Abstract: An OFDM (orthogonal frequency division multiplexing) receiver that detects and corrects a sampling frequency offset of a sampled signal. The OFDM receiver samples an incoming signal in the time domain, multiplies the sampled data by a window function to widen the main lobe of each of the predetermined subcarriers' frequency domain spectrum, takes an FFT (fast Fourier transform) of the sampled signal to analyze the frequency domain samples of each predetermined subcarrier, detects a difference in magnitude of the frequency domain samples for each predetermined subcarrier, and generates a sampling frequency error based on the detected changes in magnitude.

Abstract: An image processor produces a DPCM prediction error to be quantized. If the prediction error value is positive, the value passes unchanged to a quantizer. If the prediction error value is negative, a bias value is added to the prediction error value to produce a positive number within the operating limits of the quantizer. Biased prediction error values are quantized. Because all values received by the quantizer are positive and within the current quantizer limits, the quantization table used by the quantizer need not include quantization values for negative prediction error values. This reduces the scope of prediction error values by a factor of two, doubling quantization resolution.

Abstract: A transcoding method for inserting a visual element into an encoded bit stream with minimal decoding of the encoded bit stream. The transcoding method includes the steps of receiving an encoded bit stream containing a picture, partially decoding a copy of the bit stream, determining if a segment of the picture in the bit stream is affected by the insertion of the visual element, re-encoding the segment if the segment is affected by the insertion of the visual element, and outputting the re-encoded bit stream. The encoded and re-encoded bit streams may be MPEG-encoded bit streams. The re-encoded bit stream may be output using a bit rate control process that randomly selects an initial processing point within the re-encoded bit stream, requantizes the re-encoded bit stream using a modified quantization table, and/or utilizes a slice-level stopping criteria for selectively starting or ending bit rate control.

Abstract: The agent for communication between a manager (20) and at least one resource (30) comprises a protocol core (111) created automatically from a formalized description of the resource (30), this core (111), once created, comprising in compiled form an interface (14) for communication with the manager (20) and a model (11) of the resource (30) comprising the values of the instances of the resource (30), these values being accessible by the administrator (20) through the communication interface (14).

Abstract: A system for receiving a plurality of broadcast channels transmitted with different polarizations includes a first demodulator for demodulating a first channel having a first polarization to produce a first demodulated channel signal, and a second demodulator for demodulating a second channel having a second polarization, opposite to the first polarization, to produce a second demodulated channel signal. An adaptive interference cancellation network, coupled to the first and second demodulators, cancels interference, derived from the second channel, in the first demodulated channel signal to produce a received signal.

Abstract: An MPEG decoder in a high definition television receiver decodes and decompresses MPEG coded data to produce decompressed image pixel blocks, and includes a motion compensation network coupled to a frame memory to produce finally decoded pixel data for display. The decompressed MPEG data is recompressed by plural parallel recompressors prior to storage in frame memory. Each recompressor receives a datastream of interleaved pixel data, and predicts and compresses interleaved pixel values during each clock cycle, respectively. One of the recompressors is de-energized in a reduced data processing mode when pixel data is subsampled prior to recompression. Subsampled data is re-ordered prior to recompression. Multiple parallel decompressors coupled to the frame memory provide pixel data to the motion processing network. A control unit, insures an uninterrupted interleaved data flow to the decompressors by repeating last valid data when source data is interrupted.

Abstract: A compressed audio/video, includes circuitry to measure the relative synchronization of decompressed audio and video signals. If audio and video signal synchronization is within a first range of values, synchronization circuitry within the receiver will attempt to appropriately time align the signals. Alternatively, if actual synchronization exceeds the first range, attempts to synchronize the signals are suspended and non-synchronized decompressed audio and video signals are provided.

Abstract: A video processing system adaptively generates and processes volume/file structure and navigation data of different data format in distinct modes including (a) pre-processing, (b) contemporaneous and (c) post-processing modes for decoding, recording and other applications. The system processes a video program comprising encoded digital packetized data representative of a sequence of individual images and ancillary file structure and navigation data supporting navigation through image sequences. The system parses the packetized data to determine characteristics of individual images prior to storage and uses the characteristics for generating navigation information. The generated navigation information includes a predetermined element constrained to a selected sub-set of elements to reduce subsequent processing. The system also generates a menu including an item enabling User selection and initiation of a function associated with the video program using the generated navigation information.

Abstract: A dynamically configurable video signal processing system including an encoder and decoder processes data in the form of hierarchical layers. The system partitions data between hierarchical layers and allows variation in the number of layers employed. Data is automatically partitioned into one or more hierarchical layers as a function of one or more parameters selected from available system bandwidth, input data rate, and output signal quality. In addition, the image resolution and corresponding number of pixels per image of the data may be varied as a function of system parameters.

Abstract: Interface apparatus for interfacing data to a plurality of different clock domains where the clock signals in the different domains are phase locked together and respective clock signals have different frequencies includes a plurality of cascade connected first and second latches coupled between respective clock domains. One of the latches is a clocked Data Latch and the other is a clocked and Enabled Data Latch. A timing generator provides respective domain clock signals, wherein a domain clock signal of a domain providing a data signal is applied to the clock input connection of the first latch of a respective cascade connected set of latches and a domain clock signal of a domain receiving said data signal is applied to the second latch. The timing generator also provides a common Enable Signal phase locked to the domain clocked signals. The common Enable Signal is applied to the enable input terminal of one of the latches of each set of cascade connected latches.

Abstract: An exemplary video encoder is provided that quantizes pel blocks of a video signal based upon one or more of the following: (i) an actual bit distribution of a previously encoded video frame, (ii) a required decoding delay for a splice point, and (iii) an activity measure of a pel block being encoded. Moreover, an exemplary video encoder uses the above quantization techniques to obtain an encoded video stream having seamless in points and seamless out points. Video encoding methods that utilize the above quantization methods are also provided.

Abstract: An exemplary video encoder is provided that quantizes pel blocks of a video signal based upon one or more of the following: (i) an actual bit distribution of a previously encoded video frame, (ii) a required decoding delay for a splice point, and (iii) an activity measure of a pel block being encoded. Moreover, an exemplary video encoder uses the above quantization techniques to obtain an encoded video stream having seamless in points and seamless out points. Video encoding methods that utilize the above quantization methods are also provided.

Abstract: For broadcasting purposes a multi-channel audio encoder board has been designed. Input time stamps are generated which become linked at least in one input processing stage with frames of said audio data to be encoded, wherein the input time stamps or time stamps derived from the input time stamps remain linked with the correspondingly processed frame data in the different processing stages in the processing, but are at least in the last processing stage replaced by output time stamps. In each of theses stages the corresponding time stamp information linked with current frame data to be processed is regarded in order to control the overall delay of the processing.

Abstract: The invention concerns a method comprising a step which consists in a quantizing step relative to a pixel or group of pixels in accordance with a desired rate. The invention is characterized in that it comprises an additional step which consists in modifying the quantizing step on the basis of an information of a subjective nature concerning said pixel or group of pixels. The invention is applicable to compression of video images.

Abstract: The present invention is a button on a device that has the ability to detect when a finger touches or is proximate to the button, especially to cause the initiation of a particular feature/function of the device. The button includes a proximity detector that is operable to sense or detect when a user's finger is proximate or on the button. The proximity detector may take many forms. These forms may be combined to provide greater selectivity. Additionally, sensitivity of the proximity detector may be set via threshold values. Sensitivity of the proximity detector correlates to detection or sensing of a user's finger at various distances from the button. One application is as an autofocus/shutter button on a camera.

Abstract: An MPEG coded and compressed video signal is received and decompressed for display. Prior to storing frames required for motion compensation in memory, pixel blocks are recompressed into DPCM prediction error values to reduce bandwidth and frame memory requirements. Fixed length quantization and dequantization tables (FIG. 2) have N levels (e.g., 15 levels), and each level has an associated output symbol of predominantly M bits (e.g., 4 bits), except that at least one of said N levels (e.g., level 7) is defined by a unique short symbol having less than M bits (e.g., 3 bits), and input data for that level is received at a desired rate. Each time a short symbol is used to represent a data value, bandwidth and memory are reduced and/or preserved for other uses, for example, inserting overhead data into a fixed-size data stream. For large sequences of data, such as exists for video data for example, the reduction in memory and bandwidth is significant.

Abstract: In analogue television systems, it is known to compensate for the receiver-end luminance defects which are caused by transmitter-end low-pass filtering of the gamma-predistorted chrominance signals, with the aid of transmitter-end correction signals. This method for luminance correction can also be used in connection with modern picture coding methods such as e.g. MPEG. To that end, the chrominance is encoded and decoded again in the encoder. A correction signal is derived from the decoded chrominance signal and is used during the encoding of the luminance. The macroblocks which are motion-compensated for prediction are based on the correspondingly decoded chrominance signal and on the decoded, corrected luminance signal.

Abstract: For broadcasting purposes a multi-channel audio encoder board has been designed. A requirement for such encoders is that they are able to operate with different encoding parameters. It may happen that encoding parameters change during encoding operation. In order to avoid the output of invalid data the encoding parameters required for a specific processing path are added to the input streams for the audio channels and become linked with the associated audio data and are stored in various buffers together with its audio data, i.e. the corresponding encoding parameters are kept linked with the audio data to be encoded throughout the encoding processing.

Abstract: The invention relates to a method of image compression, especially of the MPEG2 type, in which the images are coded according to groups (GOPs) each of which comprises N images, with an I image coded in intra mode, P images predicted as a function of the intra image I or of the preceding P image, each P image being preceded and followed by n bidirectionally predicted B images, n possibly being zero. The number M=n+1 represents the structure of the group. At least one parameter characterizing the source images which are to be coded according to a group is determined using a test coding (70), and the numbers N and M are made to depend on this parameter or these parameters. In the course of the test coding, defined values are conferred on N, M, and on the quantisation interval Q.

Abstract: An exemplary video encoder is disclosed that quantizes pel blocks of a video signal based upon one or more of the following: (i) an actual bit distribution of a previously encoded video frame, (ii) a required decoding delay for a splice point, and (iii) an activity measure of a pel block being encoded. Moreover, an exemplary video encoder uses the above quantization techniques to obtain an encoded video stream having seamless in points and seamless out points. Video encoding methods that utilize the above quantization methods are also disclosed.