Abstract: A bit clock recovery apparatus for digital storage readout employing sync frames, where an oversampled readout signal is stored in memory, sync patterns are located in the signal using DSP means, distances of consecutive sync pattern locations are calculated, and bit clock is recovered from these distances and the knowledge about the data framing structure.

Abstract: A wireless extension of the IEEE 1394 bus where two clusters of 1394 devices are linked by a wireless bridge. The device clusters communicate without being bridge-aware. The wireless bridge provides for a bus reset isolation. The wireless extension including a buffer memory for storing self-identification packets in the 1394 interfaces of both boxes of the wireless bridge. With these buffer memories the self-identification packets of the bus stations in the other cluster can be collected and they can be read out during the self-configuration phase of the network after a bus reset when the bus grant is assigned to the box of the wireless bridge that is also connected to the bus where the bus reset has occurred. The physical layer block of the 1394 interface transmits artificial self-identification packets for all bus stations of the other cluster.

Abstract: Today the storage of audiovisual (AV) data on storage media employs standardized coding schemes, e.g. MPEG-2. End user devices for AV presentation, like disc players, contain dedicated decoders implemented in hardware, which are able to decode data streams complying with the respective standard. The efficiency of this decoding methodology relies on the standardization of appropriate coding schemes. Proprietary coding schemes may be more efficient by being adapted to the content, or may be used for content protection or optional features. Using reconfigurable decoder hardware, storing the configuration data for the actual decoder on the same storage medium as the AV data, and downloading the data to configure the player can be used to implement proprietary coding schemes. Such schemes require appropriate player hardware, suitable to execute a downloaded decoder under real-time conditions, and a standardized format to store the decoder configuration data.

Abstract: A bit clock recovery apparatus for digital storage readout employing sync frames, where an oversampled readout signal is stored in memory, sync patterns are located in the signal using DSP means, distances of consecutive sync pattern locations are calculated, and bit clock is recovered from these distances and the knowledge about the data framing structure.

Abstract: Today the storage of audiovisual (AV) data on storage media employs standardized coding schemes, e.g. MPEG-2. End user devices for AV presentation, like disc players, contain dedicated decoders implemented in hardware, which are able to decode data streams complying with the respective standard. The efficiency of this decoding methodology relies on the standardization of appropriate coding schemes. Proprietary coding schemes may be more efficient by being adapted to the content, or may be used for content protection or optional features. Using reconfigurable decoder hardware, storing the configuration data for the actual decoder on the same storage medium as the AV data, and downloading the data to configure the player can be used to implement proprietary coding schemes. Such schemes require appropriate player hardware, suitable to execute a downloaded decoder under real-time conditions, and a standardized format to store the decoder configuration data.

Abstract: An electrical insulation device for bidirectional connecting lines is proposed which operates reliably at high frequencies and can be integrated easily on a chip. In accordance with a first embodiment, for the purpose of electrical isolation, two separate optocouplers are provided per bidirectional connecting line. A control unit evaluates the control signals which are output by one of the two circuit units, and thereupon activates one of the two optocouplers while the other optocoupler is simultaneously deactivated, in order, in this way, to allow transmission of signals via the associated connecting line in one direction. In a second embodiment of the invention, only a single optocoupler is provided per bidirectional connecting line.

Abstract: The invention deals with a wireless extension of the IEEE 1394 bus. Considered is a scenario where two clusters of 1394 devices are linked to each other by means of a wireless bridge (9). The devices of one cluster shall communicate with devices of the other cluster without being bridge-aware. The wireless bridge, however, provides for a bus reset isolation. This causes a problem each time a bus reset occurs in one of the clusters. To solve this problem it is proposed to implement a buffer memory (22) for self-identification packets in the 1394 interfaces (11) of both boxes of said wireless bridge (9). In particular these buffer memories (22) shall be implemented in the physical layer section (21) of the 1394 interfaces (11).

Abstract: The output bitrate of an MPEG-2 video encoder depends on the source data rate, the content or detail or degree of motion in the source pictures, the prediction type and on quantiser settings. The control of the encoder output bitrate is based on the filling level of a buffer containing VLC words. Corresponding to the actual filling level of this VLC buffer the quantiser settings are adapted in order to achieve a constant-bitrate encoder output. DVD-RAM devices are now on the market that are capable of storing such MPEG-2 video encoded video sequences. The bitrate control algorithm used has a severe impact on the achievable visual picture quality of the encoded video sequence. Therefore the current filling levels of two further buffers in the processing chain are additionally taken into account for the bitrate control: for the application with DVD-RAM, the mechanical buffer of a DVD recorder and the therein loaded DVD-RAM disc itself.

Abstract: Proposed systems for encryption and copy protection of digital video or audio data use known data stream encryption algorithms and require a significant amount of additional hardware for the encryption and decryption of the video and audio data. MPEG-2 video uses VLC code tables to generate the encoded data. The receiver has to know about the code tables that have been applied at the encoder in order to be able to decode the VLC-encoded data stream. As long as the encoder VLC code tables are not known the transmitted data cannot be decoded. Therefore the use of any non-standardized non-public VLC code tables when encoding the VLC words is a powerful protection for such MPEG-2 video data. According to the invention several different VLC code tables or several different sets of VLC code tables are used in the encoder and decoder. At regular or irregular time instants a different VLC code table or set of VLC code tables is selected synchronously in the encoder and decoder.

Abstract: A block of picture elements is DCT transformed and coded to produce a corresponding data block of variable length codewords having an average length. The data blocks are apportioned among fixed length transport blocks as needed to produce full transport blocks. The transport blocks include a direct (DC) component and alternating components at prescribed locations, as well as an address information flag indicating whether or not block data is longer or shorter than the average length, and an address pointer, to facilitate recovery and synchronization of apportioned data blocks at a decoder.

Abstract: A method and apparatus for the improvement of the resolution of digital signals. In digital TV signals which are transformed into a frequency domain, irregularities in the pattern of the reproduced video signals occur because of rounding off errors, when the number of bits per sample is reduced during calculation of the coefficients. This is remedied by increasing the coefficients of the transformed signal values following at least one first coefficient, for example a DC-coefficient, and reducing them again after inverse transformation. This is applicable to digital systems using block processing in which, because of a limited amount of bits, a rounding off of the transmitted spectral coefficients is performed in the calculation.

Abstract: A method and apparatus for the improvement of the resolution of digital signals. In digital TV signals which are transformed into a selected frequency range, irregularities in the pattern of the reproduced video signals occur because of rounding off errors, when the number of places is reduced during calculation of the coefficients. This is remedied by increasing the coefficients of the transformed signal values following at least one first coefficient, for example a uniform component, and reducing them again before inverse transformation. This invention can be employed in digital systems using block processing in which, because of a limited number of bits, a rounding off of the transmitted spectral coefficients is performed in the calculation.

Abstract: A television camera includes an acceleration correction device for correcting for sudden movements of the camera, to prevent blurring of the resulting television picture. The correction device changes the starting point on an image target depending upon the amount and direction of the acceleration. This correction does not occur until the acceleration exceeds a threshold value.

Abstract: A circuit for the transformation of digital video signals, which circuit includes components operative for effecting transformation of a digital video signal in the form of a matrix of signal elements in a sequence which processes the matrix signal elements row by row and column by column, respectively.

Abstract: Pile fabrics with a pile containing thermoplastic fibres are thermoprinted with a pattern, the contact pressure between the pile fabric and the thermoprinting web in the heating zone being such that about 40 to 60% of the pile is compressed, and immediately afterwards relief-formed and/or surface formed while still hot with a pattern which bears a strict relationship to the thermoprinted pattern. A machine for carrying out this process comprises a thermoprinting unit with adjustable contact pressure and a relief-forming and/or surface forming patterning unit which functions in synchronism and coordination therewith.

Abstract: Pile fabrics with a pile containing thermoplastic fibers are thermoprinted with a pattern, the contact pressure between the pile fabric and the thermoprinting web in the heating zone being such that about 40 to 60% of the pile is compressed, and immediately afterwards relief-formed and/or surface formed while still hot with a pattern which bears a strict relationship to the thermoprinted pattern. A machine for carrying out this process comprises a thermoprinting unit with adjustable contact pressure and a relief-forming and/or surface forming patterning unit which functions in synchronism and coordination therewith.