Abstract: Methods and apparatuses for performing arithmetic encoding and/or decoding are disclosed. In one embodiment, an arithmetic decoder comprises a sequencer to generate a context identifier for an event of an event sequence, a probability estimator to determine a value for a LPS and a probability estimate for the LPS, and a decoding engine that includes a range register to assign a value to a range for the LPS. The value is based on the probability estimate, a value stored in the range register and the context identifier to a range for the LPS if the context identifier is not equal to an index and the value is not based on the value stored in range register if the context identifier is equal to the index. The decoding engine further determines a value of a binary event based on the value of the range for the LPS and bits from an information sequence.

Abstract: Method and apparatus for conducting a search to match a string of symbols of a sequence of symbols with a stored string of symbols in a dictionary to provide a matched string of symbols. In the method, after a matched string of symbols of the sequence of symbols has been found, beginning from a first position in the dictionary in which the first symbol of the matched string is stored, it is determined if a longer matched string of symbols can be found by first comparing a chosen symbol that follows the matched string of symbols in the sequence of symbols with a symbol stored in a corresponding position in the dictionary, beginning with another position in the dictionary in which the first symbol is stored, to determine whether the symbol stored in the corresponding position matches the chosen symbol. If the comparison does not result in a match, it is immediately known that a longer string of matched symbols has not been found and it maybe possible to omit additional comparing steps.

Abstract: A system and method that provides a unique or custom context for a plurality of blocks of data, yet compresses the blocks independently from the others, such that each block is independently decompressible. The method analyzes a collection of blocks for compression, and computes a unique context, such as a Huffman tree, given the distribution of symbols or phrases across all the blocks in the collection. Each block in the collection can be independently decompressed, in any order, using the shared context that is common to the collection.

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: A method, apparatus and computer program product for encoding data transmitted over a communications channel, including pre-loading an encoder dictionary with a set of character strings expected to appear in input data to be encoded; and encoding the input data with the set of expected character strings pre-loaded in the encoder dictionary. In another aspect, there is provided a method, apparatus and computer program product for decoding encoded data received over a communications channel, including pre-loading a decoder dictionary with a set of character strings expected to appear in the encoded data; and decoding the encoded data with the set of expected character strings pre-loaded in the decoder dictionary.

Abstract: An object of the present invention is to reduce bit depth and word number of a LUT memory 12 as small as possible, while obtaining &ggr; conversion output data with accuracy superior to the bit depth. Outputting table output data Dout0 and Dout1 which are associated with first table input data RA0 addressed and inputted to the LUT memory 12 and second table input data RA1 obtained by adding “1” thereto, and interpolating them outside the LUT memory 12, thereby obtaining output data having a larger bit depth than the LUT memory 12. At this time, the speed of signal processing is improved by employing a dual port memory as the LUT memory 12 or using a register group for the single port memory. Also, when the second table input data RA1 overflows, a specific value is employed as an alternative.

Abstract: There is provided an apparatus for storing/restoring holographic data and a method for coding/decoding holographic data. In a recording mode, the apparatus divides input data into a plurality of groups, each of which includes two binary digits; and encodes each of the groups into a 2×2 data block wherein a first row of the 2×2 data block has the two binary digits and a second row thereof has another binary digits generated by applying a binary differential calculation on the first row. In a restoring mode, the apparatus divides a signal restored from a storage media into a plurality of 2×2 data blocks; and decodes each of the 2×2 data blocks into two binary digits by comparing values of a first row of the 2×2 data block with those of a second row thereof. In this way, phenomena of isolated “on” or “off” can be avoided.

Abstract: A method of decompressing data words of an instruction set includes:

Abstract: The data compressor utilizes a plurality of subdictionaries arranged in levels for storing strings of data characters. The subdictionary at the first level stores two character strings and a subdictionary at a subsequent level stores strings that are one character longer than the strings stored in the subdictionary at the level prior thereto. A plurality of data characters are fetched from the input into an input buffer and applied to the respective levels. The subdictionary at a level is searched for the string comprising the string matched at the prior level extended by the fetched character applied to the level. The string code of a string matched at a level is cascaded to the next level. The longest match with the fetched characters is determined by one of the fetched characters resulting in a mismatch at one of the levels. The string code associated with the longest match is output.

Abstract: A data compressor includes a plurality of tandem coupled stages, each stage comprising a matrix of AND-gates and a matrix switch. An AND-gate has inputs responsive, respectively, to a representation of a prefix code and a representation of a character for energizing the AND-gate output. The AND-gate outputs are coupled, respectively, to the inputs of the matrix switch and the matrix switch outputs have respective string codes assigned thereto. The matrix switch is controllable for coupling any one of the matrix switch inputs to a selected one of the matrix switch outputs. Energization of an AND-gate output coupled to a matrix switch output provides a representation of the code assigned thereto. The provided representations of codes assigned to the AND-gates of a stage are coupled to the prefix code inputs of the AND-gates of the next following stage.

Abstract: An improved sliding window dictionary-based compression method limits the data within the sliding window searched to data strings occurring at each discrete match location within a plurality of predefined discrete match locations, the plurality of predefined discrete match locations comprising a set of non-continuous data positions within the window of data.

Abstract: For “Super Audio CD” (SACD) the DSD signals are losslessly coded, using framing, prediction and entropy coding. Besides the efficiently encoded signals, a large number of parameters, i.e. the side-information, has to be stored on the SACD too. The smaller the storage capacity that is required for the side-information, the better the overall coding gain is. Therefore coding techniques are applied to the side-information too so as to compress the amount of data of the side information.

Abstract: A data decompressor for decompressing an input stream of compressed codes to recover an output stream of data characters corresponding thereto. A plurality of character tables corresponding to respective characters store strings of data characters, the stored strings having respective string codes associated therewith. A string comprises a prefix string of at least one character followed by an extension character. A string is stored in the character tables by storing the code associated with the string prefix in the character table corresponding to the string extension character at a character table location corresponding to the string code of the string. The character tables are accessed with a currently received compressed code so as to recover a string corresponding thereto and the characters of the recovered string are output.

Abstract: A coding device and method in which m-bit information words are converted into n-bit code words such that the coding rate m/n is greater than ½. The coding device and method are also employed to record information on a recording medium and to transmit information. In the decoding method and apparatus, n-bit code words are decoded into m-bit information words. The decoding involves determining the state of a next n-bit code word, and based on the state determination, the current n-bit code word is converted into an m-bit information word. The decoding device and method are employed to reproduce information from a recording medium, and to receive information transmitted over a medium.

Abstract: A method, apparatus and computer program product for encoding data transmitted over a communications channel, including pre-loading an encoder dictionary with a set of character strings expected to appear in input data to be encoded; and encoding the input data with the set of expected character strings pre-loaded in the encoder dictionary. In another aspect, there is provided a method, apparatus and computer program product for decoding encoded data received over a communications channel, including pre-loading a decoder dictionary with a set of character strings expected to appear in the encoded data; and decoding the encoded data with the set of expected character strings pre-loaded in the decoder dictionary.

Abstract: A look-up table circuit includes address decoder circuitry that includes circuitry for utilizing the address decoder circuitry for producing secondary functions concurrently with operation of the address decoding operations. This eliminates or reduces additional circuitry required for generating the secondary functions.

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: A code generation unit generates an identification code inherent in a semiconductor substrate. A memory formed in another semiconductor substrate stores the identification code as a memory code. The identification code is written from the code generation unit to the memory before shipment of a semiconductor device as a product. A comparator circuit compares the identification code with the memory code and stops some operations of a predetermined circuit when the two codes do not coincide with each other. With this construction, a higher technical barrier (security) against fraudulent use of an appliance of the semiconductor device through replacement of the semiconductor substrate can be achieved.

Abstract: The data compressor utilizes a plurality of character tables arranged in levels for storing strings of data characters, the character tables corresponding to respective characters of the alphabet. A string is stored by storing the string code associated with the string in a character table corresponding to the extension character of the string in a location of the character table corresponding to the code of the string prefix. The character tables at the first level store 2-character strings and the character tables at a subsequent level store strings that are one character longer than the strings stored in the character tables at the level prior thereto.

Abstract: A look-up table scheme for performing non-return-to-zero inverted (NRZI) encoding on input data bytes. Also disclosed is a look-up table scheme for performing zero-insertion in data streams that so require. An address is formed from an input data byte and is then used to look-up the corresponding encoded/translated byte.

Abstract: An apparatus comprising a one or more memory circuits and an uncompress circuit. The one or more memory circuits may be configured to (a) store (i) a number of compressed code words and (ii) a number of delta words and (b) provide random access to the compressed code words in response to an address. The compressed code words may be losslessly compressed in response to (i) a number of uncompressed code words and (ii) the delta words. The delta words generally comprise bit strings that may be configured to minimize a size of the one or more memory circuits when deleted from the uncompressed code words. The uncompress circuit may be configured to losslessly uncompress the compressed code words in response to the delta words.

Abstract: An object of the present invention is to reduce bit depth and word number of a LUT memory 12 as small as possible, while obtaining &ggr; conversion output data with accuracy superior to the bit depth. Outputting table output data Dout0 and Dout1 which are associated with first table input data RA0 addressed and inputted to the LUT memory 12 and second table input data RA1 obtained by adding “1” thereto, and interpolating them outside the LUT memory 12, thereby obtaining output data having a larger bit depth than the LUT memory 12. At this time, the speed of signal processing is improved by employing a dual port memory as the LUT memory 12 or using a register group for the single port memory. Also, when the second table input data RA1 overflows, a specific value is employed as an alternative.

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: A data encoding device and a data decoding device. A data encoding device refers to first and second encoding tables to search for a code word correlated with encoding data. One of the code words is selected according to predetermined criteria. When the selected code word requires additional information, additional information is generated. A data decoding device refers to the first and second encoding tables and retrieves a data element from at least one of the tables. When additional information is available, original data is calculated based on the data element and the additional information. When additional information is not available, the retrieved data element is output without modification as original data.

Abstract: A retrievable memory is provided with a priority encoder. The priority encoder is constituted by encoder units. Each of the encoder units is constituted by an inverter, N-channel MOS transistors and an AND gate. Upon receipt of a signal of H level from a matching line, the encoder unit outputs a signal of H level to a word line, and also outputs a signal of L level to a matching line active signal line MLA1. Then, the encoder units respectively output signals of L level to the word lines. Consequently, even when a plurality of results of a retrieving process are obtained, it is possible to output single data.

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: A system and method for the dynamic power control of a ballast, wherein a compander is used to reduce dynamic input range requirements of an analog-to-digital converter (ADC) in power systems having dynamic signal ranges that are several orders of magnitude smaller than the largest signal being sampled. The present invention compresses an analog power signal and then digitizes and expands the signal to attain a digitized signal having an amplitude identical to the analog signal, thereby providing a power control system that is less expensive and less complicated than conventional power systems. The present invention can use algorithms to calculate both the expansion values and correction values required for a power control circuit to adjust an output power level toward a desired value.

Abstract: The data compressor utilizes a plurality of subdictionaries arranged in levels for storing strings of data characters. The subdictionary at the first level stores two character strings and a subdictionary at a subsequent level stores strings that are one character longer than the strings stored in the subdictionary at the level prior thereto. A plurality of data characters are fetched from the input into an input buffer and applied to the respective levels. The subdictionary at a level is searched for the string comprising the string matched at the prior level extended by the fetched character applied to the level. The string code of a string matched at a level is cascaded to the next level. The longest match with the fetched characters is determined by one of the fetched characters resulting in a mismatch at one of the levels. The string code associated with the longest match is output.

Abstract: In a data transmitter having a data encoder, an encoder mode is detected. Thereafter, an excluded codeword output by the encoder operating in the encoder mode is identified. Next, a selected bit in the excluded codeword caused to have a predetermined value to produce a non-excluded codeword. Finally, the excluded codeword is substituted with the non-excluded codeword, wherein the non-excluded codeword is selected to mitigate effects of a decoding error in a receiver associated with the excluded codeword.

Abstract: A method is disclosed for generating a PCM code set for encoding data by a PCM encoder in a data transmission system having a digital modem with a PCM encoder, a digital signal transmission path, an analogue signal transmission path with a central office line interface portion, and an analogue modem. The method includes the step of determining a minimum signal level distance between adjacent PCM codes of the PCM code set, the minimum signal level distance enabling discrimination by the analogue modem. Then a line interface attenuation of the central office line interface portion is determined. Finally, the PCM code set on the basis of a power limit computed by adding the line interface attenuation to a central office line interface power limit is generated. The invention further relates to an analogue modem to be operated in such a data transmission system.

Abstract: A program for decoding variable-length codes like Huffman codes is generated by receiving information describing a particular coding scheme that defines an association between source symbols and the variable-length codes, generating a binary tree that represents the coding scheme, generating a lookup table from the binary tree that can be used to decode variable-length codes having a length less than or equal to a threshold length, and processing the binary tree and the lookup table to generate the decode program.

Abstract: A multiple symbol length lookup table is described. The multiple symbol length lookup table includes a plurality of lookup entries and a plurality of lookup results, each lookup entry having a corresponding lookup result. Each lookup entry comprises a particular sequence of input data bits. The input data bits are encoded with a variable length coding. Moreover, the input data bits form one or more consecutive variable length symbols. Each lookup result comprises a total length of the consecutive variable length symbols in the input data bits. In an embodiment, the multiple symbol length lookup table is generated by using a single symbol length lookup table. In practice, the input data bits are submitted to the multiple symbol length lookup table as a lookup entry. In response, the multiple symbol length lookup table returns a lookup result that is the total length or number of bits in the input data bits that a variable length decoder can decode.

Abstract: A method of providing a backup of data of a memory portion, by at least one compressor and writer pair, to at least one storage medium having a plurality of segments is disclosed. The method includes partitioning the memory portion into a number of memory blocks. The compressor compresses data, block by block, to produce compressed data for each block. The writer writes the compressed data for each block to an associated segment of the storage medium. Compressing and writing are synchronized to occur in a pipelined manner so that the compressor is able to compress data of a next block without having to wait for the completion of writing of compressed data of an earlier block to the storage medium. A program storage device and a system for providing the above method are also disclosed.

Abstract: A symbol string detection unit detects the second symbol string matching the first symbol string having a predetermined length n from input character strings. A matching length detection unit detects a matching length k between the third symbol string following the first symbol string and the fourth symbol string following the second symbol string. A coding unit codes an input symbol string based on the symbol string detected by the symbol string detection unit and the matching length k detected by the matching length detection unit.

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: Frequency spectrums are determined for all possible codes given a predetermined number of bits in a code. A subset of these codes is formed based on spectral properties of codes in a desired frequency band. This subset of code is then used to encode data prior to transmission over a high-speed data bus to reduce undesirable emissions on targeted frequency bands.

Abstract: An angular position/position encoder is provided for determining the position of a moving part through evaluation of the direction-specific changes in the measured values recorded and for serial output in binary form of the position determined in this way, wherein all changes in measured values are also added together, independent of the direction of movement, and then output as the result of the total distance or angle traveled.

Abstract: The systems and methods relate to the compression of multiple files into a single file called an archive. Before appending the multiple files as one file to be compressed, the systems and methods arrange the order of files to increase the potential of redundancy among neighboring files, thus providing potential improvement in compression ratio and compression speed. In using a dictionary method to compress the multiple files appended as one file, a large dictionary is used in one embodiment to take advantage of potential between-file redundancies. In another embodiment, the redundancy characteristics of the multiple files are examined to dynamically determine the dictionary size. After the dictionary compression method produces an intermediary output data file, the intermediary output data may be separated into multiple sections, and a compression method that is potentially suitable for the data characteristics of each section may be applied.

Abstract: A multiple symbol length lookup table is described. The multiple symbol length lookup table includes a plurality of lookup entries and a plurality of lookup results, each lookup entry having a corresponding lookup result. Each lookup entry comprises a particular sequence of input data bits. The input data bits are encoded with a variable length coding. Moreover, the input data bits form one or more consecutive variable length symbols. Each lookup result comprises a total length of the consecutive variable length symbols in the input data bits. In an embodiment, the multiple symbol length lookup table is generated by using a single symbol length lookup table. In practice, the input data bits are submitted to the multiple symbol length lookup table as a lookup entry. In response, the multiple symbol length lookup table returns a lookup result that is the total length or number of bits in the input data bits that a variable length decoder can decode.

Abstract: Method and apparatus for conducting a search to match a string of symbols of a sequence of symbols with a stored string of symbols in a dictionary to provide a matched string of symbols. In the method, after a matched string of symbols of the sequence of symbols has been found, beginning from a first position in the dictionary in which the first symbol of the matched string is stored, it is determined if a longer matched string of symbols can be found by first comparing a chosen symbol that follows the matched string of symbols in the sequence of symbols with a symbol stored in a corresponding position in the dictionary, beginning with another position in the dictionary in which the first symbol is stored, to determine whether the symbol stored in the corresponding position matches the chosen symbol. If the comparison does not result in a match, it is immediately known that a longer string of matched symbols has not been found and it maybe possible to omit additional comparing steps.

Abstract: A method of decoding an encoded bitstream. The method includes performing a two-table lookup. A first table is addressed in response to a first plurality of bits from the bitstream. An address into a second table is generated using a value in an entry in said first table accessed in the addressing step. A value (representing the decoded value corresponding to the codeword in the bitstream) in an entry in said second table at the address from the generating step is output.

Abstract: A n-gram statistical analysis is employed to acquire frequently appearing character strings of n characters or more, and individual character strings having n characters or more are replaced by character translation codes of 1 byte each. The correlation between the original character strings having n characters and the character translation codes is registered in a character translation code table. Assume that a character string of three characters, i.e., a character string of three bytes, “sta,” is registered as 1-byte code “e5” and that a character string of four characters, i.e., a character string of four bytes, “tion,” is registered as 1-byte code “f1.” Then, the word “station,” which consists of a character string of seven characters, i.e., seven bytes, is represented by the 2-byte code “e5 f1,” so that this contributes to a compression of five bytes.

Abstract: A variable-length code decoder sequentially decodes a series of variable-length codewords included in a bit stream and outputs decoded symbols corresponding to the codewords. The decoder includes an interface section and a decoding section. The interface section accumulates various code lengths of the decoded codewords to obtain a sum. Next, the interface section selects an N-bit contiguous data sequence (where N is a maximum code length of the codewords) from a 2N- or (2N−1)-bit contiguous data sequence, included in the bit stream, in accordance with the sum and outputs the N-bit contiguous data sequence. The decoding section receives the output of the interface section and decodes a codeword included in a combination of the output and a previous output of the interface section by reference to a lookup table, thereby obtaining and outputting a decoded symbol and outputting a code length of the decoded codeword to the interface section.

Abstract: The present invention provides a data compression method in which a plurality of consecutive characters of a data string to be compressed are set as a character string to be searched for. Bits of a bit string representing the set character string are allocated to at least two codewords. Thus, first and second searching codewords are generated. These first and second codewords are used as array addresses. Fist and second array tables are prepared, in which information on the past occurrence positions of the set character string is previously entered as the contents thereof. When the first and second codewords are generated from the character string to be compressed, the first and second array tables are looked up by using these codewords as the addresses of the arrays. When results of looking up these tables match with each other, it is found that the set character string occurred in the past.

Abstract: A code word includes a first group of data bits and includes code bits that represent a second group of data bits. One embodiment of the code word has a minimum probability of bit transitions among its bits. Another embodiment of the code word includes a parity bit. Unlike conventional codes, a code that includes such a code word can have both a high efficiency and small error propagation. Additionally, by including fewer bit transitions, a sequence of such code words causes less read noise, and thus causes fewer read errors as compared to sequences of known code words. Moreover, the code word can include a parity bit to allow improved error detection as compared to known error-detection techniques. Therefore, such a code word can significantly increase the effective write and read speeds of a disk drive.

Abstract: A coding table portion includes six coding tables each storing a code word and status information indicating a coding table for use in modulating a next input data word in order to obtain a next code word which satisfies a predetermined run length restriction rule even if the next code word is coupled directly with the preceding code word, corresponding to each input data word. In the coding table portion, the code words and status informations allocated corresponding to input data words of a number set up preliminarily in succession from the highest appearance frequency to a lower one in one or more coding tables of the plural coding tables are replaced with code words having smaller RDSs and status informations allocated corresponding to other input data words in the same coding table. Consequently, the input data word is modulated using the six coding tables.

Abstract: There is provided a data storage device concurrently allowing storage of data that can be reproduced in higher quality and storage of data that can be used also in a data transmission path with a lower transfer speed. The data storage device comprises an A/D converter 103 for sampling analog audio signals based on a sampling frequency, a DSP 104 for compressing sample data sequentially output from the A/D converter 103, a storing and reading control unit 107 for storing the compressed data sequentially output from the DSP 104, and a control unit 105 for controlling the DSP 104 and the storing and reading control unit 107 for dividing the sample data sequentially output from the A/D converter 103 into a group under odd number of turns and a group under even number of turns, compressing the groups at each different compression rate and storing them on different storage areas A and B, respectively.

Abstract: A method of converting a stream of databits of a binary information signal into a stream of databits of a constrained binary channel signal, a device for encoding, a signal, a record carrier, a method for decoding, and a device for decoding. The signal is constructed by repetitively or alternately using channel codes C1 and C2. Since two channel words with opposite parities are available in the channel code C2 for each information word, and the same state is established, predetermined properties of the constrained binary channel signal can be influenced. Since the method further comprises the step of substituting, in dependence upon a value of a predetermined property of the binary channel signal, a channel word for a substitute channel word, wherein the substituted channel word and the substitute channel word establish the same state, predetermined properties of the constrained binary channel signal can be further influenced.

Abstract: A new method for compressing uniform entropy data, i.e. data streams of uniform probability distribution for binary code combination in the data stream, such files as MPEG, JPEG, ZIP, ARJ, etc. is disclosed. Contrary to the conventional compression algorithm which uses look-up table dictionary, the new lossless compression method eliminates the dictionary redundancy for temporal data stream and modulates incoming data stream by slicing unit module to have orthogonal correlation characteristics. According to the present invention, the method including the step of converting the uniform entropy property data stream at temporal period into non-uniform entropy property using correlation of continuous binary code combination and random occurrence thereof in the incoming data stream, thereby compressing the uniform entropy data in a lossless way.

Abstract: A decompressor recovers and outputs a stream of data characters corresponding to an input stream of compressed codes. The decompressor includes a dictionary that stores strings of data characters having respective codes associated therewith. A currently received compressed code accesses the dictionary to recover a string and the decompressor outputs the characters of the recovered string so as to provide the output stream of data characters. An extended string is inserted into the dictionary that comprises the string corresponding to the previously received code extended by the first character of the recovered string. A code is assigned to the stored extended string. The decompressor maintains counts of inserted extended strings that have the same extension character for respective characters of the alphabet.