Abstract: A high-penetration transmission method uses a compact character set for encoding an alphanumeric message, in which the signal margin is increased by a combination of bit repetition and a relatively small increase in power. The combination of bit repetition and a relatively small increase in power with a encoding via a compact character set avoids unacceptable delay characteristics. Moreover, the combination of repetition and a relatively small increase in power with the compact character set of the present invention avoids the co-channel interference problems of systems which rely solely on a power increase to increase the signal margin, as less power increase is required to obtain the same increase in signal margin for a given delay time. In one embodiment, a mobile radiocommunication system is provided with a short message service feature for transmitting alphanumeric messages to and from a mobile unit.

Abstract: A method and apparatus are provided for communicating information. This may include comparing a current item list with a reference item list and determining a type of classification based on the comparison. That is, the comparison may determine a difference between the current item list and the reference item list. Information regarding this difference may be sent from a first entity to a second entity.

Abstract: A highly-efficient system and methodology for organizing, storing and/or transmitting compressed data that achieves optimum compression throughput, enhances overall data compressibility, and reduces decompression latency.

Abstract: Output symbols are generated using input symbols and basis elements. A plurality of basis elements are generated. Each basis element is generated from a predetermined function of associated input symbols associated with the basis element. For each output symbol, a set of associated basis elements associated with the output symbol is determined, and a set of direct associated input symbols directly associated with the output symbol is determined. For each output symbol, the output symbol is generated from a predetermined function of the associated basis elements and the associated input symbols.

Abstract: A system and method for generating a transport packet stream having an output formatted as an ASI group having a plurality of short and long ASI packets in a fixed sequence. The short and long ASI packet each have an associated transport packet and a fixed number of special idle characters and the transport packets are dispersed among the special idle characters.

Abstract: A method and apparatus are provided for compressing data. The method includes the steps of determining a flux, scaling factor and sign of a difference between a new sample and a previous sample and encoding the difference of the new sample over the previous sample based upon the determined flux, scaling factor and sign of the new sample.

Abstract: A system and method employing an improved data compression and decompression technique for use in a communication system Specifically, the system and method employs an improved YK algorithm which uses an appropriate form of the trie data structure for the parsing operation. With the use of this data structure, the parsing complexity using this data structure is essentially proportional to the data size, and hence is very fast. The improved YK algorithm also is capable of handling errors in data without getting into an ambiguous state or causing the hardware or software system to crash. Furthermore, the improved YK algorithm is also capable of parsing the data based on predefined frequency characteristics and predefined grammar. The improved YK algorithm also sequentially updates the grammar, while keeping the number of variables below a pre-defined limit. This changes the grammar gradually, and can potentially increase the compression efficiency.

Abstract: The present invention employs an extra array of character history matching storage flip flops wherein the extra set operates in an alternating sequence with the first set depending upon the occurrence of a character mismatch, to ensure that every character received by a data compressing system is treated and considered in the same clock cycle in which it is received. The resultant circuit and method provides a much more speedy and efficient method for compressing data and for preprocessing of data which is to be compressed.

Abstract: The bits comprising a computer data structure are reversed rapidly and efficiently using a combination of data partitioning and table look ups. In an exemplary embodiment, the invention is employed in the pre-processing of Advanced Configuration and Power Interface (ACPI) tables stored in little-endian format for use by a big-endian operating system.

Abstract: A method and apparatus for compressing packets that enables inter-packet compression thereby achieving greater robustness and increased compression ratios without the deleterious effects, e.g., the effect of packet loss multiplying, of prior compression schemes. More particularly, a so-called acknowledgment scheme is employed in conjunction with the specific compression algorithm such that the transmitter, i.e., sender, can limit the history used by the compression algorithm to those packets that are correctly received. In particular, a vector identifying the packets used as the history is included in the compressed packet thereby enabling the receiver to reconstruct the packet history state necessary to decompress the packet. Advantageously, increased robustness and greater compression ratios are achieved independent of any particular one compression scheme.

Abstract: A method for reducing radio frequency interference from a high frequency serial bus by scrambling data signals and reducing the repetition of control signals. Beginning and ending control signals are provided with meaningless signals provided therebetween.

Abstract: A method and computer program product are provided for implementing text conversion table compression. For implementing text conversion table compression, a character sequence is loaded from a full-size conversion table. The character sequence is checked for one of plurality of character patterns. Responsive to identifying one of the plurality of character patterns, the character sequence is compressed into a compressed conversion table for the identified one character pattern. Responsive to failing to identify one of the plurality of character patterns, the character sequence is copied into the compressed conversion table. The character sequence from the full-size conversion table is checked for one of the plurality of character patterns including a repeating character sequence, a ramping character sequence, and a repeating high byte character sequence.

Abstract: A device and method for utilizing a single clock signal to generate a digital data stream signal for transmission in a compressed domain transmission system. The device includes a plurality of packetized elementary stream encoders electronically coupled to a transport stream encoder electronically coupled to an output interface adapted to generate the digital data stream signal.

Abstract: A lossless encoding methodology is described based on residual coding techniques and using a modified Least Mean Squares methodology to develop a predictor for a signal to be encoded, and a residual as the difference between the signal and its predicted value. After the residual for an input signal segment is obtained according to the method of the invention, that method is again applied to the residual value process to develop a second predictor, from which a second residual value is obtained. The method is then applied for at least one further iteration to the most recently obtained residual value process to develop a third predictor for the signal to be encoded. A single prediction value is then selected as a statistical representative of those multiple predictor values. The residual value to be used for encoding the input signal increment is determined as the difference between the signal value and the selected predictor value.

Abstract: Logic circuitry performs a matching algorithm function. A memory produces a match signal that indicates which memory cells contain data that matches input address data to the memory. A first logic AND function performs a logic AND between a current value of the match signal currently produced by the memory for the input address data with a prior value of the match signal produced by an immediately prior input address data. A buffer holds index data. A second logic AND function compares output of the first logic AND function with the index data. Output of the second logic AND function is returned to the buffer as new index data. Index logic generates an offset based on the index data stored in the buffer. A send byte function asserts a send byte signal when the match signal is zero and when the output of the second logic AND function is zero. A length counter is incremented for every cycle in which the send byte signal is not asserted.

Abstract: The invention is a method of relocating of header compression/decompression functions between a plurality of network entities and mobile compressors and/or mobile decompressors.

Abstract: The invention is a method of relocating of header compression/decompression functions between a plurality of network entities and mobile compressors and/or mobile decompressors.

Abstract: Encoding and decoding systems and methods for digital data in 24 bit sequences. An encoder generates state variables as a function of four or fewer bits of the 24 bit sequence, and encodes the sequence into 11 and 14 bit codewords. After transmission, the 11 bit and 14 bit codewords are decoded using recovered state variables. The encoding places a run length limit (RLL) of k=7 on a 25 bit codeword comprised of the 11 and 14 bit codewords to limit runs of zeros. Each of the 11 bit and 14 bit codewords are preferably also encoded with a run length limit of interleaved bits is i=7. The encoding and decoding systems and methods can be applied to a magnetic disc drive.

Abstract: A data conversion apparatus for converting first data into second data. An input section receives the first data. A conversion section converts the first data into the second data by moving each of the first data to the position of second positional information that is represented by a sequence of numbers that is obtained by reversing the order of a sequence of numbers of first positional information that is an N-ary number (N: a natural number that is greater than or equal to 2) and represents the position of each of the first data. The data conversion apparatus can easily distribute data existing in a temporally or spatially localized region.

Abstract: This invention relates to data input/output apparatus and the like, which are suitable to be applied to an AV server. As nonlinear accessible storage medium, there is provided with HDD array device (13). When a controller (11) of an AV server (10) receives a command for reproducing data from a minimum of two discontinuous areas in the HDD array device (13) in a first order, the HDD array device (13) then puts the command in an order such that a period of time for access is minimal to reads the data so that the read data are rearranged in the first order to be outputted through decoders (15) to (18). Thereby, the efficiency of data transfer is improved without complications.

Abstract: A method and apparatus for compressing packets that enables inter-packet compression thereby achieving greater robustness and increased compression ratios. More particularly, a variable-length coding is used in conjunction with maintaining a separate hash table for each packet. Further, the per-packet hash table indexes particular byte strings in the packet but does not index data in any other packet(s). That is, a respective separate hash table for each packet is employed wherein such hash table is constructed as the particular packet is compressed. As such, the respective hash table is encoded with the particular packet. Employing a per-packet hash table in combination with variable history state inter-packet compression provides for efficient and robust overall compression of the packets.

Abstract: A method comprising entropy encoding into bits a set of data values, and packing into storage the entropy encoded bits by reversing the bits of words with unknown length and keeping in blocks the words with known lengths. For instance, in an entropy encoded data set that uses both Huffman coding and zero run coding, the class code may be reversed in bit order from right to left rather left to right while the words of known length such as the zero run code and Huffman pointer are stored left to right in blocks. This data arrangement is particularly useful in an MMX based machine.

Abstract: A system for storing and replaying packet information involves storing at least a portion of a header in a different memory location than the sample data. A linked list may be developed to link the headers and to link the headers to the sample data. After replaying the stored information a predetermined time or times, the header may be destroyed, thereby preventing the replay of the received information.

Abstract: A method of converting a plurality of strings stored in an input buffer to a plurality of evenly spaced strings in an output buffer involves first passing over the input buffer and, for each string, placing the string in the output buffer at a next available address. If the string length is longer than a maximum string length, the maximum string length is set to the string length and the string is set as the last incorrectly placed string in the output buffer. The next available address in the output buffer is incremented by the maximum string length plus the product of any positive difference between the current string length and previous maximum string length and the number of strings already placed in the output buffer. A second pass over said output buffer from the last incorrectly placed string in a direction opposite the first passing step moves each string within the output buffer to an address being a multiple of the maximum string length from the start of the output buffer.

Abstract: An adaptive linear predictor is used to predict samples, and residuals from such predictions are encoded using Golomb-Rice encoding. Linear prediction of samples of a signal which represents digitized sound tends to produce relatively low residuals and those residuals tend to be distributed exponentially. Accordingly, linear prediction combined with Golomb-Rice encoding produces particularly good compression rates with very efficient and simple implementation. A code length used in Golomb-Rice, which is typically referred to as the parameter k, is adapted for each sample in a predictable and repeatable manner to further reduce the size of a Golomb-Rice encoding for each sample. An infinite incident response filter of processed residuals automatically reduces influences of previously processed residuals upon such adaptation as additional samples are processed. The efficiency of Golomb-Rice encoding is improved by limiting the predicted samples to an efficient range.

Abstract: A method of mapping a substring of a bit stream to a symbol selected from a set of symbols, comprising: determining if the numeric value of an n bit substring of the bit stream is below a threshold; selecting the symbol from a first subset of symbols if the numeric value is below the threshold; selecting the symbol from a second subset if the numeric value is equal to or greater than the threshold and the next bit of the bit stream is a 0; and, selecting the symbol from a third subset if the numeric value is equal to or greater than the threshold and the next bit of the bit stream is a 1.

Abstract: An apparatus for transmitting a digital information signal includes an input terminal for receiving the digital information signal, a first channel encoding unit for carrying out a first channel encoding step on an information word in a series of subsequent information words included in the digital information signal so as to obtain a channel word, a compression unit for carrying out a compression step on a channel word so as to obtain a compressed channel word, an error correction encoding unit for carrying out an error correction encoding of the compressed channel word so as to obtain a parity word, a second channel encoding unit for carrying out a second channel encoding step on the parity word so as to obtain a channel encoded parity word, and a formatting unit for combining the channel word and the channel encoded parity word into a composite transmission signal suitable for transmission via a transmission medium.

Abstract: It is intended to provide a buffer control method which performs control by deciding if data should be held in buffer, thereby enabling to reuse the data stored in the buffer. This method has the following steps of: storing data in a buffer; receiving, as an input, expiration time information indicating a time to stop holding the data; comparing time clock information indicating a time clock of a decoding apparatus with the expiration time information; and controlling the holding of the data within the buffer according to the comparison.

Abstract: There is provided a high speed variable length coding system having a small hardware scale.

Abstract: A bit stream parsing apparatus for an audio decoder includes a register unit for storing therein predetermined bits of data stream, a normalizing barrel shifter for shifting the data stream stored in the register unit by a predetermined number of bits, a mask gate unit for masking the number of bits which are to be sampled among the data outputted from the normalizing barrel shifter, and an accumulator for accumulating an output value of the mask gate unit. The apparatus employs a load and parallel shift technique and enables an N-bit stream to be sampled in a single clock cycle, thereby accomplishing a speedy operation.

Abstract: A digital communication system communicates data between a transmitter station and a receiver station by means of a carrier wave. The transmitter station has a packet assembler for assembling data having an original format into a packet, an encoder for encoding the data in the packet from an initial eight-bit form into a fourteen-bit form, and a modulator for modulating a carrier wave by the encoded data so as to transmit the packet of encoded data in the fourteen-bit form. The receiver station has a demodulator receptive of the modulated carrier wave for demodulating the same to separate therefrom the packet of encoded data, a decoder for decoding the encoded data in the packet from the fourteen-bit form into the initial eight-bit form, and a packet disassembler for disassembling the packet of decoded data to restore the original format of the data having the initial eight-bit form.

Abstract: Extended lossless imaging method and system, useful for medical and other imaging, where a succession of values of optical density or other feature of interest may be obtained by scanning an image as an array, or may be selected otherwise. Image data values in binary form are linked end to end into a concatenated number, partitionable into a set of ordered (non-repeating) numerical terms summing to it. Position counts of such a concatenated number also may be summed, as to give a "characteristic" whole part of a real number, and may be encoded arithmetically to give a "mantissa" fractional part thereof. The derived numbers are electronically stored for retrieval directly or by reverse computation, to yield reconstituted image data values, from which a lossless replica of the original image is readily made.

Abstract: A buffer memory controller allows to sequentially store sampled data having variable bit length. That is, rather than assigning each sampled data to a single word of the memory, the sampled data is sequentially stored head to tail so that memory space is not wasted.

Abstract: A method, system, and apparatus for performing encoding employing a pseudo-barrel shifting technique. An encoder is provided with a buffer of at least twice a maximum symbol size. The encoder enables a window of bits in the buffer to be written during any time period. A steering circuit in the encoder steers valid data bits of an incoming symbol into appropriate enabled bit locations in the buffer. A read-out circuit in the encoder reads a data block of the maximum symbol size from the buffer after a write causes a boundary crossing in the buffer.

Abstract: A method and an apparatus for processing a plurality of operands in parallel including packing the operands into a word with at least one cleared buffer bit between each operand and processing the packed word.

Abstract: An applications programming interface 20 to a telecommunications management network includes a command language interpreter 24 and a compiler 40. A command string input/output format is provided, the command strings 42 including network management parameters. The interpreter includes interpreter scripts for converting the network management parameters between the command string format and a network management protocol compatible format. The compiler compiles interpreter scripts for encoding and decoding user defined parameter types, which are then loaded dynamically to the interpreter. The interface provides a convenient "command line" API, while at the same time permitting extensions to the interpreter in a dynamic manner.

Abstract: An audio signal encoder is provided which is designed to A/D-convert an analog input signal at a first sampling frequency without being compressed and at a second sampling frequency that is two or four times higher than the first sampling frequency in data compression for minimizing data compression-caused errors in high-frequency components encoded. A decoder decoding digital signals produced by the encoder and a record carrier storing therein the digital signals are also provided.

Abstract: A method and apparatus are provided for receiving a packet stream having fixed length packets. Data carried in the packet stream is selectively processed for output to a computer. A packet identifier filter selects particular packets from the recovered packet stream. A computer disk controller receives the packets selected by the filter and manages the transfer of packet data from the packets to and from a buffer. A data bus is coupled to the disk controller for communicating the packet data from the buffer to the computer. A data compression stage prior to the disk controller compresses packets from the recovered packet stream in order to provide a gap between data carried by successive packets to be provided by the disk controller. In this manner, a low cost disk controller chip can be used to control the buffering of data in a cable or satellite television modem that provides, e.g., Internet access.

Abstract: A variable bit-length code processing circuit includes first, second and third registers (12, 20, 22) each of which is of 1 word, and memory data is loaded to the first register (12), and a variable bit-length code is withdrawn from the third register (22). The second register (20) and third register (22) are coupled to a barrel shifter (16) which barrel-shifts data of 2 words according to a barrel shift amount which is applied by a subtracter (30) on the basis of the number of the valid bits and the number of the remaining bits.

Abstract: In a video system having an encoder and multiple decoders, a snooping circuit in each decoder compares an address on a common data bus to determine whether encoded video data is read or written by a host computer. When the address on the common data bus is detected to be an address within a predetermined range, the read or write data on the common data bus is latched into a first-in-first-out (FIFO) memory. A decoding circuit in each decoder decodes from the FIFO memory to provide a decoded video data output stream. In this manner, multiple decoders can be supported by the video system without additional bandwidth demand on the host computer.

Abstract: An apparatus and method for parallel data compression and decompression uses packing and unpacking of data which has multi-variable components, for example, relational multi-variable content data such as tristimulus color space data used in color hard copy applications. Multiple input words are compressed in parallel compression engines and fed in parallel to a packer device which configures the codes in an order determined by order of compression and byte count for each word into a single bit string code. In the decompression cycle of the process, an unpacker device separates the single bit string code based upon length of a data string represented by a code word last decoded by either the decompression engine for that code word if the decompression engine is idle, or the length of the string that has been decoded so far if the decompression engine is currently working on a code.

Abstract: An apparatus for encoding variable length codes (VLCs) represented by variable-length codewords and their lengths, and segmenting variable-length codewords of the VLCs into fixed-length segments for a transmission thereof, comprises: a lookup table for mapping each of source codes into each of the VLCs to produce each of the variable-length codewords and its length; a first barrel shifter, in response to the length of the present input variable-length codeword, for concatenating a present input variable-length codeword and a concatenated variable-length codeword together; a second barrel shifter, in response to a control signal, for producing a fixed-length segment out of combined inputs of the present input variable-length codeword and the concatenated variable-length codeword; an adder for adding the length of the present input variable-length codeword and an added length to produce a newly added length; and a register for comparing the newly added length with a predetermined number of bits to store the new

Abstract: A coding scheme for transmitting messages particularly between computers is described. Messages are transmitted in packets which include at least a data portion and a terminator. Out of a predetermined set of symbols, sixteen data symbols and at least one control symbol is selected. The terminator token is generated to constitute the symbol and a six-bit symbol representing checking bits.

Abstract: An efficient packed encoding rules (EPER) for ASN.1 for efficiently encoding the value to each type of abstract syntax definition, in which structure of an encoding data is divided into three fields of a bit field, an octet field following the bit field, and an offset field selectively added to before the bit field, in the bit field, bit data is set in the order of the abstract syntax definition, in the octet field, octet data in a unit of octet is set in the order of the abstract syntax definition, in the offset field, a length information of bit field is set and, in the bit field, padding is made so that a total length of the offset field and the bit field is an integer multiple of 8 bits, and the offset field is added when the length of bit field is not determined from the abstract syntax definition, thereby eliminating problems of PER.

Abstract: A lossless data compression system and method compresses a set of M data words stored in a computer memory. A first table stores data representing last occurrence positions among those of the M data words already processed for all distinct word values. A second table stores for each data word an entry indicating the position, if any, of a most recent prior occurrence of another data word with the same word value. A dictionary index indicates how many distinct data word values have been encountered during processing of M data words.

Abstract: A method and apparatus for compressing a data vector of a predetermined number of data points. The apparatus includes a memory for storing the compressed data vector, a first comparator for determining a largest and smallest data point of the data vector and a second comparator for comparing the largest and smallest data point and when they are equal, causing a first data point of the data vector to be stored in the memory as the compressed data vector. The apparatus also includes a first processor for determining a data field width necessary to uniquely describe a largest relative magnitude data point and a second processor for storing the data points of the data vector as the compressed vector in data fields of memory of the data field width.

Abstract: A high-speed out-of-band signalling technique for transferring information such as station status information between stations in a communication network, typically a local-area network, involves sequentially generating a plurality of n-bit sequence segments, where n is at least 3. Each bit is either a first binary value or a second binary value. Each sequence segment is coded with one of a plurality of different n-bit code groups divided into a first code group and a set of second code groups. The n bits in the first code group are all the first binary value--e.g., all "1s". None of the second code groups contain a pair of non-contiguous bits of the second binary value--e.g., none of the second code groups contains two "0s" separated by at least one other bit. The sequence segments are outputted in the order that they were generated to produce a special bit sequence which carries the desired information.

Abstract: A method for transmitting pieces of synchronized picture data having the same data length of which each include a synchronizing signal, an identifying code, pieces of compressed picture data having different data lengths and an error correcting code in that order is disclosed. To correctly decode each of the compressed picture data, it is required to start a decoding operation from a head address of each of the compressed picture signal. Therefore, in cases where a head address of a piece of compressed picture data exists in a piece of synchronized picture data, an existence information flag for informing the existence of the head address, an address pointer for indicating an address of the head address, and a block number for indicating a position of the compressed picture data having the head address are added just after the identifying code to correctly decode the compressed picture data and other pieces of following compressed picture data in the synchronized picture data.

Abstract: A variable length codeword packer communicates codeword data in successive m-bit bytes. A binary sum is accumulated indicative of a total number of codeword bits received over time. A byte pointer is derived from at least one most significant bit of the binary sum. A bit pointer is derived from a plurality of least significant bits of the binary sum. A first data storage array has a plurality of m-bit first storage bytes and is responsive to the byte pointer for storing received codeword data in the first storage bytes. A second data storage array has a plurality of m-bit second storage bytes and is responsive to the byte and bit pointers for filling the second storage bytes with codeword data from the first data storage array. m-bit bytes of codeword data are output from each filled second storage byte to provide successive m-bit bytes of codeword data. The use of a multistage approach in packing variable length codewords substantially reduces the complexity as compared to single stage designs.

Abstract: A structure and a method capable of both packing data into and unpacking data from either the little endian or the big endian format are provided. Under the structure and method of the present invention, the packed or unpacked data, as the case may be, is only shifted in one direction. During a packing operation, a stream of n-bit data is packed into a stream of m-bit words. During an unpacking operation, a stream of m-bit packed data is unpacked into a stream of n-bit words. n.ltoreq.m.