Abstract: A method and system enables the selective addressing of groups of broadcast receivers within part of a satellite footprint. It uses two satellites having a common transmission band to transmit respective signals, and at receivers in the footprint the phases of the signals received from the two satellites are compared. This phase difference is dependent upon receiver location, but by measuring phase difference no absolute timing or phase measurement is required. A common key is generated at the receivers in a certain area. The output of selected receivers is fed back to the broadcast control centre and is used to encode the location-based services for that area. Preferably the operation is conducted on multiple frequencies and in multiple rounds of such frequencies. A multibit keyword can be directly generated at the receivers by use of a discrete Fourier transform (DFT) and combining its outputs for different rounds.

Abstract: Video is encoded by applying a vertically and horizontally separable transform to provide a block of transform coefficients; and quantising the transform coefficients. Prior to quantisation, a filtering operation is performed on the block of transform coefficients, the filtering operation applying a rotation to pairs of coefficients in the block. Each pair of coefficients may be symmetrically positioned with respect to the leading diagonal of the block.

Abstract: A television receiver apparatus is described. The television receiver apparatus comprises an input interface arranged to receive commands from a user, a communication interface arranged to send and receive data over a one-to-one communication network, a broadcast receiver arranged to receive data sent over a broadcast network, a display interface arranged to connect to a display device, and a processor. The processor controls the display device to display an electronic programme guide comprising a schedule of programmes being broadcast and to be broadcast. The processor receives a selection of a programme displayed in the electronic programme guide and a command to find additional episodes of the programme, generates a list of additional episodes of the programme comprising at least one episode available on-demand via the communication interface, and controls the display device to display the list of additional episodes.

Abstract: A television receiver apparatus is described. The television receiver apparatus comprises an input interface arranged to receive commands from a user, a communication interface arranged to send and receive data over a one-to-one communication network, a broadcast receiver arranged to receive data sent over a broadcast network, a display interface arranged to connect to a display device, and a processor. The processor controls the display device to display an electronic programme guide comprising a schedule of programmes currently being broadcast, programmes to be broadcast after the current time, and programmes previously broadcast in a time period prior to the current time. The processor receives a request to view a selected programme displayed in the electronic programme guide, retrieves the selected programme from the communication network if the selected programme was previously broadcast in the time period, and controls the display device to display the selected programme.

Abstract: A graphical user interface for a computer program, the interface comprising an array of main panes each providing access to a particular aspect of the program, the panes being in register with one another at a vertex corresponding to the area in which all the panes meet, each of the panes being adapted to expand as a pointing device highlights a pane, the expansion of said pane relative to the other panes wherein the panes remain in register with one another at the vertex as a pane expands.

Abstract: Various embodiments include a system for providing users access to audio/visual content, the system comprising means for storing content, means for broadcasting content on a scheduled basis, means for downloading the stored content from the storage means, means for enabling a user to access the downloaded content only within a specified time period, means for streaming content off the storage means, and means for receiving the content broadcast on a scheduled basis.

Abstract: An on-channel repeater has a receiving antenna for receiving an RF signal and a transmitting antenna for transmitting on the same frequency as the input signal. An amplification path between the antennas provides substantially linear processing and includes a combiner, a decorrelating delay and a power amplifier. A filter estimator receives a reference signal and the combiner output and generates a plurality of control coefficients which are applied to an adaptive filter which filters the reference signal accordingly and applies its output to the combiner. The reference signal is derived not from the output of the decorrelating delay but rather from the output antenna after the power amplifier. Where there is an adjacent transmitter generating potentially interfering signals, the transmitter output is coupled to the same transmitter antenna.

Abstract: A method of providing a volumetric representation of a three dimensional object includes defining a plurality of voxels in a three dimensional space, categorizing voxels as foreground or background according to at least one silhouette image of the object, foreground voxels being assigned a first binary value, and background voxels being assigned a second binary value, and assigning to at least some voxels a value intermediate between the first and second binary values.

Abstract: A method of outputting media content is described. The media content is coded according to a predefined coding scheme to produce coded media content. Enhancement data, comprising information for selectively enhancing at least one portion of the media content, is also supplied. A corresponding method of providing media content is also described, including receiving enhancement data for selectively enhancing at least one portion of the media content and providing enhanced decoded media content for the at least one portion based on the enhancement data. By providing selective enhancements, e.g. of critical portions, a user experience can be improved without requiring a significant increase in bandwidth and enhancements may be delivered over a different channel to the basic data.

Abstract: Auxiliary digital data are inserted into a main digital data stream, to be subsequently coded to produce a coded data stream, by identifying a component of the main data stream that will make substantially no contribution to the coded data stream. It is into this component that data from the auxiliary data stream is inserted. The main digital data stream may comprise MPEG coded audio data, and the component (which represents unoccupied sub-bands or being at a level at or below a quantization noise floor) identified by estimating sub-bands that are unoccupied, or estimating quantization levels.

Abstract: The invention provides a method of providing a volumetric representation of a three-dimensional object. The method comprises several steps, including obtaining a line list of points of at least one set of lines having start and end points corresponding to intersection of the lines with object boundary positions and obtaining an approximate volumetric representation of the object. Then, a modified volumetric representation is produced by modifying the approximate volumetric representation based on the start and end points of the set of lines and the approximate volumetric representation. The resultant modified volumetric representation of the object is more accurate than the approximate volumetric representation of the object. Also, a resultant data set from the present invention that defines the volumetric representation of the object contains continuous data as to the shape of the object, rather than mere discrete data. Therefore, the resultant data set contains more realistic data defining the object.

Abstract: A method for generating subtitles for audiovisual material received and analyses a text file containing dialogue spoken in audiovisual material and provides a signal representative of the text. The text information and audio signal are aligned in time using time alignment speech recognition and the text and timing information are then output to a subtitle file. Colors can be assigned to different speakers or groups of speakers. Subtitles are derived by receiving and analyzing a text file containing dialogue spoken by considering each word in turn and the next information signal, assigning a score to each subtitle in a plurality of different possible subtitle formatting options which lead to that word. The steps are then repeated until all the words in the text information signal have been used and the subtitle formatting option which gives the best overall score is then derived.

Abstract: A watermarking system and method is proposed for still or moving pictures in which a watermark is embedded robustly and simply into DC-values, but without causing unacceptable visible picture degradation. The watermark is secure and can be readily detected, and the method can be used to convey additional data. Also disclosed is a method for watermarking a sequence of pictures in which the visibility of artifacts is reduced. The watermark may carry data and may be used to label a program.

Abstract: An MPEG2 decoded video signal is accompanied by a representation of the coding decisions to aid downstream re-encoding. The representation is an MPEG compliant bit modified to reduce the number of bits.

Abstract: A watermarketing system and method is proposed for still or moving pictures in which a watermark is embedded robustly and simply into DC-values, but without causing unacceptable visible picture degradation. The watermark is secure and can be readily detected, and the method can be used to convey additional data. Also disclosed is a method for watermarking a sequence of pictures in which the visibility of artifacts is reduced. The watermark may carry data and may be used to label a programme.

Abstract: In a system in which an auxiliary data signal is conveyed with a decoded audio signal to assist in re-encoding, signature information is provided to assist in detecting changes in the decoded audio signal which would render the auxiliary data signal of little or no use in re-encoding. The signature information is most preferably included in the auxiliary data signal.

Abstract: An RF active deflector is described for use with orthogonal frequency division multiplex signals. An input antenna receives an RF input signal and an output antenna transmits an RF signal on substantially the same frequency as the input signal. An amplification path between the input antenna and the output antenna provides substantially linear processing and includes a delay. Means responsive to the signal in the amplification path produce a plurality of control coefficients. A transversal filter receives the signal in the amplification path and, under control by the control coefficient, provides a modified signal. A combiner is provided for combining the modified signal with the signal in said amplification path so as to reduce the effect of the feedback.

Abstract: A method of providing a visual representation of a scene to a participant in a studio is provided, wherein the studio is arranged to be viewed by a camera to provide a camera image and has at least a portion of a background object arranged to be keyed out of the camera image by a keying process. The method includes obtaining an estimate of the viewpoint of the participant; rendering an image of the scene based on the viewpoint of the participant; and projecting at least a portion of the rendered image onto the background object to provide a projected image portion visible to the participant. The projected image portion is projected so as to be keyed out of the camera image by the keying process.

Abstract: An MPEG bitstream is switched in the video domain in between a decoder and recoder pair which remain continuously in operation but which are transparent through re-use in the recoder of coding decision taken in the upstream coding of the MPEG bitstream and inferred in the decoder of the switch. Around the switch point, the coding decisions are modified.

Abstract: A method and display are disclosed in which a representation of a 3D model is provided for presentation as a 3D image. The image may be presented under an array of spherical or lenticular microlenses so that different images are presented at different viewing angles. The images are rendered using a set of orthographic projections; this can avoid the need for multiple cameras or the highly computer intensive processing associated with generation of simulated camera images and can also give improved results as compared to prior art multiview images.