Abstract: There is disclosed a recording method for performing a DSV control while recording a recording signal generated by inserting a synchronous signal for decoding reproduction data into every predetermined number of code words in a code word string satisfying a predetermined run length restriction rule and to be outputted into a recording medium, when a plurality of coding tables are used to convert an input data word of p-bits to a code word of q-bits (q>p), and the code word string obtained by directly coupling the code words is recorded and reproduced in a recording medium such as an optical disk and magnetic disk, or transmitted via a transmitting portion, wherein the p-bits are 8 bits, the q-bits are 15 bits, and the predetermined run length restriction rule stipulates that a minimum run length of the signal obtained by NRZI-converting the code word excluding the synchronous signal is 3T, and a maximum run length is any one of 11T, 12T, 13T, and 14T.

Abstract: A table lookup extension instruction is provided in which index values stored within an index register D2 are used to select data elements stored within one or more table registers D0, D1 for storage into corresponding positions within a result register D3. Out-of-range index values result in the corresponding locations within the result register being left unchanged U. In this way, an offset can be applied to index values held and then those index values reused with the table registers D0, D1 being reloaded with a different portion of a table so as to give the effect of a larger table than can be directly supported by the number of table registers available.

Abstract: A method of decoding variable length codes converts a variable length code table into standard format decomposition tables from which a universal variable length decoder can decode. This allows the same universal variable length decoder to decode any variable length code. The memory required to store the standard format decomposition tables is minimized by the conversion process.

Abstract: This invention re-encodes encoded data (e.g., PackBits encoded data), which is expressed by a data format of a runlength code part indicating the runlength of the same data and a data part indicating the data, and a runlength code part indicating the runlength of a different data stream and a data part indicating the different data stream, to the same data format without decoding that encoded data, thereby improving a compression ratio. To this end, upon reception of data encoded by a PackBits encoding process, a data division unit separates that data into information indicating the runlength of data, and a data part, and outputs them as num and data. A data processing unit masks a predetermined bit in accordance with an instruction from a monitor unit, and outputs that result to a data combining unit. The data combining unit and a data output unit reconstruct and output data in the PackBits format in accordance with the masked data part and num data.

Abstract: Method and apparatus for use in Huffman decoding are described. In exemplary systems, a JPEG Huffman decoder is capable of simultaneously decoding multiple coefficients and/or symbols in a single table lookup. Methods for designing, building, and using such a table are included. Other embodiments are described and claimed.

Abstract: A demodulation apparatus and method using a code table that decreases complexity. The demodulation apparatus includes a code table including a plurality of the code words, wherein similar ones of the code words are arranged to be grouped together; and a soft demodulator to calculate probabilities of individual bits that constitute the code words, and to generate a soft demodulation value of the data word.

Abstract: The present invention correctly decodes data encoded with a variable-length encoding method that improves the compression ratio. The variable-length encoding method encodes a unit data composed of a plurality of sub-data while referencing a parameter table, and includes: an initialization step in which the parameter table is set to initial values; a parameter table information encoding step in which information related to the initialized parameter table is encoded; a parameter obtaining step in which encoding parameters to be used in the encoding of sub-data are obtained from the parameter table; a sub-data encoding step in which variable-length encoding of the sub-data is performed with reference to the obtained encoding parameters; and an encoded information placement step in which the encoded information is placed in a position in which the information can be obtained before the encoded unit data.

Abstract: A method and arrangement for arithmetic encoding/decoding is described, wherein the probability estimation is performed by a finite state machine FSM, wherein the generation of N representative states of the FSM is performed offline. Corresponding transition rules are filed in the form of tables. In addition, a pre-quantization of the interval width R to a number of K pre-defined quantization values is carried out. With suitable dimensioning of K and N, this allows the generation of a table containing all K×N combinations of pre-calculated product values R×PLPS for a multiplication-free determination of RLPS. Overall, the result is a good compromise between high coding efficiency and low calculation effort.

Abstract: An N-bit word is produced from an M-bit code received on an M-bit line, M being larger than N, the M-bit code comprising at least an M-bit code word and a previous M-bit code word, the M-bit code word comprising different levels at at least two bit positions, and the previous M-bit code word comprising levels opposite to the different levels at the corresponding bit positions, by comparing the levels at the two bit positions of the M-bit code word to obtain a first value, comparing the levels at the two corresponding bit positions of the previous M-bit code word to obtain a second value, detecting that the first value is opposite to the second value, and decoding the M-bit code word responsive to detecting that the first value is opposite to the second value. An advantage of the present invention is that all the lines taking part in the transmission have the same electrical characteristics, the same meaning and the same kind of loads.

Abstract: A mapper-based variable length coding method and decoding method and apparatuses therefor are provided. The mapper-based variable length coding method includes an inputting step for receiving symbol data to be coded and receiving element type information on the kind of symbol data, a coding step for generating a first code number corresponding to the received symbol data, a mapping step for selecting a second code number mapped with respect to selected element type information in mapping tables formed of second code numbers, each of which is appropriately mapped according to the first code number and the element type information, a codeword extracting step for generating a codeword corresponding to the selected second code number, and an outputting step for outputting the generated codeword. According to the methods and apparatuses, the advantages of a universal variable length code table can be maintained while preventing efficiency lowering of compression coding.

Abstract: Embodiments of the present invention mitigate crosstalk by equalizing transmit signals in a data dependent fashion.

Abstract: An apparatus and method for minimizing the code length of an input address for at least one for variable length encoded data is claimed. A block of variable length encoded data is read. The block of variable length encoded data is then converted into sub-optimall encoded data. The variable length encoded data is defined in having a prefix portion and a suffix portion. The prefix portion of the variable length encoded data is used to signify the look-up table. The suffix portion of the variable length encoded data is used as an input address for the look-up table.

Abstract: Methods and apparatuses for performing arithmetic encoding and/or decoding are disclosed. In one embodiment, the method for creating a state machine for probability estimation comprises assigning probabilities to states of a look up table (LUT), including setting a probability for each state i of the states equal to the highest probability of the LPS multiplied by the adaptation rate to the power i, where i is a number for a given state and the adaptation rate is smaller than 1. The method also comprises generating state transitions for states in the LUT to be transitioned to upon observing an MPS and an LPS, wherein the next state to which the state machine transitions from a current state when an MPS is observed is a next state higher than the current state if the current state is not the highest state and is the current state if the current state is the highest state.

Abstract: A method of decoding an encoded bitstream. The method includes performing a table lookup. Addresses into the table are generated using selected numbers of bits drawn from the bitstream in response to values stored in the table entries. A table entry may contain an index offset and a number of bits to extract from the bitstream. Alternatively, the table entry may contain the decode result. The value of a result tag in the entry signals which of the alternatives is contained in the entry. The table is recursively accessed until a portion of the bitstream is decoded. Any remaining portion of the bitstream is decoded similarly. An initial index into the table is determined from a number of bits of the bitstream corresponding to the length of the smallest code word in the codetable used to encode the bitstream.

Abstract: In a method of compressing a lookup table for reducing memory, a non-linear function generating apparatus having a lookup table compressed using the method, and a non-linear function generating method, X-coordinates of the non-linear function are separated into a plurality of sections including steps that have predetermined step sizes. Y-coordinate values corresponding to X-coordinate values are extracted for each step. The Y-coordinate values are stored in predetermined addresses in a memory, wherein the step sizes are different according to the sections. In this manner, memory capacity occupied by the lookup table is reduced.

Abstract: We present a method and apparatus for performing adaptive data compression. An alphabet and vocabulary in the encoder and decoder is built adaptively and stored in a dictionary as symbols are to be encoded and decoded. Each time an unknown symbol is to be encoded by the encoder, the encoder adds the symbol to the dictionary and transmits it in plain in the encoded string. The code words transmitted by the encoder include symbols and indexes. The state of a prefix bit preceding the code word indicates whether the code word is a plain symbol or an index of a symbol or string of symbols stored in the dictionary. The decoder examines the prefix bit of each code word as it is received to determine if the code word stores a symbol in plain or in index. If the code word stores a symbol in plain, the decoder learns the symbol by adding a sequence of symbols resulting from the concatenation of previously decoded symbols and the first symbol of the currently decoded symbol and by adding the symbol to its dictionary.

Abstract: The present invention provides a fast data converter for decoding compressed image data. This is accomplished by using a series of parallel and serial computational steps to decompress the compressed image data and reduce processing cycle time. The high speed decoder receives the input data stream including first and second parameters having initial values and which are representative of properties of the data stream, and a third parameter having a value which is representative of a decoding property of the decoder. The decoder then decodes the initial values of the first, second, and third parameters to determine updated values of the first and second parameters by using a combination of parallel and serial processing steps. The decoder then compares the determined value of the reference parameter with the computed first subtraction value and outputs updated values for the first and second parameters based on the outcome of the comparison by the comparator to reduce decoding cycle time.

Abstract: The present invention relates to a data processing apparatus. Additional information is embedded in coded data obtained by encoding image data, without increasing the amount of the coded data, and the data in which the additional information is embedded is correctly decoded into the image data and the additional information. An embedded compression encoder 11 encodes image data according to a predetermined coding rule, and destroys the coding rule based on additional information, thereby embedding the additional information. A decoder 12 restores the embedded coded data, obtained by embedding the additional information in the coded data, into the coded data encoded according to the coding rule, thereby decoding the additional information and also decoding the coded data into the image data.

Abstract: A limited value range is defined for obtaining approximated integer cosine transform coefficients. The transform coefficients of the base vectors for the submatrices are selected by taking into account the orthogonality condition so that the sum of their squares yields the square of the constant component coefficient. The coefficients of the variable components are derived from these coefficients. These measures yield the advantage that in quantization and normalization, a uniform normalization and quantization factor may be used for all coefficients.

Abstract: A method for decoding a bitstream of reversible variable length codewords parses the bitstream to extract a next reversible variable length codeword, transcodes each codeword into a pseudo-variable length codeword and decodes pseudo-variable length codeword. The transcoding produces at least some pseudo-variable length codewords suitable for leading zero lookup table decoding in specially adapted hardware. The transcoding may differ for reversible variable length codewords with initial “0” and initial “1”. These differing transcodings are decoded with may be decoded with a common lookup table or different sets of lookup tables.

Abstract: Methods and apparatuses for performing arithmetic encoding and/or decoding are disclosed. In one embodiment, a method for encoding data comprises coding a plurality of events in an event sequence to produce encoded data and generating a bitstream using the encoded data, including adding zero or more stuffing bits to the bitstream after the encoded data. The zero or more stuffing bits operate to substantially maintain a relationship between an amount of events encoded, a number of blocks being coded, and a number of bits in the bitstream.

Abstract: A method and structure stores and/or transmits and receives data in compressed form. Retrieval latencies are reduced by selectively transmitting a portion of the data in uncompressed form. When the apparatus is part of a computer architecture supporting main memory compression, a selected L2 cache line belonging to the unit of main memory compression is kept uncompressed. To minimize decompression latency, the uncompressed L2 cache line is stored with the compressed-memory directory. Alternatively, the uncompressed L2 cache line is stored in the compressed memory together with the rest of the memory compression unit it belongs to.

Abstract: A method of communicating a message between an automotive device of an automotive control area network and a non-automotive, industrial device of a non-automotive, fieldbus network includes receiving a message of a source format from one of the automotive device of the automotive control area network and the non-automotive, industrial device of the non-automotive, fieldbus network; translating the message of the source format to a common language format; processing the message of a common language format via a set of stored, configurable rules; translating the processed message of a common language format to a destination message format; and delivering the message in the appropriate destination format to one of the automotive device and the non-automotive, industrial device.

Abstract: Variable length decoding of DCT coefficients in MPEG video data is performed using a standard processor (400) and a small look-up table (LUT 530). The processor performs (520) an integer to floating point conversion on a portion the received bitstream (BS). By this step, lengthy codewords with many leading zeros, which are common in the codebook, are represented in a compressed form by the exponent and mantissa fields (EXP, MAN) of the floating point result (FP). The relevant bits are extracted and used as an index (IX) to address the LUT. This avoids cumbersome bit-oriented logic, while also avoiding a very large LUT that would otherwise be required to represent the same codebook. The entire LUT may thus reside in cache memory (410). In a VLIW processor implementation, decoding of one token is pipelined with the inverse scan and inverse quantisation step of the preceding token(s).

Abstract: A method and device for compressing data to allow for a simple and rapid evaluation of the compressed data.

Abstract: Signal conversion is implemented employing a memory system operating as a look-up table that stores a plurality of sets of output samples associated with each of a plurality of respective input samples. The look-up table thus can generate a corresponding set of output samples in response to a given input sample, thereby emulating desired digital upsampling and delta-sigma modulation. The output samples can be aggregated, such as by multiplexing, to provide an output data stream at a desired sample rate.

Abstract: An encoder and decoder provide coding of information communicated on busses. The encoder and decoder may use various combinations of techniques to reduce switching activity on an address bus.

Abstract: An apparatus and method for decoding a variable length code, wherein a user can set a variable length decoding table, are provided. The apparatus comprises a pre-decoding unit, a shifter, first through M-th look-up table address registers, selector, a memory controller, a memory, and a memory searcher. To decode a variable length coded data bitstream in units of 3 bits, a LOC information table can be prepared based on a variable length coding table. The LOC information table comprises LOC information bits and node types. LOC information bits for each node type are expressed using four formats A, B, C, and D to express the characteristic of a branch generated during 3-bit decoding, each of the formats A, B, C, and D having a digital value of 2 bits. The pre-decoding unit comprises a first pre-decoder and a second pre-decoder. One of the first pre-decoder and the second pre-decoder is selected according to the characteristic of a code of an input data bitstream.

Abstract: A method of lossless data compression is provided which uses a grammar transform to sequentially construct a sequence of greedy context-dependent grammars from which an original data sequence can be recovered incrementally. The data sequence is encoded using any one of a sequential context-dependent method, an improved sequential context-dependent method, and a hierarchical context-dependent method.

Abstract: A joint photographic expert group (JPEG) Huffman table decoder and a method thereof based on a binary search technique. The JPEG Huffman table decoder performs symbol matching based on the binary search and calculates an address of the matched symbol in code book data. Comparison time and an amount of memory required for searching the symbols are reduced.

Abstract: The present invention relates to a method for compressing a continuous data flow based on lossy compression. In real-time data compression, a series of data subsets acquired in a given period of time are treated as a regional data cube for the purpose of dividing a continuous series of data subsets into a plurality of data cubes. Reuse of existing codevectors is important in achieving high compression performance. For encoding spectral vectors on a subset-by-subset basis in a current region two types of codevectors are used, codevectors that have been newly trained for previous data subsets in the current region and codevectors trained for the previous region. The problem of a visible spatial boundary between two adjacent regions after decompression is overcome by reusing the codevectors trained from a previous region to encode the spectral vectors in the current region in order to attain a seamless conjunction of the two adjacent regions.

Abstract: An architecture for a turbo decoder performs a faster max* computation. In this architecture, one or more lookup tables begin processing a digital signal prior to the most significant bit of the digital signal stabilizes. This technique allows processing in the lookup table to be accomplished during a period of time in which processing could not be accomplished previously. As a result, the architecture performs the max* computations at a faster rate than previous architectures.

Abstract: Data modulating/demodulating method and system and apparatus using the same. The modulation method with smaller modulation table, compared to the conventional modulation table, is used to modulate the source data to the channel bits to be recorded to an external storage apparatus, such as optical disc. The demodulation method with smaller demodulation table, compared to the conventional demodulation table, is used to demodulate the bit data stream recorded on a storage apparatus, such as optical disc, to the original source data.

Abstract: Images are to be efficiently and easily encoded while suppressing block distortion and pseudo-contour generation. A quantization characteristics determining unit receives pixel values from a pixel value input unit, measures the length S of the consecutive occurrence of the same pixel values in connection with a pixel to be encoded and the pixel value differences D, and determines quantization characteristics n with reference to the result of sensory evaluation. A quantization/inverse quantization unit quantizes pixel values to be inputted with the quantization characteristics n, and further inverse quantizes them to reduce the number of gray-scale levels. The output pixel values of the quantization/inverse quantization unit are encoded and outputted by an entropy encoding unit.

Abstract: An apparatus and method for conversion of direct stream digital (DSD) signal samples to pulse code modulated (PCM) signal samples using a look-up table. The apparatus includes a first-in-first-out (FIFO) buffer that contains a plurality of bits from a DSD signal, the plurality of bits further divided into a plurality of words of the same size. The apparatus comprises a look-up table coupled to the FIFO buffer, the look-up table generating a result for each of the plurality of words. In one embodiment, the apparatus includes an accumulator coupled to the look-up table, the accumulator holding the results added together. After adding the result for the last word in the plurality of bits, the accumulator generates at an output a multiple bit PCM signal sample. The apparatus includes an address generator connected to the FIFO buffer and look-up table.

Abstract: Methods and apparatuses for variable length encoding using a vector processing unit. In one aspect of the invention, a method for execution by a microprocessor to perform variable length encoding includes: receiving a plurality of parameters, each of the plurality of parameters corresponding to one of a plurality of symbols to be variable length encoded; generating concurrently a plurality of first codewords from the plurality of parameters to represent respectively the plurality of symbols; generating a plurality of lengths representing respectively bit lengths of the plurality of first codewords; and outputting the plurality of first codewords and the plurality of lengths; where the above operations are performed in response to the microprocessor receiving a single instruction.

Abstract: An area of on-chip memory is allocated to store one or more tables of commonly-used opcodes. The normal opcode in the instruction is replaced with a shorter code identifying an index into the table. As a result, the instruction is compressed. For a VLIW architecture, in which an instruction includes multiple subinstructions (multiple opcodes), the instruction loading bandwidth is substantially reduced. Preferably, an opcode table is dynamically loaded. Different tasks are programmed with a respective table of opcodes to be stored in the opcode table. The respective table is loaded when task switching.

Abstract: An encoding efficiency higher than 1 is achieved by accomplishing ternary recording on a recording medium. For this purpose, an 8-bit binary data word is converted to a 5-symbol ternary code word. A look-up table stores a modulation/demodulation table defining the correspondence between the binary data word (8B) and the ternary code word (5T). A table generating circuit generates the modulation/demodulation table to be stored in the look-up table such that each of constraints specified by a plurality of parameters is satisfied. If a PRML (Partial Response Maximum Likelihood) scheme is combined with an 8B5T code thus obtained, a signal-to-noise ratio is improved.

Abstract: Computer-assisted methods for determining the state of charge of a specific lithium ion battery, without the need for charging and discharging the battery, by utilizing look-up tables or algorithms which store the relationships of state of charge to open-circuit voltage or to ramp-peak current, or to both for that type of specific lithium-ion battery to determine the state of charge for that specific lithium-ion battery.

Abstract: System and method for decoding variable-length codes. A variable-length decoder includes an address generator and a local memory unit. The local memory stores a variable-length code look-up table. The local memory can be programmed to include a look-up table supporting substantially any decoding algorithm. In one embodiment, a decoder memory unit and a system memory unit are employed together with the local memory to store a codeword look-up table. The shortest codes are stored in local memory, the next shortest in decoder memory, and the longest codes are stored in system memory. A multistage search algorithm is employed to search for the longest codes. The address generator generates the address of the code table to be searched by adding the value of the bits to be searched to a base address.

Abstract: A method of lossless data compression is provided which uses a grammar transform to sequentially construct a sequence of irreducible context-free grammars from which an original data sequence can be recovered incrementally. The data sequence is encoded using any one of a sequential encoding method, an improved sequential encoding method and a hierarchical encoding method.

Abstract: A computer implemented method and system for selecting a string for serving as a reference string for a comparison scheme for compressing a set of strings calculates preliminary compression results for every string relative to an initial reference string, and uses the preliminary compression results to find a better reference string without additional compression tests. According to one embodiment, a histogram is calculated showing the number of occurrences of each compressed length for each string in the set plotted against the initial reference string and the better reference string has a length corresponding to an average compression length or center of gravity of the histogram.

Abstract: A dictionary in which a character train serving as a processing unit upon compression has been registered is stored into a character train dictionary storing unit. In a character train comparing unit, the registration character train in the character train dictionary storing unit and a partial character train in non-compression data are compared, thereby detecting the coincident partial character train. A code output unit allocates a predetermined code every partial character train detected by the character train comparing unit and outputs. The character train dictionary storing unit allocates character train codes of a fixed length of 17 bits to about 130,000 words and substantially compresses a data amount to the half or less irrespective of an amount of document data.

Abstract: A method and apparatus for encoding or decoding data in accordance with an NB/(N+1)B block code, and a method for determining codebooks for use in such encoding or decoding. Some such methods select positive and negative codebooks that are complements of each other, including by eliminating all candidate code words having negative disparity and filtering the remaining candidate code words in automated fashion based on predetermined spectral properties to select a subset of the candidate code words as the code words of the positive codebook. Preferably, all but a small subset of the (N+1)-bit code words (determined by a primary mapping) can be decoded by simple logic circuitry, and the remaining code words (determined by a secondary mapping) can be decoded by other logic circuitry or table lookup.

Abstract: A method for correcting an error in N:N+1 channel codes categorizes 2N+1 codeword (N+1)-tuples into M subsets of codeword (N+1)-tuples, wherein each subset G has NG codeword (N+1)-tuples and the total number of codeword (N+1)-tuples in the M subsets is 2N and wherein each subset G has a predetermined number KG of lower bits and a predetermined number (N+1−KG) of higher bits and the number of lower bits in every codeword (N+1)-tuple in any subset is not equivalent to that of lower bits in every codeword (N+1)-tuple in any other subset. The 2N message N-tuples are mapped with said 2N codeword (N+1)-tuples in the M subsets, respectively, in one-to-one correspondence to generate a lookup table.

Abstract: An improved Huffman decoding method and an apparatus thereof are provided. The method includes (a) obtaining index information from a first bit of a codeword formed with bits of a part of a received encoded bit stream, and accessing an entry of the look-up table corresponding to the obtained index information, and (b) determining a type of the entry based on an internal value of the accessed entry.

Abstract: Mismatch-shaping for a digital-to-analog converter (DAC) involves allocating elements from an element array to multiple DAC channels. Various state variables are used to keep track of element usage, and the number of state variables is preferably less than the number of elements in the element array. The element array may be treated like a bi-directional circular array, in which case the array elements may be allocated to the two DAC channels as needed in opposite directions with reference to a common anchor point such that the array elements for each channel are contiguous within the circular array. All array elements are available for allocation to both DAC channels, although no array element can be allocated to both DAC channels simultaneously. A collision resolution scheme is used to prevent overlapping allocations of array elements. Pointers may be used to keep track of the array elements allocated to each channel, making implementation relatively simple.

Abstract: A decision feedback equalizer includes a lookup table device. The lookup table device may include a shift register and memory, or may include multiple shift registers and memories. Near-end crosstalk may be reduced using a lookup table device. Echo in a bi-directional port circuit may also be reduced using a lookup table device.

Abstract: The disclosed compressor utilizes a plurality of prefix tables corresponding to respective prefix codes. A string is stored by storing the code associated with the string in a prefix table corresponding to the code of the string prefix at a prefix table location corresponding to the extension character of the string. The input data character stream is searched by comparing the input stream to the stored strings to determine the longest match therewith. The code associated with the longest match is outputted so as to provide the output stream of compressed codes. The stored strings are updated by inserting an extended string into the prefix tables, the extended string comprising the longest match extended by the next data character in the input stream following the longest match, the extended string being stored in the prefix table corresponding to the code of the longest match, a code being assigned to the extended string.

Abstract: A method of decompressing data words of an instruction set includes: A. filling a primary dictionary with at least one primary data word of the instruction set, each of the at least one primary data word being stored in the primary dictionary in a location associated with a distinct primary dictionary index; B. filling at least one secondary dictionary with at least one difference bit stream, each of the at least one difference bit stream being stored in one of the at least one secondary dictionary in a location associated with a distinct secondary dictionary index; C. receiving a code word, the code word comprising: a. a header which identifies the primary dictionary and a specific one of the at least one secondary dictionary; b. a first bit stream; and c. a second bit stream; wherein the first bit stream comprises the distinct primary dictionary index and the second bit stream comprises the distinct secondary dictionary index; D.