Abstract: A method and apparatus for bit rate allocation, or statistical multiplexing, in a multi-channel video data encoder. A pre-processor in each channel determines a bit rate need prior to compression and encoding. A control processes the bit rate need in each channel to arrive at an allocated bit rate for each channel. The video data is then compressed and encoded according to the allocated bit rate. The bit rate demand accounts for various characteristics of the current picture data in each channel, including spatial activity, temporal activity, image size, frame rate, scene change, brightness, flash, fade, and horizontal pixel resolution.

Abstract: Duplicate participants (e.g., cloned subscriber units) (274) are detected in a communication network, such as a hybrid fiber/coax (HFC) cable television network or the like, by monitoring the physical layer of the network to detect transmission differences between such units. The subscriber units (14, 16, 18, 274, 276) may be cable modems that transmit upstream signals with associated identifiers to a headend (10, 200), e.g., to access the Internet or for telephony. Measured characteristics of the upstream signals can include: (1) propagation time (235), (2) frequency (240), (3) power (245), and (4) spectral characteristics (250). For propagation time, the reception time of the upstream message can be compared to a headend clock (215) and also to other messages with the same modem ID. For spectral characteristics, adjustment coefficients can be provided to the units to normalize the spectrum of the upstream signal to a baseline spectrum.

Abstract: A feature-rich transport multiplexer and a number of associated methods, systems, subsystems, software features, graphical user interfaces and control systems are disclosed. The disclosure includes GUI's that enable operators to easily monitor and manipulate content streams flowing through a transport multiplexer in real-time. The disclosed interfaces include screens that supply operators with identity, structure, configuration, bandwidth utilization and/or status information for system hardware and software. The disclosed features also provide computer assisted routing configuration for present and future routing events through simple manipulation, such as drag and drop operations, of graphical objects. Routing control is further simplified by permitting operators to configure routing control of individual content stream components as well as groups of such components simultaneously.

Abstract: Method and system for providing client privacy on the Internet when the client requests content from a public application server. The method is well-suited to key management protocols that utilize the concept of tickets. The client name or identity is encrypted in all key management messages where the client is requesting a ticket for a specific application server. The key management messages are between the client and a key distribution center (KDC) and between the client and the specific application server. The KDC does not provide the client name or identity in the clear in such messages. This prevents the client's identity from being linked with the content provided by the specific application server, which results in improved user privacy.

Abstract: Communication between a burst manager and plural remote terminals over a first passive optical network (PON) and a second PON, with each PON having a downstream portion and an upstream portion, includes transmitting a common synchronization signal from the burst manager to the plural remote terminals over both downstream PON portions and transmitting burst data from the plural remote terminals over both upstream PON portions to the burst manager. The burst data for each remote terminal is delayed on the first and second PONs by corresponding first and second delays.

Abstract: A method and system of transform-based encoding, decoding, and bitstream generation of digital video content. The digital video content comprises a stream of pictures, slices, or macroblocks which can each be intra, predicted or bi-predicted pictures. The pictures, slices, or macroblocks comprise blocks of pixels. The method comprises scanning frequency coefficients from each of the block's two dimensional array of frequency coefficients in a manner that is vertically biased.

Abstract: A system, device, and method for initial ranging that dynamically adjusts the backoff window size to maximize the probability of success during contention access. The invention takes a first system performance measurement using a first backoff window size, a second system performance measurement using a second backoff window size different than the first backoff window size, and determines a third backoff window size based on the first and second system performance measurements.

Abstract: A system for efficient bit plane coding of transform coefficient data, such as DCT data used in a video coding system. Decimal values for the transform coefficients are converted to binary values, where each bit occupies a corresponding bit plane, from the most significant bit to the least significant bit. One bit from each coefficient is provided in a common bit plane. A one-bit flag or codeword is used for coding one or more initial all-zero bit planes, while another one-bit flag is used for designating the first subsequent non-all-zero plane. For the first non-all-zero plane, a reduced coding table is used to provide codewords that follow the one-bit flag.

Abstract: A Residential Gateway (RG) for distributing video, data and telephone services to multiple devices within a residence is disclosed. The RG receives signals from a telecommunications network, converts the signals to formats compatible with the multiple devices, and transmits the appropriate signals to the appropriate devices. Wireless remote control devices (RCs) associated with remotely located televisions (TVs) transmit channel select commands to the RG as wireless signals. The wireless signals are received by Remote Antennae Packages (RAPs) coupled to the remotely located TVs. The RAPs transmit the wireless signals over coaxial cable to a Media Interface Device (MID) coupled to the RG. The MID extracts the channel select commands and forwards them to the RG. The MID is also capable of combining and splitting TV signals, and adjusting the impedance of network signals so that they can be transmitted over the coaxial cable.

Abstract: A method and apparatus are provided for controlling the quantization level in a digital video encoder that comprises a plurality of parallel compression engines (12). The input picture is partitioned into a number of panels (10) and each panel is processed by a distinct compression engine (12). A reference quantizer scale is determined before encoding a frame of video. The reference quantizer scale is used at the first slice of every video image panel being processed by the video encoder. The quantizer scale at the last slice of the image panel is then forced to be the same as the first slice. The forcing step can use a piecewise-linear feedback formula. A group of pictures (GOP) target bit rate is adjusted based on the number of film pictures and non-film pictures currently in the processing pipeline of at least one of the compression engines. A higher target bit rate is provided for non-film pictures. A buffer (16) level of the video encoder is used to control the start of a new group of pictures (GOP).

Abstract: Still picture images are encoded and transmitted at reduced rates using the MPEG-2 standard. Video frames are captured for processing at a still picture capture rate that is lower than the video input frame rate. The captured frames are compressed as Intra frames at the input frame rate. Selected ones of the compressed frames are inserted in the MPEG-2 transport stream for communication to a decoder at a still picture repetition rate which is no less, in frames per second, than the capture rate.

Abstract: Methods and apparatus for rate control in a dual pass encoding scheme are provided. A first pass encoder encodes alternate slices of anchor frames as I-slices and P-slices respectively in order to generate statistics for both I and P frame encoding for the same anchor frame. An initial complexity estimate for encoding a current frame is determined by the first pass encoder based on statistics from first pass encoding of the current frame and from first pass encoding of a prior encoded frame. A second pass encoder estimates an encoding complexity for the current frame based on the initial complexity and statistics from second pass encoding of the prior encoded frame. The second pass encoder then determines a bit budget for second pass encoding of the current frame based on the encoding complexity.

Abstract: Methods and apparatus for the generation of a cryptographic one way function (a key or keystream generator) for use in encrypting or decrypting binary data. A non-linear key or keystream generation algorithm using multiple feedback shift registers is provided. The feedback shift registers may be constructed utilizing an advanced mathematical construct called an extended Galois Field GF(2m). The key or keystream is generated as a non-linear function of the outputs of the multiple feedback shift registers, which may be a combination of static feedback shift registers and dynamic feedback shift registers. Dense primitive polynomials with many coefficients may be used to produce a cryptographically robust keystream for use as an encryption or decryption key.

Abstract: A system that allows service providers, consumer electronic (CE) manufacturers or standards bodies to define flexible security policies (110) for the execution of downloaded applications (120) on digital television (DTV) receivers (160). The current receiver environment in which a software application is to be run is evaluated. For example, environmental factors such as time of day, date, channel currently tuned in, parental lockout status, grouping of major and minor virtual channels, and so forth, may be considered. An access controller (168) determines if the receiver's environmental factors satisfy the conditions for granting a permission to a downloadable application to allow access to the receiver functions (161), receiver resources and user private data. The security policy can be modified by installing or downloading a new security policy (110), or modified by a user with the provision of an appropriate interface. A Java code-implemented embodiment is disclosed.

Abstract: Methods and apparatus are provided to produce a plurality of different rate output bitstreams from a common input bit stream. Overhead data is extracted from the input bit stream. The input bit stream is partially decoded. Thereafter, the at least partially decoded bit stream is re-encoded at different rates, to produce multiple re-encoded bit streams having different rates. The overhead data is combined with each re-encoded bit stream, thereby providing multiple versions of said encoded bit stream at different rates.

Abstract: A method and apparatus for quality of service localization within a relatively time-invariant communications network, the method comprising the steps of: receiving quality of service estimations for a plurality of communications mediums, wherein each of the plurality of communications mediums is defined between a respective one of a plurality of transmitters located within the communications network to a common receiving point of the communications network, wherein each communications medium is conveyed over at least one shared physical communications path and at least one non-shared communications path; and comparing the quality of service estimations for the plurality of communications mediums with one another in order to localize a respective quality of service estimation to a likely physical communication path within the communications network.

Abstract: An enhanced telephony services manager is used in a broadband communication environment, such as with a set-top-box coupled to a television monitor. A number of different telephony-based services can be offered and displayed on the television monitor (e.g., voice mail, call logs, Internet access, personal telephone directories, white pages, yellow pages, etc.), where a remote control, keyboard, or any other suitable interface device can be used to access the services. In accordance with the present invention, the GUI of the enhanced services consists of a set of menus that can be displayed concurrently with other video information on the television monitor.

Abstract: The present invention encompasses a method and apparatus for ingress detection and attenuation. When a determination is made that the level of ingress in a return frequency band has exceeded a predetermined threshold, the return path is attenuated or disconnected at a communications gateway device located at or substantially near the subscriber location. By disconnecting the return path or attenuating the return path signal at or near the subscriber location, ingress is reduced and locations which are the cause of severe ingress are effectively isolated. This allows for a high degree of reliability to be maintained on the return path, and insures that critical services like cable telephony can be provided.

Abstract: An interactive video/computer pointing system utilizing a magnetic sensor to derive relative azimuthal information, and an inclinometer or accelerometer to provide relative angular elevation information. The azimuthal information is processed to yield an indication of any horizontal movement of the pointing device, and the angular elevation is processed to yield an indication of any vertical movement of the pointing device. This horizontal and vertical movement information is utilized to responsively control a video cursor, thereby enabling the user to point to and select various regions upon a video screen by manipulating the pointing device.