by sending control messages that change pointers in the command word. Command words can be grouped to send multiple audio and/or video overlays simultaneously and linked to send program sequences.